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G D His Existence And His Nature -Rev. R. Garigou-Lagrange, O.P.


To grasp the profound meaning and the metaphysical import of the traditional proofs for the existence of God, we cannot do better than study them as set forth in the third article of the second question of Part I of the Summa Theologica of St. Thomas, where that learned philosopher and theologian reduces these proofs to their essential principles. See also Contra Gentes, Bk. I, cc. 13, 15, 16, 44; Bk. II, c. 15; Bk. III, c. 44; De Veritate, q. 5, a. 2; De Potentia, q. 3, a. 5; Compendium Theologiae, c. 3; Physica, Bk. VII, Lect. 2; Bk. VIII, Lect. 9 ff.; Metaphysica, Bk. XII, Lect. 5 ff.

Our purpose here is not historical, but merely to show that these proofs are closely connected with the first principles of reason, especially with the principle of non-contradiction or identity, and with the first of all human ideas, namely, that of being.

The two objections with which St. Thomas opens the above-mentioned article of the Summa Theologica are sufficient evidence that he was aware of the difficulties of the problem. They are the fundamental objections to which all others can easily be reduced. The first objection voices the opinion of the Pessimists; the second that of the Pantheists.

1. The first objection may be expressed briefly as follows: Evil exists; therefore an infinitely good God does not exist. For if He did exist, how could one account for all those defects, sufferings, and disorders in His work? This objection has been developed at great length by Schopenhauer. To say with Voltaire (Third Letter to Memmius), with John Stuart Mill (Essays on Religion, p. 163), with J. G. Schiller (cfr. Revue de Philosophie, 1906, p. 653), and with several contemporary authors, that it is a question of a finite God, very wise and very powerful, but not omnipotent, does not leave us so much as the nominal definition of God which determines the object itself of our proof.

For the development of this objection see Le Divin: Expériences et Hypothèses, by Marcel Hébert, Paris, 1907, pp. 148-164.


The solution of this difficulty belongs to the treatise on Providence (Ia, q. 22, a. 2, ad 2um), and we shall recur to it when we come to consider the harmonization of the divine attributes. For the present it is enough to indicate the answer of Catholic theology. St. Augustine has condensed it into a few words, which are quoted by St. Thomas: "If evil exists, it is not because God lacks power or goodness, but, on the contrary, He permits evil only because He is powerful enough and good enough to bring good out of evil ("Nullo modo sineret aliquid mali esse in operibus suis, nisi esset adeo omnipotens et bonus ut bene faceret etiam de malo." Enchiridion, ch. 2). In the presence of evil we see the triumph of the omnipotence and infinite goodness of God. He allows the death of the gazelle in order that the lion may live, and causes persecutions and the greatest of sufferings to redound to the glory of His martyrs. Not only does He enable souls to triumph over suffering, but He strengthens them by means of it, inspires them to become ever more serious of purpose and to attach themselves only to the things that are eternal. He purifies them by adversity and by the humiliations that He sends them. He protects them against pride or cures them of it. Moreover, physical evil is as nothing in comparison with moral evil or sin; and how could this latter make it impossible for Sovereign Goodness to exist, since sin presupposes it? In matter of fact, there is but one offence against God, which, like physical evil, He has permitted only in view of a greater good. It is our misery, which enables God to be merciful, just as creative power postulates absolute nothingness (Ia, q. 21, a. 3). The redemption, effected by the Incarnation of the Son of God, has made it possible for us to say "felix culpa." As for moral evil, which refuses to cooperate in what is good, it is compelled to do so by the chastisements which it calls down, by the manifestation both of Divine Justice and of the inalienable rights of Goodness, and it enables God to show Himself in all His majesty as the Judge (Ia, q. 25, a. 5, ad 3um). The small catechisms simply say: "There will be a general judgement, in order that all the good deeds and all the sins of men may be made known, and that all men may recognize the justice of God in rewarding the good and punishing the wicked." (See infra, no. 65, B).

Such is the Catholic answer to the problem of evil. In proving the existence of God, the theologian is well aware of the difficulties upon which the Pessimists insist; nay, he even foresees others. Far from stopping, as Voltaire did, at such disasters as the Lisbon earthquake, the theologian foresees that he will have to explain the rigors of Divine Justice by the very exigencies of the Sovereign Good. We shall return to this problem of evil in Part II, chs. 2, 3, and 4, of this book.

2. The second objection mentioned by St. Thomas is against the existence of God. It is said by the Pantheists that it is sufficient to admit two principles, nature and spirit; an eternal principle is not necessary, for: "Quod potest compleri per pauciora principia, non fit per plura." To claim, therefore, as Hébert does,

"La Dernière Idole," in Revue de Métaphysique et de Morale, July, 1902.


that St. Thomas did not know Pantheism, or chose to ignore it, is beside the question. It is certain that St. Thomas was aware of the two general types of Pantheism—that which reduces the multiple to one, becoming to being, and must end in denying the existence of the world (Acosmism), commonly attributed to Parmenides (Met., I, Lect. 9 of St. Thomas; Phys., Bk. I, Lect. 3, 4, 5 and 14); and that which, on the contrary, reduces everything to becoming, and inevitably results in a denial of the existence of God. This is atheistic Evolutionism, which is based upon Heraclitean principles (Met., Bk. I, Lect. 4). St. Thomas did not fail to see that Pantheism, in a certain sense, never existed, because it is absurd. Either the world is absorbed by God (Acosmism), or God is absorbed by the world and hence does not exist (Atheism). Against the Materialistic Pantheism of David of Dinant see Sent., II, dist. 17, q. 1, a. 1, and the Summa Theol., Ia, q. 3, a. 8: "Whether God enters into the composition of other things?" In the Ia, q. 76, a. 2 (see Cajetan's Commentary), and question 79, a. 5, as well as in the treatise entitled De Unitate Intellectus, we find the refutation of Averroism, which admitted but one intellect for all human beings.

The following proofs contain the solution of this Pantheistic objection.


34) The five main proofs. Their universality. Their order. What they are intended to demonstrate.


Before entering upon the classical proofs, it will be useful to determine the degree of their universality, to explain the order in which St. Thomas presents them, and to state precisely what each proof is intended to demonstrate.

These five arguments are typical and universal in range. All others can be reduced to them. They may truly be called metaphysical, for they are based on the highest metaphysical principles (ex summis metaphysicae fontibus sumuntur), in this sense that any created being whatever can be taken as the starting-point in the argument, ranging from stone to angel and ending in those five attributes which can be predicated only of that Being that subsists above all—Ipsum esse subsistens, subsistent Being itself, whence flow all the divine attributes. These five proofs are deduced from the laws of created being, viewed not inasmuch as they may happen to be of the sensible or of the spiritual order, but inasmuch as they are created. Every created being is mobile, caused, contingent, composite, imperfect, and relative. St. Thomas preferred to select his examples from the objects of sense perception, but he also applied these same proofs to purely spiritual things, to the soul and its intellectual and volitional movements. (See his answer to the second objection in the article just quoted; also Ia, q. 79, a. 4, and Ia IIae, q. 9, a. 4). Following the example of Aristotle, all treatises on general metaphysics or ontology, devoted to being as such, study the opposition between being moved and unmoved, conditioned and unconditioned, contingent and necessary; between being that is composite and imperfect and being that is simple and perfect; between relative and absolute being. St. Thomas here considers every created being (1) as subject to change; (2) as caused; (3) as contingent; (4) as composite and imperfect; (5) as multiplicity of design directed to some end. From these he concludes that there is a being which is (1) not moved; (2) not caused; (3) necessary; (4) simple and perfect; (5) directing all things to their proper end—which cannot be other than the Self-subsisting Being that is above all things, the "Ipsum esse subsistens" (Ia, q. 3, a. 4).

The general arrangement of these arguments, both with regard to their premises and their conclusions, must be carefully noted.

Since God is known by His works ("per ea quae facta sunt") St. Thomas first of all presents the most evident signs of contingency in the world; for that which did not exist, and suddenly comes into being, is obviously contingent. The most striking example is that of a body which passes from a state of repose to a state of movement. It is evident that such a body does not set itself in motion. From local movement we may pass on to qualitative movement (gradual intensification of a quality such as heat and light), to accelerated movement, in fact, to all kinds of becoming, even that form of it which is found in the intellect and the will and which exists in every finite mind. A thought, a volition arises in consciousness which was previously non-existent. Clearly it does not come into existence by itself, nor does the soul possess it by its own power.

It has been asserted that this first proof given by St. Thomas applies only to movements of the physical order, especially to local movement.

See Chossat in the Dict. de Théologie Cath., art. "Dieu," cols. 931-934.


As a matter of fact, local motion is merely given as the most striking example of movement in the sensible order. To be convinced of this, one has only to read the article in the Summa Theologica entitled: "Whether God works in every agent?" in which St. Thomas presents this argument from motion, referring to God as the first cause. He writes: "The first agent moves the second to act. And thus all agents act by virtue of God Himself. . . . God moves things by applying, as it were, their forms and powers to operation." (Ia, q. 105, a. 5). In three other passages, to which we have had occasion to refer previously, (Ia, q. 2, a. 3, ad 2um; Ia, q. 79, a. 4; Ia, IIae, q. 9, a. 4), the proof from motion is expressly applied to movements of the intellect and the will.

This first argument is designed to establish the fact of a source of becoming, of a first mover who is immovable, in this sense that he possesses within Himself the source of His own activity and has no need of being moved by another. Thence may be deduced: the pure actuality of the first mover (Ia, q. 3, a. 1 and 2); His aseity (ibid., a. 4) ; His absolute immutability. (Ia, q. 9, a. 1 and 2); His eternity (Ia, q. 10, a. 2), etc.

St. Thomas could have established by an a priori proof that the first mover must be the first efficient cause, the source, not only of becoming, but also of being. He preferred to give an a posteriori proof of this, and the second proof is based, not upon the dependence of becoming on the force which previously set it in motion, but on that of being (which is the permanently abiding terminus of becoming) with respect to efficient causes which not only produce it, but conserve it in being. If we wish to grasp the full force of this argument, we must read the two articles in which St. Thomas discusses this question from the opposite point of view. In the first of these (Ia, q. 104, a. 1), "Whether creatures need to be kept in being by God?" he distinguishes clearly between being and becoming, between fieri and esse. The second article is entitled, "Whether God preserves every creature immediately?" and arrives at the conclusion that there is a first cause, the source of being, which is not itself the effect of any cause, nor preserved in its being by any higher cause. From this follow the Prime Mover's aseity (Ia, q. 3, a. 4), creative omnipotence (Ia, q. 25, a. 3; q. 44, a. 1 and 2; q. 45, a. 2 and 5), immensity and ubiquity (Ia, q. 8, a. 2), etc.

St. Thomas could have proved a priori that the first mover and the first cause must be the necessary being. But he proved a posteriori the existence of a necessary being by a third argument, which starts out, not from the dependence of becoming or being on their respective causes, but from the possibility of the nonexistence of a being which is caused; in other words, its contingency. Thus this proof is more general than the preceding ones, for it can be applied not only to becoming, not only to being which did not previously exist, but to everything which has not its sufficient cause in itself. St. Thomas particularly insists on the evidence of the senses attesting to the contingency of material things; but his point of departure is more universal, namely, the basic proposition that what can just as well not be, must have for its cause a necessary being ("quod possibile est non esse pendet a necessario"). This third proof, universal in its scope, concludes merely to the existence of a necessary being, which exists of and by itself (a se). From this fact (aseitas) we argue that such a being is self-subsistent, or Being itself (Ia, q. 3, a. 4), whence all the absolute perfections can be deduced.

The fourth way seeks for a sign of contingency in the ultimate profundities of created being. Here we find ourselves placed in the static order, confronted with beings which we do not necessarily need to have seen coming into existence or ceasing to exist. To detect their contingency, we have recourse to something which, on first consideration, appears not so convincing, but is more profound and more universal than movement, generation or corruption, namely, multiplicity, composition, and imperfection. The multiple, the composite, the imperfect—all demand a cause just as well as becoming does; and this cause must be not only uncaused, but unique, absolutely simple, and absolutely perfect. From this we conclude that God is not corporeal (Ia, q. 3, a. 1), that He is not composed of essence and existence, but that He is the self-subsistent Being at the head of creation (Ia, q. 3, a. 4); that He is not included in any genus (Ia, q. 3, a. 5); that He is sovereign goodness (q. 6, a. 2) ; that He is infinite (q. 7, a. 1); that He is the sovereign truth (q. 16, a. 5); that He is invisible and incomprehensible (Ia, q. 12, a. 4 and 8). The proof based on the eternal verities which concludes the existence of a Supreme Truth, as well as those derived from the notions of absolute goodness and of the compelling force of what is upright and good, enable us to conclude to the existence of that Supreme Good, which is the source of all happiness and the foundation of all becoming, are but variations of the fourth way.

The fifth proof emphasizes the preceding fourth. It is based upon the notion of multiplicity—not of any sort of multiplicity, but of that which gives evidence of design. In other words, the argument derives its force from the idea of the orderly arrangement of things in the world. It establishes as its conclusion, not a unity of some kind or other, but a unity of conception, which means that there is an intelligent designer. This argument applies to every being in which there is a trace of design: whether it be a case of essence designed for existence, or of intelligence ordained to its proper act (potentia dicitur ad actum). Since the existence of a first cause has already been proved, the fifth proof reveals this cause to us as a Supreme Intelligence. From this intelligence, considered as an attribute of the self-subsisting Being (Ia, q. 14, a. 1), we conclude to the Wisdom and Foreknowledge (Ia, q. 14), the Will (q. 19), and the Providence (Ia, q. 22) of that same Being. This last and more popular proof, which seems to be simpler than the preceding one, in reality presupposes it, and of all the proofs for the existence of God is perhaps the one which, considered strictly on metaphysical grounds, presents the greatest difficulty in being referred back to the first principles of reason, on account of its complexity. It is probably on this account that St. Thomas put it in the last place.

Briefly, then, and in a general way, we may say that the contingent (that which, by its definition, may either exist or not exist), demands a necessary being (third proof); that movement, which is the simplest example of contingency, demands an unmoved mover (first proof); that conditioned being demands an unconditioned being (second proof); that the multiple presupposes the one, the composite the simple, and the simple and imperfect presuppose the perfect (fourth proof); that a multiplicity of design postulates an intelligent designer (fifth proof). Now the necessary being, the first mover, the first cause, which is absolutely one, simple, perfect, and intelligent, is that being which corresponds to the idea that comes to the mind when one utters the word God (nominal definition). Therefore, God exists.

From any one of these five divine attributes we may establish the reality of that Being whose essence is identical with His existence, and who for this reason is Being Itself (Ia, q. 3, a. 4). The proof for God's existence is thereby firmly established. The nature of God is all that remains for us to study, and Self-Subsisting Being becomes the principle from which we can deduce the divine attributes. Thus we shall see, as Fr. del Prado, O.P., shows in his treatise De Veritate Fundamentali Philosophiae Christianae,

Fribourg in Switzerland, 1911.


that the supreme truth, not in the analytical order or the order of invention,

See Ia, q. 79, a.9. "For by way of finding, we come through knowledge of temporal things to that of things eternal; but by way of judgment, from eternal things already known we judge of temporal things."


but in the synthetic or deductive order, that truth which is the final answer to our questions concerning God and the world, is the identity of essence and existence to be found in God alone. "In solo Deo essentia et esse sunt idem," whence the definition of God expressed in His own words: "I am He who is."

This will be the last word in reply to such ultimate metaphysical questions as: Why is there but one being who is uncreated, immutable, infinite, absolutely perfect, sovereignly good, omniscient, free to create, etc.? Why did all the other beings have to receive from Him all that they are, and why must they expect from Him all that they desire and may become? The treatise on God thus rests fundamentally on the proposition that "In solo Deo essentia et esse sunt idem: in God alone are essence and existence identical." This same proposition is the terminus in the inductive order of metaphysical reasoning, by which we conclude to God's existence, and it is also the principle from which, by the method of deduction, we arrive at the same conclusion.


35) General proof, which includes all the others. Its principle is that the greater cannot proceed from the less. The higher alone explains the lower.


Before examining each of these five typical proofs in detail, we shall give a general proof which includes all the others, and which, we believe, most aptly illustrates what is commonly accepted as the essential point in establishing the existence of God. The principle of this general proof, i.e., that "The greater cannot proceed from the less," condenses into one formula the principles upon which our five typical proofs are based. These principles may be stated as follows: "Becoming depends upon being which is determined;" "Conditioned being depends upon unconditioned being;" "Contingent being depends upon necessary being;" "Imperfect, composite, multiple being depends upon that which is perfect, simple, and one;" "Order in the universe depends upon an intelligent designer." The principles of the first three proofs especially emphasize the fact that the world depends for its existence upon a cause, while the last two principles stress the superiority and perfection of this cause. These may then all be summed up in the formula that "The greater cannot proceed from the less; only the higher grade of being explains the lower."

This general proof will have to be scientifically established by the five other proofs. Though it is in itself somewhat vague, it becomes strong and convincing when united with the others. We have here a concrete case of what the theologians teach about the natural knowledge of God. "Although the existence of God needs to be demonstrated," writes Scheeben (Dogmatik, II, n. 29), "it does not follow that its certainty is merely the result of a scientific proof, one of conscious reflection, based on our own research or on the teaching of others; nor does it follow that this certainty is due to the scientific accuracy of the proof. On the contrary, the proof required so that anyone may arrive at complete certainty is so easy and so clear that one scarcely perceives the logical process which it involves, and that the scientifically developed proofs, far from being the means by which man first acquires certainty of the existence of God, merely clarify and confirm the knowledge which he already has. Moreover, since the proof, in its original form, presents itself more or less as an ocular demonstration, and finds an echo in the most hidden recesses of the rational nature of man, it establishes a conviction on this basis which is firmer and less open to attack than any other, no matter how ingeniously contrived, and cannot be assailed by any scientific objection." Thus are verified the words of Scripture when it chides the pagans, not for having neglected the studies necessary for acquiring a knowledge of God, but for having violently suppressed the divine truth clearly made known to the mind of man. (Rom. I, 18; II, 14). To deny the existence of God is an insult to nature (μάταιοι ϕύσει; Wisd. XIII, 1) as well as to reason ("Dixit insipiens in corde suo: non est Deus; Ps. XIII).

This general proof may be stated as follows, by ascending from the lower beings up to man:

We know from experience that there are beings and events belonging to different orders. Certain things in nature are inanimate (minerals); and there is the vegetative life (in plants), the sensitive life (in animals), and the intellectual and moral life (in man). All these things come into existence and disappear again, they are born and they die, which shows that their activity has a beginning and an end. Evidently they do not exist of and by themselves. What, then, causes them to come into being?

If there are things in existence at present, there must have been some thing in existence always. "If at any particular moment of time nothing exists, then nothing will ever come into existence." "Ex nihilo nihil fit." The principle of causality tells us that nothing cannot be the reason or cause of actual being. To say that the series of perishable things had or did not have a beginning, does not solve the problem. If the series is eternal, it remains eternally insufficient; for the perishable beings of the past were just as indigent as those now existing, and not in any sense self-sufficient. How could any one of them, not being able to account for its own existence, account for those that follow? This would be the same as admitting that the greater proceeds from the less. We must admit, therefore, that above perishable beings there is a First Being, who owes existence only to Himself and can give it to others. (General Proof based on the fact of contingency; see n. 38).

If living beings exist to-day, and if life is superior to brute matter, it could not have evolved from the latter, for to assert this would mean that the greater comes from the less, or, what amounts to the same, that being comes from nothing. Just as being, as such, cannot come from nothing, living being cannot proceed from that which is non-living and of a lower order than life. The First Being must, therefore, have life (n. 49). This necessary conclusion becomes practically evident to the senses if we suppose that it is an established fact of positive science that the series of living beings had a beginning.

If there is such a thing in the world to-day as intelligence and knowledge; if intelligence is superior to brute matter, to the vegetative and the sensitive life; if the most domesticated of animals can never be trained so as to grasp the principle of sufficient reason or the first principle of the moral law: intelligence could never have evolved from these lower grades of being, but it is necessary to admit an intelligent being existing from all eternity. The intellectuality of this being cannot be, like ours, contingent; for, not being responsible for its own existence, how could it account for that of others? This means that the First Being is of necessity intelligent. If everything originated from matter, from a lump of clay, how could human reason, or the mind of man, have evolved? "There is no greater absurdity than to admit that intelligent beings are the result of a blind and material fatalism," says Montesquieu (proof based on the contingency of mind; see infra, n. 39, b). And how could there be order in the world without an intelligent designer? (proof from the evidence of order in the world; infra n. 40).

If the series of rational principles, which dominate our reason and all reality, actual as well as possible, are necessary, and consequently superior and anterior to all contingent intellects and realities which they regulate, then they are independent of the latter, and there must always have been some intelligent being reigning supreme in the realm of the possible, the real, and the intellectual. This supreme intellect must have been in possession of a first and unchangeable truth. In other words, if the intelligible and its necessary laws are superior to the unintelligible and the contingent, they must have existed from all eternity, for they could not possibly have originated from that which in no wise contained them (proof based on the eternal truths; infra n. 39, c).

If, finally, there are in the world to-day, morality, justice, charity, if we can attribute sanctity to Christ and Christianity, if this morality and this sanctity are of a higher order than what is neither holy nor moral, there must have been from all eternity a moral, just, good, and holy Being. The soul of a St. Augustine or a St. Vincent de Paul, the humblest of Christians for whom the words of the Pater Noster have a message to convey—is there anything more absurd than to say that these are the result of a material and blind fatality? Can the desire for God and for perfect holiness be explained apart from God? Can the relative be explained apart from the absolute? (Proof based on the contingency of mind, applied to morality and religion in practice).

If the first principle of the moral law, namely, that we must do good and avoid evil ("Do your duty, let happen what may,") forces itself upon us with no less objectivity and necessity than the principles of speculative reason; if the really good, which is the object of our will (good in itself, superior to useful and delectable good), has a right to be loved and willed apart from the satisfaction and the advantages to be derived from it; if the being capable of such an act of the will must so will, in order to retain its raison d’être; if the voice of conscience proclaims this right of the good to be loved, and afterwards approves or condemns, without our being able to stifle the feelings of remorse; if, in a word, the right of good to be loved and practised dominates our moral activity and that of societies, actual and possible, just as the principle of identity dominates the real, both actual and possible, then there must have been from all eternity a foundation for these absolute rights. These necessary and dominant rights cannot be explained and regulated by any contingent reality. Since they are above everything except the Absolute Good, it is only the latter that can explain their existence. (Proof based on the moral law; n. 39, c). If we are conscious of a moral law within us which is superior to all human legislation, there must be a supreme legislator.

Therefore, there must be a First Being, who is at the same time Life, Intelligence, supreme Truth, absolute Justice, perfect Holiness, and sovereign Goodness. This conclusion is based on the principle that "the greater cannot proceed from the less," which in turn is merely a formulation of the principle of causality, already discussed. "Quod est non a se, est ab alio quod est a se": That which has not its reason for existing in itself, must derive that reason from another being, which exists by and for itself (see supra, no. 9). The lower grades of being (lifeless matter, the vegetative and sensitive life), far from being able to explain the higher (intelligence), can be explained only by this latter. The simplest of material elements, such as the atom and the crystal, far from being the principle of things, can be explained only by an idea of type or final end. The display in them of intelligent design can have been caused only by an intelligent designer. The physical sciences, if they have any objective validity, reveal this intelligible law or sufficient reason, but are not the cause of it. (Proof based on the notion of final causes; n. 40).

This general proof shows us the absurdity of Materialistic Evolutionism, based on an antiscientific and antiphilosophical hypothesis. It is antiscientific, because it presupposes the homogeneity of all phenomena, from the physical-chemical up to the most sublime acts of philosophical and religious contemplation. Now, science has nothing to adduce in favor of such a homogeneity; on the contrary, as Dubois-Reymond remarks in his work, Les Limites de la Science, science is confronted with seven baffling problems, namely, (1) the nature of matter and of force; (2) the origin of movement; (3) the first appearance of life; (4) the apparent finality of nature; (5) the appearance of sensation and consciousness; (6) the origin of reason and language; (7) free will. This is tantamount to saying that science cannot explain the higher forms of reality by the laws of inanimate matter. Materialistic Evolutionism is also antiphilosophical. Whatever the degree of fecundity and however numerous the qualities which may be ascribed to it, it is always, by its very definition, blind necessity or a blind contingency (absence of intelligence). How could a superior intelligence ever have evolved from it? The physical and chemical laws cannot explain intelligence, but receive their own explanation from it alone.

This general proof also furnishes a virtual refutation of Idealistic Pantheism. The required First Being, who is entirely independent of everything not itself, is also endowed with intellect and will—and these three notes constitute personality. Moreover, we cannot think of ourselves as modes or accidents of this Being, for if the greater cannot proceed from the less, the principle of things must from all eternity possess the plenitude of being, intelligence, truth, and goodness. It is not susceptible of further perfection, nor can becoming be attributed to it, since becoming in its final analysis presupposes privation. (See nos. 36, a and 39, a.).

Some Evolutionists (e. g., John Stuart Mill; supra n. 12), make bold to affirm that the greater does proceed from the less, being from nothingness, mind from matter. Hegel sees no difficulty in admitting the same conclusion, since for him the principle of contradiction has no objective significance, and being and non-being are identical.

Many Positivists (Haeckel, for instance) are inclined to accept the principle that the greater cannot proceed from the less, but deny the superiority of life, sensation, and thought, which they regard as merely the result of physical forces in harmonious combination. Primitive matter, they say, is not only ponderable, inert, and passive, but also ether, which is imponderable matter perpetually in motion. The atom which is attracted by another atom is an example of sensation and inclination in the rudimentary stage; in other words, it is a soul in embryo. The same must be said of molecules, which are composed of two or more atoms, as well as of the far more complex compounds of these molecules. The way in which they combine is purely mechanical; but by reason of this very mechanism the psychic element of things becomes complicated and diversified in accordance with their material elements.

See Haeckel, The Riddles of the Universe, ch. XII, and the criticism of this system by E. Boutroux, Science et Religion, p. 139.


From this point of view, philosophical or religious contemplation is not essentially of a higher order than the functions of the liver or the kidneys. These Materialistic Positivists are forced to conclude that the harmony prevailing in the laws of nature cannot be ascribed to an intelligent cause, but is the result of chance or blind necessity. In defence of their thesis they appeal to the principles of modern physics, especially to the principle of the conservation of energy, which is commonly interpreted as meaning that "nothing is lost and nothing is created." If nothing is lost and nothing is created, then a living, rational being can, strictly speaking, only expend and restore the motive energies received from outside, not only without any quantitative additions, but even without modifying the natural tendencies of these energies by their own spontaneous action; for to change the direction of a force requires force, and we cannot create force. The sum-total of available energy in the universe is fixed, either from all eternity or since the coming into being of things. The intellectual and moral life is but a reflex of the physical life.

In his thesis on La Contingence des Lois de la Nature (1874), E. Boutroux replied to this objection by pointing out that the conservation of energy cannot be advanced as a primordial and universal necessity which would explain everything else, since it is itself but a contingent and partial law in need of a cause. "The most elementary and the most general of the physical and chemical laws of nature," he says, "declare what relationships exist between things so heterogeneous that it is impossible to say that the consequent is proportionate to the antecedent and results from it, as the effect from its cause. . . . For us they are merely a series of connected events which we have experienced, and no less contingent than experience itself. . . . The quantity of physical action may increase or decrease in the universe or in parts of the universe." (3rd ed., p. 74). This law of the conservation of energy is not a necessary truth, a supreme law which nature is compelled to obey; itself contingent, it demands a cause. Even if it were a necessary law, like the principle of contradiction, it would not explain the existence of nature, the existence of beings in which it is found, and which may be conceived as not existing. Furthermore, it is but a partial law; man finds it operative in a special sphere, that of physics and chemistry, and even in this inorganic sphere its verification is but approximate. "How can it be proved that the phenomena observed in physics are not in any way deflected from their own natural course by some superior intervention?"

Boutroux, ibid., p. 85.


The law is true only of a closed system, removed from all external activities, in which the sum-total of potential and actual energy remains constant; but how can it be proved that the physical universe is a closed system?

See in the Revue Thomiste (Jan., 1905) an article written by the Rev. R. Hedde on "The Two Principles of Thermodynamics." We quote from it the following lines: "The law [of the conservation of energy] is applicable only on the supposition that the universe is a system closed to all external action; this hypothesis, necessary for the establishment of the law, cannot be the corollary of this law. If, therefore, spiritual substances intervene in the world of material things, the demonstration of the law will be defective; for we shall be unable to foresee, as far as physics is concerned, the consequences of such an intervention. It seems that certain spiritual philosophers have been entirely wrong in holding that the principle of the conservation of energy constitutes an objection against human freedom. Even if human freedom were able to modify the quantity of total energy in the universe, the physicist would still have the right to proclaim the principle of the conservation of energy, the only one in which he is interested; for what concerns him is not to maintain the constancy of a sum about which he knows nothing, but to know that the phenomena which he studies cannot possibly bring about a variation of the said principle. Therefore, the law no more affects human than it affects divine freedom; the objection is valueless against both forms of freedom." (Revue Thomiste, Vol. XII, p. 726. See also Cursus Philosophiae Thomisticae, by P. Hugon, O.P., Vol. IV, p. 172; de Munnynck, O.P., "La Conservation de l'Energie et la Liberté Morale in Revue Thomiste, 1897, pp. 115 ff.; and Sept., 1899, and also Science et Religion, a series of pamphlets. Also Fr. Couailhac, S.J., La Liberté et la Conservation de l'Energie).


In the biological field the verification of this law is an impossibility, "for we cannot pass judgment on an infinitely large number of infinitely small forms of life."

Rabier, Psychologie. p. 543.


As for the extension of this law to the domain of the spirit, the hypothesis is not only incapable of verification, but absolutely gratuitous. "Not only is it unnecessary that the world of the spirit should be governed by the same laws which regulate the world of bodies, but since the spiritual is of a different nature from the corporeal, it would be most extraordinary if it did not have its own laws."

Mgr. d'Hulst, Confér. de Notre-Dame, 1891, p. 396.


Boutroux in his thesis on the Contingency of the Laws of Nature

We shall see later on (n. 40) that the laws of nature are hypothetically necessary. This thesis of Aristotle avoids the excesses of absolute Determinism and those of Contingentism, which merely rejects necessity in order to rely upon chance or undisciplined freedom. See the end of this work for a discussion of the relations between free will and the absolutely necessary principles of reason and being (n. 61).


has also established the fact that there is no inherent necessity with regard to the physical and chemical forces of nature, in virtue of which they are bound to produce that combination which results in life, sensation, and intelligence. The actualization of these higher forms of life is contingent, and hence demands a cause different from that demanded by the physical and chemical laws. The universe presents itself to us as a hierarchy of natures, of which the higher forms cannot be conceived as a mere production or development of the lower. Thus the traditionally accepted general proof is confirmed, and has lost nothing of its validity.

We shall now explain more fully and defend scientifically, i.e., with metaphysical arguments, this general proof by means of the five typical proofs as formulated by St. Thomas.


36) Proof from motion. A. The proof.—B. Objections.—C. Consequences.


A. The proof. We shall first present this proof in its widest sense (a) by starting from the notion of motion; then we shall apply it to (b) physical motion, and afterwards to (c) spiritual motion. (Concerning this proof, see Aristotle, Physics, Bk. VII, Comment. of St. Thomas, Lect. 1 and 2; Bk. VIII, Lect. 9, 12, 13, 23; John of St. Thomas, Cursus Philosophicus; Philosophia Naturalis, q. 24, a. 3, and Cursus Theologicus, In Iam, q. 2, a. 3).

a). Taken in its widest sense, this proof claims to establish the existence of a being immovable from every point of view, and, therefore, uncreated; for in the case of every created being there is at least the transition from non-being to being, which conflicts with the notion of absolute immutability.

The existence of motion or change is the starting-point of the argument, without stating precisely whether the change is substantial or accidental, whether the motion is spiritual or sensible, local, qualitative or by way of augmentation. When arguing against Pantheism it is not at all necessary to assume a plurality of distinct substances, but it suffices to admit the existence of any kind of motion and to study it as motion. Internal and external experience confirms the existence of motion. Zeno declared motion to be impossible, but this declaration was based on the gratuitous and false hypothesis that the continuous is composed of indivisible parts.

See Aristotle, Physics, Bk. VI; on Aristotle's refutation of Zeno, cfr. Baudin, "L'Acte et la Puissance," in Revue Thomiste, 1899, pp. 287-293.


Starting from motion, we gradually arrive at the conclusion that there is an absolutely immovable being, and this by means of two principles: (1) Whatever is in motion, is set in motion by another; (2) in a series of actually and essentially subordinate movers, there is no regress to infinity. Hence we must finally arrive at a first mover which itself is not moved by any kind of motion.

The first proposition, "Whatever is in motion, is set in motion by another," is based on the nature of motion or becoming. As we have already shown (see nos. 21 and 26), becoming presupposes the absence of identity; it is a successive union of diverse things (for instance: that which is here, afterwards is there; that which is white becomes grey; the intellect from a state of ignorance gradually acquires a knowledge of things, becomes more penetrating, etc). This successive union of diverse things cannot be unconditioned; to deny this proposition would be to deny the principle of identity and to say that diverse elements, which of themselves do not follow one another, do of themselves follow one another; it would mean to say that ignorance, which of itself is not knowledge, nor in any way connected with knowledge, nor the result of knowledge, can of itself be the result of knowledge. To say that becoming is its own sufficient reason, is to make contradiction the principle of all things (see n. 21).

If we study this becoming more closely, we observe not only that it is not unconditioned, but also that it requires a determinate cause, i.e., one that is in act. In fact, if we consider that which becomes, we are obliged to say that it is not yet what it will be (ex ente non fit ens, quia jam est ens), and that it is not the absolute nothing of that which will be (ex nihilo nihil fit); at least, there must be a possibility of its being what it will be; for instance, that only can be moved locally which is susceptible of being moved; that only which is susceptible of heat, light, and magnetism is susceptible to these influences; the child who as yet does not know anything, can know something, and this constitutes the real difference between him and the irrational animal; finally, that alone will become a reality which is capable of existing, and which involves no contradiction in terms. (In this latter case no real power is required, but a possibility is). Therefore, becoming is the transition from potency to act, from indetermination to determination. But the sufficient reason for this transition is not to be found in the transition itself, since it is not unconditioned. Potency does not bring itself into act, and unconditioned union of diverse things is impossible. Therefore, becoming demands an extrinsic actualization or realizing raison d'être, which we called efficient cause (n. 25) when we showed the necessity as well as the twofold validity, objective and transcendental, of the principle of causality (see n. 25 and 29). This realizing raison d'être must itself be real before it can realize, must itself be actual before it can actualize, must itself be determined before it can determine anything. This means that it must actually have that for which becoming is as yet only in potentiality.

See Ravaisson, Essai, sur la Métaphysique d'Aristote, Vol. I. pp. 391 and 394.


To deny this is to assert that the greater can proceed from the less, or, what amounts to the same thing, that being arises out of nothingness. St. Thomas expresses this truth in the formula: "Nihil movetur nisi secundum quod est in potentia ad illud ad quod movetur; movet autem aliquid, secundum quod est actu (nothing is moved except in so far as it is potentially capable of receiving such motion; only in so far as anything is actually in motion, does it move anything else").

Now, if it is impossible that one and the same being can at the same time and in the same sense be both in potency (undetermined) and in act (determined), it is equally impossible that one and the same being in the same sense can be both mover and moved; hence, if it is in motion, it is moved by some other being, unless it happens to be in motion in a certain sense with respect to one part of its being, in which case it can be moved by another part of its being. Such is the case with living beings, and even more so with sentient and intelligent beings. But since the part which moves is subject to a motion of another order, it demands in its turn an external mover. Hence we see that whatever is in motion, is moved by another.

The second proposition: "There is no regress to infinity in a series of movers which are actually and essentially subordinate," is based upon the principle of causality and in no way upon the fact that an infinite and innumerable multitude is an impossibility. With Aristotle, St. Thomas, Leibniz, and Kant we do not see that it is a contradiction to admit a regress to infinity in a series of movers which were accidentally subordinate in the past. It cannot be proved that the series of generations in the animal kingdom or of the transformations of energy had a beginning and are not eternal (see Ia, q. 46, and supra, n. 10). It is contrary to reason to say that an actually existing motion can have its sufficient reason, its actualizing raison d’être, in a series of movers, each one of which is itself moved by some external cause. If all the movers receive that impulse which they transmit, if there is not a prime mover which imparts movement without receiving it, then motion is out of the question, for it has no cause. "You may conjure up an infinite number of intermediate causes, but by this process you merely complicate the series, yet do not establish a single cause. You make the channel longer, but it has no source. If it has no source, then the intermediate causes are ineffective, and no result could be produced, or rather there will be neither intermediate causes nor result, which means that everything has vanished."

Sertillanges, Les Sources de la Croyance en Dieu, ed. in 8vo), p. 65.


To try to dispense with the necessity of a source is the same as saying that a watch can run without a spring, provided it has an infinite number of wheels, "that a brush can paint by itself, provided it has a very long handle."



Such statements are a denial of our first proposition, for they imply that becoming is its own sufficient reason, that the un- conditional union of diverse things is a possibility, that the greater proceeds from the less, being from nothingness, that the conditioned does not have to be explained by the unconditioned.

But there is no need of stopping anywhere in a series of past movers, since they exert no influence upon the actual movement which has to be accounted for; they are merely accidental causes (see n. 9 and 10). The principle of sufficient reason does not compel us to terminate this series of accidental causes, but to get away from it, in order to rise up to a mover of another order, not pre-moved, and immobile in this sense, that immobility is not of potency, which is anterior to motion, but that it is of act, which has no need of being subjected to the process of becoming because it already exists. (Immotus in se permanens).

By applying these two principles to motion of any kind, we at last come to admit the existence of a prime mover which is in no way set in motion by another. We must draw special attention to the fact that physical motion, not so much as motion, but insofar as it is physical, only demands an immobile mover from the physical point of view, for instance, a world-soul. But is this soul itself the subject of a spiritual motion, is it the substratum of a process of becoming? This appearance of something new, this fieri (becoming) presupposes in the soul the presence of a potency or faculty which was not its activity, in fact, which was not even in action, but merely had the power to act. Therefore, the intervention of a higher cause was necessary to set it in motion. If this higher mover is itself set in motion, then the question rests. In a series of essentially subordinate movers we must finally arrive at one which is its own principle of motion, and which can explain the entity of its own action. But that alone can explain the entity of its action, to which the action belongs intrinsically, not only as a potency, but also as an act, and which, consequently, is its own very action, its very activity. Such a mover is absolutely immobile in this sense that He has by and of Himself that which the others acquire by motion. Therefore, He is essentially distinct from all mobile beings, either corporeal or spiritual. This statement constitutes the first refutation of Pantheism, as the Vatican Council expresses it (Session III, c. 1): "Since God is absolutely immutable, He is to be declared as really and essentially distinct from the world." The first mover, being essentially immobile, superior to all motion, is necessarily distinct from the corporeal or spiritual world, which is by its very nature subject to change.

Moreover, such a mover must be self-existing; for that alone can act of itself which exists by itself; "operari sequitur esse et modus operandi modum essendi" (action follows upon the nature of a being, and the mode of its action is according to the mode of its being); in other words, for a being to contain within itself the explanation of the entity of its action, it must be self-existing (Ia, q. 3, a. 1 and 2; q. 54, a. 1 and 2). Finally, just as A is A, so it must be with what is self-existing in regard to its existence (Ia, q. 3, a. 4). It must be the self-subsistent being, pure being, pure act, absolute identity, the reverse of that want of identity which is found in all becoming. This last-mentioned point will be brought out more clearly a posteriori by the fourth proof for the existence of God.

From the above remarks we see that the principle of identity is not only the supreme law of thought, but also the supreme law of reality. The identity here established is that of immutability, and the fourth proof will establish the more profound attribute of simplicity.

b) It may be of help to the imagination to present the proof for the existence of God drawn from motion by taking an example of subordinate causes which appeals to the senses. "A sailor holds up an anchor on board ship, the ship supports the sailor, the sea enables the ship to float, the earth holds in check the sea, the sun keeps the earth fixed in its course, and some unknown centre of attraction holds the sun in its place. But after that? . . . We cannot go on in this manner ad infinitum in a series of causes which are actually subordinate."

See Sertillanges, Sources de la Croyance en Dieu, p. 65.


There must be a primary efficient cause which actually exists and gives efficacy to all the other causes. It is useless to appeal to the past series of transformations of energy, so as to discover the one which immediately preceded the present condition of our solar system and of the entire universe; these anterior forms of energy are not causes; they were, besides, transitory and as indigent as the actual forms, and just as much in need of explanation as they. If the series is eternal, it is eternally insufficient. We must necessarily admit the existence of a non-transitory cause, one in itself permanently immobile (immota in se permanens), not at the beginning of the series, but above all others, a sort of permanent source of life in the universe, and the origin of all becoming.

This all-sufficing cause could not be material, even if, accepting the theory of the Dynamists, we conceived of matter as endowed with energy and with certain primitive essential powers. The question here at issue is not physical, but metaphysical. Physics, a particular science, considers the cause of motion precisely as motion. We have to consider it from the metaphysical point of view, insofar as it is a manifestation of being. The question remains, therefore, whether this matter, endowed with energy, is an agent that can of and by itself explain the being of its action: in other words, an agent whose power to act is its very action, per se primo agens: intrinsically and immediately operative? (Ia, q. 3, a. 2, 3a ratio; q. 54, a. 1). This is impossible, for, as we have just seen, such an agent cannot be the subject of becoming, and matter is pre-eminently such a subject.

c) This proof from motion may be exemplified in another way by considering motions of the spiritual order, as St. Thomas has done in the article of his Summa entitled, "Whether the Will is Moved by any External Principle?" (Ia IIae, q. 9, a. 4). Our will begins to will certain things which it did not will before; in fact, when striving to attain a certain end, the will, in virtue of this first volition, moves itself to will the means for attaining that end. Thus, a sick person wishes to be cured, and as a consequence decides to see the doctor. But the will was not always actuated by this superior tendency towards an end. Since to be restored to health is something good, the will began to wish for this good. Moreover, this actual willing of what is good is an act distinct from the faculty of willing. Our will is not an eternal act of loving what is good; of itself it does not contain its first act except in potentia, and when it appears, it is something new, a becoming. To find the realizing raison d'être of this becoming and of the being of this act itself, we must go back to a mover of a higher order, to one that is its own activity, determines itself to act, and, therefore, is self-existent Being itself. Only self-existent Being can explain the entity of a becoming which does not determine itself. "Therefore we must of necessity suppose that the will advances to its first movement in virtue of the instigation of some exterior mover, as Aristotle concludes in his Eudemian Ethics, VII, ch. XIV" (Ia IIae, q. 9, a. 4). Afterwards the will, already in action, moves itself to further acts; but in doing so it functions merely as a secondary cause, always subordinate to the impulse or motion of the first cause.

St. Thomas also proposes the question (Ia, q. 82, a. 4, ad 3um), whether every act of the intellect presupposes an act of the will, applying the intellect to consider what is presented to it. He answers that the first act of the intellect does not presuppose an anterior act of the will, but only that it be moved by the primary intellect. "There is no need to go on indefinitely," he says, "but we stop at the intellect as preceding all the rest. For every movement of the will must be preceded by apprehension, whereas every apprehension is not preceded by an act of the will; but the principle of counsel and understanding is an intellectual principle higher than our intellect, namely, God, as Aristotle also says (Eth. Eudem., VII, ch. XIV). And in this way he shows that there is no procedure in infinitum." See also Ia, q. 2, a. 3, ad 2um; q. 79, a. 4; q. 105, a. 5, where St. Thomas explains that the concurrence of the Supreme Intellect is necessary not only for the first act of the created intellect, but also for each successive act, and hence the secondary cause always remains subordinate to the primary cause, and every movement relating to participation in an absolute perfection presupposes an intervention of God by reason of this same perfection, which is not such by participation. No created mover acts without the concurrence of the prime mover; no created intellect without the concurrence of the primary intellect, and there is no created freedom of action without the concurrence of the primary freedom.

B. Objections. Quite a number of objections have been raised against this proof. The most important of them, which we shall discuss first, concern the first proposition, namely, that whatever is in motion, is set in motion by another (quidquid movetur ab alio movetur). Then we shall examine those objections which deny the necessity, in a series of actually subordinate movers, of finally coming to one that is first. Last of all we shall discuss those objections which directly attack our conclusion and claim to prove that a motionless mover is an intrinsic contradiction, or that such a mover is not to be identified with the true God.

a) The principle, "Whatever is in motion, is set in motion by another," is contested, as far as physical motion goes, by a number of modern physicists, whose philosophy is either (α) mechanistic or (β) dynamistic. As far as psychic motion is concerned, the principle is disputed by some Scholastics, including Suarez (γ). According to certain followers of the philosophy of becoming,

For instance, Abbé Le Roy in the Revue de Métaphysique et de Morale, March, 1907.


it would seem that this axiom derives its apparent lucidity from a spatial image and rests upon the imaginary postulate of the substantial distinction of bodies (δ).

In the physical order, various objections have been raised, attacking the principle, both by the Mechanists and the Dynamists.

α) As for the Mechanists, who follow Descartes, and Democritus amongst the ancients, motion (they mean local motion, the only kind which they admit), is a reality distinct from extension, which, always remaining the same, surrounds extended matter and passes from one body to another. According to Democritus, motion, like matter, is absolute. According to Descartes, God has from the beginning placed in things an in-augmentable quantity of motion, and conserves this motion just as He conserves the things themselves. This mathematical conception of motion, which has passed into modern physics, rejects the question of the relations between motion and being, and consequently also that of the origin of motion, and considers merely its transformations. Descartes has deduced from it the principle of inertia in explicit terms: "If a portion of matter is at rest, it does not begin to set itself in motion; but once it is in motion, we have no reason to suppose that it will ever be compelled to cease moving itself, so long as it does not meet with anything that retards or stops its motion." (Principes, II, 37; Le Monde, VII). He adds that "Every moving body has a tendency to continue moving in a straight line." (Principes, II, 39; Le Monde, VII). This principle, admitted a priori by Descartes, was accepted as the result of experience by Galileo. Newton, Laplace, and Poisson believed in its absolute validity. To-day it is looked upon as a hypothesis suggested, but not verified, by the facts.

See H. Poincaré, La Science et l'Hypothèse, pp. 112-119.


From his concept of motion Descartes deduced what in our present terminology is known as the principle of the conservation of energy. "It is impossible," he said, "for motion ever to cease, or even for it to change, except insofar as it passes from one subject to another;" if it disappears in one form, it reappears in another. (Principes, II, 36).

See E. Naville, La Physique Moderne, 2nd ed., 1890, pp. 86 and 87.


Robert Mayer, the originator of thermodynamics, would say that "the totality of energy in a system in which the bodies are removed from all external influence (the sum of their actual and potential energy), remains constant."

From this point of view, anything that is in motion no longer needs an actual mover whilst it is in motion; it needs him only when it passes from a state of rest to what since Descartes has been called the state of motion (état de mouvement). By local motion a body would acquire nothing; it would merely pass from potency to act, it would merely change its position.

Considering this new theory of local motion as an advance in science, Fr. Bulliot, at a Catholic Congress held in Brussels, in 1894, proposed to use as a basis for the proof of God's existence from motion, not motion itself, but the transition from repose to motion.

See Revue Thomiste, 1894, P. 578.


It has been rightly said in answer to this proposal, that the famous proof in that case is no longer a proof based on motion, but one based on contingency, and in this hypothesis motion, like stable and permanent realities, needs only a conservative cause, but no prime mover. Moreover, many other things are required before the Cartesian idea of motion can be accepted, either from the philosophical or from the scientific point of view, and if it were acceptable for local motion, our proof could still be based on qualitative motions or augmentation.

From the philosophical point of view it cannot be admitted that motion, while remaining numerically the same, passes from one subject into another; neither can it be admitted that energy is a reality which remains numerically the same, though passing in different forms from one subject into another. It is a means by which the imagination of the savant can represent the phenomena, of which all he has to do is to determine what are their permanent relations. The concept thus formed cannot claim to express the intrinsic nature of the realities. It belongs to metaphysics, and not to positive science. Now, from the metaphysical point of view or that of being, "it is false to assert that local motion and heat are something external to the bodies which they affect. Motion and heat are accidents which cannot possibly be conceived outside of a subject. It is the subject which gives them their entity; and they are this motion and this heat because they are the motion or the heat of this subject. To affirm that motion is something which, while remaining what it is, can pass from one body into another, is to affirm a contradiction. Motion does not leave the moving body, it does not communicate itself, but imparts motion to another body; heat does not change its locality, but produces heat within a given circumference."

P. Lacome, "Théories Physiques" in the Revue Thomiste, 1894, p. 96. Consult this same article for the other difficulties arising from the Cartesian theory of local motion, and for the distinction between this latter and qualitative motion (for instance, increase in the degree of heat).


This Cartesian theory of local motion involves other metaphysical impossibilities. Thus we cannot speak of a state of motion. Motion, being essentially a change, is the opposite of a state, which implies stability. There is no less change in the transition from one position to another in the course of movement, than in the transition from repose to motion itself; if, therefore, this first change demands another cause, the following changes demand it for the same reason. To deny that the change which takes place in the course of motion demands a cause, is tantamount to denying the principle of identity or non-contradiction. In fact, this change of position is a successive union of the diverse (of positions A, B, C. . .), and to say that the unconditional union of the diverse is possible is to say that elements of themselves diverse can of themselves be something of a one, that elements which of themselves are not united can be of themselves united and succeed each other. Such an admission involves a denial of the principle of non-contradiction. Generalized and raised to the standard of a supreme principle, this negation implies Evolutionistic Pantheism of the Heraclitan, Hegelian or Bergsonian type (cfr. supra, n. 4 and 21), in which becoming is its own sufficient reason. All theories which, like that of Descartes, refuse to study becoming as a function of being, which alone is intelligible of and by itself, regard it merely as a function of repose. The state of repose may be inferior to becoming, that is, to the terminus a quo kind of repose, which means the point that marks the beginning of motion. Being is always superior to becoming; that which is, is always more than that which is becoming, and which as yet is not. Being is the efficient and final cause of becoming, but of itself postulates neither an efficient nor a final cause. The Mechanistic theory, which considers motion as local, may well study it as a function of repose; but metaphysics, which considers local motion precisely as motion, as a process of becoming, must study it as a function of being, which is its formal object.

Another philosophical impossibility, which arises from the preceding one, consists in explaining how a finite and minimum impulsion could produce an infinite effect, i.e., a perpetual motion, in which there would always be something new, a perpetual absence of identity. Aristotle was more to the point when he demanded an infinite potency for a motion which is infinite in duration. (Cfr. Physics, Bk. VIII; Comment. of St. Thomas, Lect. 21; and Cajetan's opuscule, De Dei Gloriosi Infinitate Intensiva) .

It is true that the Aristotelian idea of motion, which is applied without difficulty to either qualitative or augmentative motion, cannot at first glance be easily reconciled with the motion of projectiles which continues after their impulsion. (Cfr. Physics, Bk. VII, Lect. 3; Bk. VIII, Lect. 22: "Whether the Motion of Projectiles can be Continuous?") The explanation given by Aristotle is obscure; he has recourse to the propulsive elasticity of the circumambient air, which would sustain the projectile in its motion. St. Thomas is much clearer when he states that there is in the projectile a force or instrumental power imparted to it by the principal agent.

"An instrument is said to be moved by the principal agent, so long as it retains the power imparted to it by the principal agent: hence an arrow continues on its course so long as it retains the impulsive force imparted to it by the projector." De Potentia, q. 3, a. 11, ad 5um.


It has been admitted by a number of Scholastics and some Thomists, Goudin for instance,

Physica, I, disp. 3, q. 1, a. 6.


that the initial impulse generates in the projectile an impetus, a force capable of serving as motor. This explanation safeguards the universal principle that "whatever is moved, is set in motion by another." In fact, as Goudin remarks, "by reason of the impulse given to the projectile it is not at the same time and in the same sense in potentiality and in act; it actually has this impetus, but it is in potentia with regard to the position towards which it is tending." In other words, the projectile is in act so far as its dynamic properties are concerned, and in potentia with regard to its future positions in space. Thus all contradiction is avoided. This idea of an impetus, which may be mathematically expressed as a vital force, seems destined to play an essential role in the metaphysics of local motion, the purpose of which is to show that the principle of inertia, as to what there is of experimental truth about it, is itself subordinate to the principle that "there is no change without a cause."

The principle of inertia is incontestably true, insofar as it affirms that inanimate bodies are of themselves incapable of modifying their state of rest; in truth, only living organisms are able of themselves to act and set themselves in motion. But that the motion once imparted to a body continues indefinitely, is a convenient fiction for representing certain mathematical or mechanical relations of the astronomical order; from the philosophical point of view it is seriously to be contested. (See J. Maritain, La Philosophie Bergsonienne, Paris, 1914, p. 143).


For the rest, the principle of inertia, insofar as it affirms that an imparted motion continues without a cause, cannot be verified by experience. H. Poincaré, in his work La Science et l'Hypothèse (pp. 112 ff.), has made it clear that this principle is neither an a priori truth, "susceptible of being deduced from the principle of sufficient reason," nor a truth demonstrated from experience, as Newton thought it was. "Has it ever been proved from experiments with bodies removed from the influence of all external force, that these bodies are not influenced by any force?" This hypothesis was suggested by some particular facts (projectiles), and "extended without fear to the most general cases (in astronomy, for instance), because we know that in these general cases experience can neither confirm nor deny it." (Ibid., p. 119). The same has been said of the principle of the conservation of energy: "In a system of bodies removed from all external influence, the total energy of this system remains constant." It has never been possible to withdraw a system of corporeal beings from the influence of invisible forces, such as that of God or of free will,

See Boutroux, De la Contingence des Lois de la Nature, 3rd ed., pp. 75-85; De Munnynck, "La Conservation de l'Energie et la Lrberté Morale" in Revue Thomiste, 1897, pp. 115 ff.


and, above all, it has never been and never will be proved that the whole universe is a closed system.

See E. Naville, La Physique Moderne, 2nd ed., pp. 35-42.


Therefore we maintain that the Aristotelian definition of motion as a transition from potentiality to act is applicable to local as well as to the other physical motions (either qualitative or augmentative); in other words, local motion is no more a state than the other motions; it is a process of becoming. Hence this proof for the existence of God can start from motion as its principle.

Against those who refuse to see that there is question of becoming in local motion, it would be possible, it is true, with Fr. Bulliot to take the transition from the state of rest to motion as the basic principle in the argumentation and say with Paul Janet,

Le Matérialisme Contemporain, p. 51.


that if bodies are equally indifferent with regard to rest as to motion, there must be some reason to account for the fact that they are more often in motion than at rest, and this reason cannot be in the bodies. Moreover, we may argue from this fact that bodies are contingent. If they are equally indifferent with regard to rest and to motion (since it is only in one of these two states that they can exist), we must conclude that they have not the reason of their existence in themselves, but postulate an extrinsic cause.

If it is claimed that local motion can be explained by another form of energy, such as heat, then this is merely delaying the question. This anterior form of energy is not numerically the same reality as that which exists in local motion, but it is a reality of the same kind, likewise transitory, requiring just as much an explanation as local motion and every preceding form does. It matters not whether the series of transformations is eternal, for it would be eternally insufficient. Hence we come back to our proof, which is that, to account for these transformations, there must be a mover which is not transitory itself, and which not only can come into action, but which goes into action by itself, and contains the source of its activity within itself. Such a mover cannot be anything material, for, unlike matter, it cannot be the substratum of any becoming, but possesses primarily and essentially everything that is gradually acquired in the process of becoming. The principle of the conservation of energy is not, therefore, any more in conflict with the proof from motion than is the old principle that "the corruption of one thing means the generation of another." The energy remains the same, but not numerically so; a transformation has taken place within it, which is the very reverse of what is permanent and which, like everything that lacks identity, demands a cause.

Moreover, we know that the principle of the conservation of energy has its corrective in the principle of the diminution of energy. Mechanical energy, when transferred into thermic energy, cannot be restored in equivalent quantity; thus more mechanical energy is absorbed for the generation of heat than can be given back by it. Some thought it possible to deduce a proof for the existence of God from this principle. If the world thus approaches a state of equilibrium and final rest, they argued, it is because motion is not necessary, and therefore, must have an extrinsic reason, a cause.

See Hontheim, Theologia Naturalis, n. 336.


This is an argument ad hominem,

Chossat in the Dict. do Théol. Cath., art. "Dieu," col. 938.


and is worth just as much as the principle of the diminution of energy is worth. Accepting Duhem's warning at the Brussels Congress, let us not "have recourse to disputed theories of physics in establishing the laws of metaphysics.”

Cfr. Revue Thomiste, 1894, p. 579.


In matter of fact we need not have recourse to the principle of the diminution of energy in order to preserve the true meaning of the proof of the prime mover against the Mechanists, who, like Descartes, are content with a brief allusion to the origin of things in the past. In all becoming there is something new, which demands, not a creative evolution, but the intervention of the Primary Being.

β) Certain Dynamists present an objection which directly contradicts the principle that whatever is moved is set in motion by something else ("quidquid movetur, ab alio movetur"). They admit with us against Descartes, that motion is not imparted ready-made to an object by some external force, but their reason is that they do not see the necessity of admitting an external mover and view the activity of inanimate things after the manner of living organisms. According to Schiller, "the proofs based on motion and on causes are possible only if we accept a Mechanistic hypothesis for the world; in a Dynamic system of philosophy they are of no value."

See Revue de Philosophie, 1906, p. 653.


We ask: Did Aristotle and St. Thomas teach Mechanism?

This objection does not affect our principle, which is true even of living organisms. A living organism cannot, without contradiction, be in the same sense both mover and moved; it is moved by one part of itself (its members), and another part of it (the heart and the nerve centres) acts as mover; but this other part, being the substratum of a motion, demands an external mover, and in the final analysis, a mover not subject to any process of becoming.

γ) The Dynamists think they can explain away the force of this argument by admitting a force which acts as an intermediary between potency and act, and which can bring itself into action. This force is the virtuality spoken of by Leibniz and the virtual act by which Suarez

Disp., XXIX, sect. 1, n. 7.


believed he could explain how the will can bring itself into action without a divine impulse. In the system of Dynamic philosophy this objection ranks as final.

John of St. Thomas, In Iam, q. 2, disp. 3, a. 2, no. 6; Leibniz, Monadologie, ed. Boutroux, pp. 39-41; Kleutgen, La Philosophie Scolastique, Vol. III, p. 329; Duhem, L'Evolution de la Mécanique, p. 36.


We can easily answer this objection by saying that the virtual act is distinct from the action which results from it. Is there, or is there not, a trace of becoming in this act? Is its action eternal, or, on the contrary, did it come about in time? This appearance of something new, this process of becoming, presupposes an active potency which is not the source of its activity, which did not even bring itself into action, but which only proves that it could come into action. And then, how are we to account for the transition of this virtual act to the second act, which previously was non-existent? To say that it effects this by its own power is to posit an absolute beginning, which is contrary to reason. The greater does not come from the less, nor being from nothingness. Therefore, the virtual act has been brought into existence by an external mover, which, in the final analysis, must be its own Activity, and cannot be the substratum of any becoming.

See Gardeil, "L'Evolutionisme et les Principes de St. Thomas" in Revue Thomiste, 1893, pp. 323 ff. See also Revue Thomiste of 1899, p. 293.


We see, then, how false it is to say with Hébert

Revue de Métaphysique et de Morale, 1902, p. 398.


that the apparent clarity of the principle, "Whatever is moved is set in motion by something else, is based upon a spatial image illegitimately introduced into a metaphysical problem;" or to assert with Le Roy,

Rev. de Mét. et de Morale, March, 1907.


that this axiom rests upon a postulate of the practical imagination, according to which there are movers and moved objects substantially distinct. One recalls to mind that famous postulate of morcellation: The distinctions between mover and moved, between motion and its subject, and the affirmation of the primacy of act over potency, all proceed from the same postulate of common thought. . . . Criticism shows that this morcellation of matter is but the result of a mental process, prompted by the dictates of practical utility and discourse. . . . If the world consists of an immense continuity of unceasing transformations, it is no longer a question of a graduated and innumerable series of beings which necessarily calls for an absolute beginning. . . . In affirming the primacy of act, these same postulates are understood. If causality is but the outpouring of a fullness into a void, a communication to a receptive term of that which another term possesses, in a word, if it is the anthropomorphic operation of an agency, then well and good! But what do these idols of the practical imagination amount to? Why not simply identify being with becoming? . . . As things are motion, there is no longer any need of asking whence they derive motion."

Le Roy, ibid.


Motion not only does not demand an explanation, but it explains everything else. Nominalistic Sensualism can scarcely put the case differently.

We may refuse to go beyond the limits of this Empiricism, and rest with Heraclitus and Bergson in the πάντα ῥεί or universal flux of things; but if we wish to find an intelligible interpretation of the real, if we wish, without denying the process of becoming (as Parmenides did), to conceive this process as a function of being, which alone is intelligible by itself, what other explanation is there than that given by Aristotle, who declared that what already is, cannot become; nothing comes from nothingness? Nevertheless, there is such a phenomenon as becoming. Where does it come from? It comes from a certain milieu intermediary between determined being and pure nothingness; in other words, it comes from undetermined being or potency. Now, potency not being the same as act, it cannot be actualized or determined except by a being which is in act. The principle, "Whatever is moved, is set in motion by something else," therefore, far from being based upon a spatial image, is based upon the very nature of becoming, rendered intelligible not by reason of corporeal being, but of being itself, which is the formal object of the intellect. Thus this notion and this principle can be applied to a becoming which has nothing spatial about it, as in the case of the will. The division of being into potency and act, which is necessary in order that becoming may be rendered intelligible, may well be called a morcellation; but it is not a utilitarian morcellation of the sensibly continuous, but a morcellation of intelligible being, which, as we have seen (n. 21), must be admitted under penalty of making ourselves ridiculous by interpreting, as Heraclitus and Hegel did, the supreme law of the real in such a way that it becomes an absurdity.

"Why not simply identify being with becoming?" asks Le Roy.

Rev. de Mét et de Morale. March, 1907.


For this very good reason that becoming is not, like being, intelligible by itself. Becoming is a successive union of diverse elements. This union cannot be unconditional, for diversity, of itself and as such, cannot be one. Becoming is the transition from indetermination to determination, and hence presupposes a determinate cause; to deny this is to say that nothingness can be the cause of being, which is a denial of the principle of identity and a setting up in its place of the principle of Pantheism.

On this subject consult J. Maritain, La Philosophie Bergsonienne, Paris, 1914, especially the chapters on the criticism of the intellect, intuition, the duration of time, God, and Bergsonian evolutionism. The author, a former disciple of Bergson, gives us the spirit of Bergsonism, and not merely the letter. He sets before us in bold relief the fundamental principles of this doctrine and shows how they contradict the first principles of reason, the explanation of which constitutes the most important part of the general metaphysics of Aristotle and St. Thomas. This same work contains an excellent exposé of the Thomistic teaching on intellectual intuition, of the proofs for the existence of God and of free will. M. Maritain later expressed full agreement with the Thomists on these questions.


Our proof, therefore, in no way presupposes the numerical distinction of substances, which Hébert and Le Roy assert. Even if the world were but one substance, as long as there is in it such a thing as becoming, it demands a mover which is not the subject of any becoming, and which consequently is distinct from it. Diversity presupposes identity in things, the changeable presupposes the permanent, and the undetermined, the determined. In this there is no question of spatial imagination nor of anthropomorphism (see n. 23). Seek not for the permanence which matter or force intrinsically calls for; it is too evident that they do not possess that attribute, since this matter and this force transform themselves, and this transformation, which is added to their permanence, demands a cause which in itself is not the substratum of the transformations. The principle, "Whatever is moved, is set in motion by something else," loses none of its validity.

b) Let us now pass on to the objection raised against the principle of ἀνάγκη στήναι, that we must finally arrive at the first in a series of movers which are essentially and actually subordinated to one another. It is clearly not a question of a series of movers which were accidentally subordinated to each other in the past. The necessity of coming to an end in this series cannot be demonstrated, but only that we must terminate the series (Ia, q. 46). The objection that arises here is the same as that which Aristotle proposed to himself, namely, may it not be a case of a vicious circle in the causes—so that the prime mover would be the moved in a kind of motion different from that in which it is the mover? Thus the intellect moves the will in the order of specification by placing the good before it, and the intellect is moved by the will in the practical order by directing the intellect to consider this same good. "Causae ad invicem sunt causae in diverso genere," i.e., causes mutually interact, though in a different order.

To answer this difficulty it will suffice to show that there can be no vicious circle here in the same genus of causality. The cause would have and would not have what is required for causation. It would and would not presuppose its effect. If the warmth of the earth depends upon the radiation of solar heat, the latter cannot depend upon the former. If the intellect is prompted to act by the will, the latter cannot, from this same point of view, depend upon the intellect. Now, in the order of efficient causality the prime mover demands, both for psychic and for physical movements, that, inasmuch as it is prime mover, it must be self-existent; for only that acts of itself which is self-existent, since action presupposes being, and the mode of action follows the mode of being. It cannot, therefore, be dependent in its being and action upon any of the subordinate causes, since all these causes depend for their action upon the being and action of this same prime mover. In the order of efficient causality all that is required is that there be no vicious circle to enable us to establish the existence of a prime and uncreated mover, who, as such, cannot be dependent in any other order of causality (objective or final).

c) We come finally to a consideration of the objections which directly attack our conclusion that "there is a prime mover not moved by any kind of motion, whose very action and, consequently, whose very being is unconditioned, and who is none other than the true God." Some claim that a motionless mover is a contradiction, while others assert that such a mover is not necessarily transcendental, distinct from the world, or identical with a personal God.

A motionless mover would be a contradiction; for who says "mover" says "beginning," and beginning is opposed to immobility (Kant's fourth antinomy). This objection is presented in all its force by Penjon in his Précis de Philosophie. After having decided with Spir, that the unconditional union of diverse elements is an impossibility, and that, for this reason, every change (the successive union of the diverse) demands a cause, he concludes: "There can be no connection between a being identical with itself and a change which postulates a cause only and precisely for this reason that there is no point of contact between it and the absolute and invariable nature of things. Only, from the fact that a change has taken place, another change must occur to account for this one, and so on in an indefinite regression."

Précis de Philosophie, p. 112.


"Far from positively affirming the existence of a prime mover and a first or absolute cause, the principle of causality necessarily excludes it."

Ibid., p. 471.


Aristotle was fully aware of this objection, and even though he did not go so far as to admit the idea of creation (the production of all being or of being as the being of things), and especially the idea of a free creation, he admitted that the series of changes is infinite in the regressive order (a parte ante) and that the world and the changes therein exist from all eternity (ab aeterno; Physics, Bk. VIII; Comment. of St. Thomas, Lect. 1 and 2). But for all that he did not deny the fact of a prime mover. He would have replied to the above-quoted objection by saying that all these past changes are not the cause of the actual change, and exert no influence upon it; nay, more, since each of these changes has not its sufficient explanation in itself, it cannot be the reason for subsequent changes. A prolongation of the series does not change the nature of them: ten thousand idiots do not make one intelligent man. Since the union of the diverse has not its sufficient reason within itself, it demands an explanation outside of itself, and since the union of the diverse cannot be explained by anything within itself, it presupposes a unity of a higher order; the multiple brings us back to the one which is intelligible in and by itself. The fact that we regard it as mysterious that the multiple results from the one, and motion from the motionless, does not justify us in denying the existence of this higher cause. It is absolutely required by the principles of our reason and by the mobile and multiple beings of the lower order of which we have direct and certain knowledge. Moreover, the higher cause, which we know only indirectly and inadequately by its effects, must remain obscure for us, and the proper manner of its action must escape our detection. We have no positive knowledge of this mode, as it is in itself, but know it merely in a negative and relative manner, as when we say that it is an unmoved mover or the prime mover. What is this divine causality in itself? It is a mystery. But the obscurity in which it is wrapped, so far as we are concerned, should not cause us to doubt the certainties which lead us up to it, especially if these certainties give us due warning that they can only end in obscurity and that the mystery will remain.

For the rest, Aristotle did not consider himself dispensed from the obligation of proving that there is nothing repugnant in the idea of a motionless mover. He proves this point in his Physics, Bk. III; Comment. of St. Thomas, Lect. 4.; Bk. VIII, Comment. of St. Thomas, Lect. 9. He even goes so far as to prove that every mover as such [per se] is immovable, and movable only per accidens, just as it is per accidens that an architect is a musician. To understand his reasoning, we have but to rise above the imagination and define the action of the mover as a function of being, and not as a case of local repose. To move means to determine, to actualize, to realize; it is accidental for that which determines to have been itself determined (e. g., for that which heats to have been itself heated). How indeed, could that which is still in the stage of becoming and as yet is not an actuality, move something else? The previous changes referred to in the objection are, therefore, but the accidental cause of the actual change. What is necessarily demanded of a mover is that it be in act; a thing must be hot before it can heat something else; in order to teach, one must actually have knowledge. If, therefore, a being is by its nature determined and in act, if it not only can act, but if it is its own action, it will act of its own accord, not having to be moved by another. From this superior point of view such a being will be immobile, not with the immobility of inertia, but with the immobility of supreme activity. There is nothing for it to acquire, since it has of and by itself, and all at once, everything which it can have and which can accrue to it from without. Just as diversity presupposes identity, and as the multiple presupposes the one, so also the undetermined presupposes the determined, and the transition from potentiality to act presupposes the pure act. If the change is that of being in the stage of becoming, it must necessarily have its reason in the being which is and which has no need of becoming. How could a being in the act of becoming be the cause of becoming in another? Can the child which is not yet born, procreate? Penjon has confused the immobility of potency with that of act; the former cannot account for motion, because it is inferior to it: the latter, on the contrary, is superior to motion, and for this reason can explain it.

It is said that while a motionless mover may have been moving from eternity, as Aristotle held, it could not have begun to move. We shall reply to this objection by showing that the "prime mover" by its very definition means that it is eternal, and that its action dominates time, which is the measure of motion.

Thus we see how it is that this prime mover, which cannot be the substratum of any becoming, is transcendental and essentially distinct from the world, which is by its very nature changeable. If we note further that this prime mover is not confined to beings of the material order, but also controls those endowed with intellect and will, we already have the personal God, "in whom we live, move, and have our being."

Acts XVII, 28.


The God to which the proof from motion leads us, is not, therefore, so far removed from the God of whom St. Paul speaks and of whom the liturgy sings:


Rerum Deus tenax vigor

Immotus in te permanens.

(God, powerful sustainer of all things,

Thou who dost remain permanently unmoved.)


C) The results of this proof from motion.—From this argument we conclude that the prime mover must be: (1) pure act; (2) infinite; (3) incorporeal and immaterial; (4) intelligent; (5) omnipresent; (6) eternal, and (7) unique.

(1) The prime mover is pure act, that is to say, there is nothing potential in him. We have already excluded all potentiality in the order of action. The prime mover not only can act, but its action is identical with itself. Also there cannot be any potentiality in its being, for "operari sequitur esse et modus operandi modum essendi," that is, first comes the nature of a being, and then its operation; and the mode of operation follows the mode of being. That which is self-operative must be self-existent. If there were in this prime mover a transition from non-being to being, this could be so only in virtue of a higher cause, and then we should no longer have the prime mover (Ia, q. 3, a. 1, 2, 4). In considering the fourth proof of God's existence we shall see that the self-existent being must be the Supreme Being (see n. 39 a).

(2) The prime mover is infinitely perfect, because pure actuality without any admixture of potentiality. And this is equally true whether we consider the essence or the action of such a being (Ia, q. 4, a. 1 and 2; q. 7, a. 1). Act means the determination of being in point of accomplishment and perfection; pure act is, therefore, pure perfection. It is at the same time pure being; pure intellection, always in act, of pure being always actually known; pure love, always in act, of the plenitude of being always actually loved.

(3) The prime mover is immaterial and incorporeal. Immaterial because matter is essentially a potential subject, susceptible of change, pre-eminently the subject of becoming. The prime mover, on the contrary, is pure act, without any admixture of becoming. He is not corporeal, since He is not material. Besides, a body is composed of parts and depends on its parts, whereas the pure act excludes all composition and dependency. In Him there can be no question of more perfect and less perfect, as is the case with the whole and its parts. Because He is pure act, He is pure perfection (Ia, q. 3, a. 1 and 2; Physics, Bk. VIII, Lect. 23).

(4) The prime mover is intelligent. We know this not only a posteriori, because He moves the intellects (Ia, p. 79, a. 4), but also a priori, because immateriality is the basis of intelligibility and of intelligence (Ia, q. 14, a. 1). It will be the special task of the fifth proof of God's existence to establish the reality of this attribute (n. 40).

(5) The prime mover is omnipresent, because to move all beings, whether spiritual or corporeal, He must be present, since these beings do not move themselves, but are moved by Him. "He works in every agent," writes St. Thomas (Ia, q. 8, a. 1; q. 105, a. 5). The Prophet Isaias proclaims this truth as follows: "Lord, thou hast wrought all our works for us." (Is. XXVI, 12).

(6) The prime mover is eternal, for He has always, by and of Himself, had His own being and action without any change. His action is not measured by time, since in Him there can be no succession. It is only the effect of this action which can be said to occur in time, because it is only this effect which can be said to be successive. In this there is no contradiction. Since this eternal action is superior to time, it creates time as a modality of its effects (see Ia, q. 10, a. 2).

(7) The prime mover is unique, because pure act cannot be multiplied. Anything which would bring about a differentiation in pure act, so as to make two or several pure acts, would set a limit to the perfection of pure act, and thus destroy it.

Moreover, a second pure act could be nothing more than the first, and would be superfluous. Could there be anything more absurd than a God who is superfluous? (Ia, q. 11, a. 3). In the fourth proof for the existence of God not only this attribute, but also that of infinite perfection, will be conclusively proved.

On this deduction of the attributes of the Prime Mover see Aristotle, Metaphysics, Bk. XII, ch. 6, 7, 9, 10.



37) Proof by means of efficient causes.


The point of departure of this proof is not becoming, but being, which is the termination of becoming and which remains after it. In the article entitled: "Whether Creatures Need to be Kept in Being by God?" (Ia, q. 104, a. 1), St. Thomas distinguishes clearly between becoming (fieri) and being (esse). See also Ia, q. 104, a. 2: "Whether God Preserves Every Creature Immediately?"

Certain agents are the cause of the becoming of their effect, but not directly of the being of this effect. Thus a father is the cause of the passive generation of his son, but he may die, while the son continues to live. Other agents are the causes both of the becoming and of the being of their effect, and any cessation in their action could only mean that the corresponding effect ceased to exist. The generation of an animal depends not only upon the male parent of the species, but also upon the numerous conditions and cosmic influences which are necessary for its conservation. The effects of atmospheric pressure upon the organism are a sufficient illustration of this truth. Any notable decrease or increase of this pressure causes great uneasiness in the organism, due to the lack of equilibrium between the elastic force of the internal gases and the external pressure. If this pressure were to be completely removed, the walls of the organism would collapse under the action of the internal gases. Likewise, if solar heat is eliminated from animal life, even the most vigorous of animals will soon die. "Remove the chemical activity from the air which the animal breathes, or from the food which it assimilates, and it perishes at once. This animal existence is of such a nature that, while at first sight it appears to be independent, it is, on the contrary, at every moment of its existence, actually dependent upon a vast number of influences."

Sertillanges, Les Sources de la Croyance en Dieu, p. 70.


Such is the basic principle of this second proof. It is no longer expressed by saying that "It is certain and evident to the senses that in this world some things are set in motion," but by saying that ‘In these objects of sense perception we find that there is a certain order of efficient causes. "For instance, all the cosmic influences are necessarily subordinated to the production and conservation of a mere gnat.

But these causes, as St. Thomas remarks, cannot, in their turn, cause themselves, for before anything can be a cause of something else, it must be first in existence. As St. Thomas says: "Non est possibile quod aliquid sit causa efficiens sui ipsius, quia sic esset prius seipso, quod est impossibile." (It is not possible for anything to be the efficient cause of itself, because in such a case it would have to exist before it actually exists, which is an impossibility). If, therefore, the above-mentioned causes are not self-existent, their existence depends upon higher causes, and so forth. But we cannot proceed ad infinitum, but must finally arrive at a primary cause, itself uncaused, which has being from itself, which it can give to, and preserve in, others, and without which nothing that actually exists could continue to exist. "Examine separately each of the cosmic influences necessary for the conservation of an animal, and you will find that it is itself the result of a series of subordinated causes, either known or unknown, but of which the existence is certain; and this series will permit you to ascend from ring to ring, not in the past, but in the present, until you finally arrive at the primary source of all activity, without which the animal itself and all vital functions as well as all causes which condition them could not exist."

Sertillanges, ibid.


What is the validity of this proof? Its basic principle is no less certain than that of the preceding proof. Just as there is a becoming, so also there are permanent and dependent existences. Starting from this as an established fact, the two principles by means of which we prove the existence of a first cause are nearly the same as those by which we conclude that there is a prime mover. The first principle is that whatever is caused, is caused by something else; nothing can be its own cause, since for anything to be a cause, it must first exist. The second is that there can be no regress to infinity in a series of essentially and actually subordinated causes. This proof, just like the preceding and succeeding ones, abstracts from the question whether the world is eternal or had a beginning in time. The difficulties that might be raised against it do not differ from those previously examined in connection with the prime mover. If this argument presupposes a morcellation, it is not the utilitarian morcellation of the continuously sensible, but the absolutely necessary morcellation of intelligible being. (See n. 21, 23 and 36, B, δ).

We are thus led to the source of being, to a supreme efficient cause, which has no need of being caused nor of being preserved in existence. It must, therefore, be identified with the prime mover, the source of becoming. Like this latter, and a fortiori, it must be self-operative, nay, it must be its own activity and exist a se.

In starting from the order of sensible things it was sufficient to consider the problem from the general point of view of being, which is common to both the corporeal and the spiritual, and we shall thus be able finally to arrive at a cause which appears not only as the primary productive and conservative cause of bodies, but also as the cause of everything which is not self-existent, of everything which is not its own activity, but passes from potentiality to act.

In fact, the unconditioned cause must be: (1) pure act; for, whether we consider it in its being or in its operation, in either case it is pure act, since it has never been reduced from potentiality to act (Ia, q. 3, a. 4). By the very fact that it is being a se, we shall see from the fourth proof that it is the Being itself, for that alone is the being a se which is to being as A is to A. (2) It is one, immaterial, intelligent, like the prime mover, and for the same reasons, as the following proofs will establish more clearly. (3) It is omnipresent, since it must come in contact with all beings, not only to move them, but also to conserve them in being (Ia, q. 8, a. 1; q. 104, a. 1 and 2). (4) Its creative power is all-pervading. The Being a se, the Supreme Being, which is the direct cause not of some mode of being (such as heat or light), but of being as such, is the cause of everything which is not its own cause, and it can be the cause of everything which is capable of existing. The Being a se endows everything with reality and is the direct cause of being, just as fire is of heat, and light of illumination; it can endow with reality all things which do not involve a contradiction, just as fire can heat all things which are capable of being heated (Ia, q. 25; q. 45, a. 5).


38) Proof based on contingency.


We have just shown that the source of becoming and of being must be self-existent; but the existence of a necessary being can be proved a posteriori by starting with the principle, not of the dependence of becoming or of being on its causes, but of being considered in itself as contingent.

We observe that some beings are contingent, that is to say, do not exist forever, but, on the contrary, are born and die. Of such a nature are the minerals which decompose or form a constituent part of fresh matter, such as plants, animals, and human beings. This we know to be a fact. From it we proceed to deduce the existence of a necessary being, of one which always existed a se and cannot cease to exist. It is only a self-existent being that can explain the existence of beings which can either exist or not exist. The principle upon which this proof is based is the metaphysical principle of causality in its most general form. It may be stated as follows: That which has not a sufficient reason for its existence in itself, must have this reason in something else. And this other being, in the final analysis, must exist of and by itself, for if it were of the same nature as contingent beings, far from explaining the others, it would not be able to explain itself. And—we say it again—it does not matter whether the series of contingent beings is eternal or not; if it is eternal, it is eternally insufficient, and always demands a necessary being.

St. Thomas develops this proof more fully by taking into consideration the time element. After having established the existence in the world of beings which begin to exist, and then cease to exist—that is to say, of contingent beings—he remarks that if there were none but contingent beings, it would be impossible for them to have existed always. To exist without a beginning cannot properly be said of any but self-existent beings, and this could not apply to a series of contingent beings, unless they received their existence from a self-existent, or, in other words, from a necessary, Being. Hence, if there were in existence only contingent beings, there must have been a time when nothing at all existed. Now, "if at any particular moment nothing actually exists, then nothing can ever come into existence." Therefore, some necessary being must exist, that is to say, one which cannot not exist; if this being has not its necessity from itself, it derives its necessity from something else. But we cannot continue to proceed indefinitely in this process of dependence of being upon being, and hence we must conclude that there exists a Being which is necessary of and by itself, and which explains the being and continuance of everything else.

The objection is often raised that this demonstration makes scarcely any advance towards the solution of the problem, because it fails to establish conclusively that the necessary being is distinct from the world and infinitely perfect, but merely proves that there is some thing which is necessary. Cajetan replies that this proof may be considered as sufficient in the strictest sense, as the two preceding proofs established conclusively that the prime mover and the first cause are distinct from the world (because the world is subject to becoming, which the prime mover and the first cause is not), and the succeeding proof will demonstrate a posteriori the unity, simplicity, and absolute perfection of the necessary being.

It is now easy to demonstrate a priori that the necessary being, whose existence has just been proved, is not: (a) either an aggregation of contingent beings; or (b) the law governing such beings; or (c) a becoming underneath the phenomena, or a substance common to them; but (d) it is Being itself, pure being, absolute perfection.

a) The necessary being is not an aggregation of contingent beings. A series of contingent and relative beings, even if it were without a beginning, i.e., eternal, could no more result in an absolutely necessary being, than could a numberless series of idiots result in an intelligent man. "But," it may be objected, "how can it be proved that a being is really and truly contingent? Is it not a semblance of reality, which is the result of our having abstracted it from the continuous whole?"

Le Roy, Rev. de Mét. et de Mor., March, 1907.


The kind of being here referred to, such as plants and animals, is at least a part of the continuous whole, but not the whole; moreover, it is a part which comes into existence and ceases to exist, and, therefore, is contingent. An aggregation of similar parts, even though infinite in time and space, could not constitute a necessary being. For a thing to have a semblance of reality, it would be necessary to add to these parts a dominating principle, be it either the law which governs them, or the process of becoming through which they must pass (creative evolution), or the substance common to all the parts.

b) The necessary being cannot be the law which unites contingent and transitory elements. For this law, in order to be the necessary being, would have to have its sufficient reason within itself and also contain the sufficient reason for all the phenomena that it has controlled, now controls, and will control in future. Now, a law is nothing but a constant relation between various phenomena or beings, and as every relation presupposes the extremes upon which it is based, the existence of a law presupposes the existence of the phenomena which it unites, instead of being presupposed by them. It exists only if they exist. Heat expands iron on condition that there are heat and iron. Energy conserves itself if there is energy.

It is objected that while the application of a law indeed presupposes the existence of phenomena which it unites, the existence of a law is independent of its application. We answer that what is independent of this application is the ideal existence of the law, its existence in a mind, to which there corresponds a hypothetically objective truth (for instance, if there are heat and iron, the heat will expand the iron). But it cannot be claimed that the actual existence of a law is independent of its application and of the existence of the phenomena which it controls. Now, it is the actual existence which the Pantheists have in mind when they say that the necessary being, actually existing, is nothing else but the law of phenomena. Eliminate the contingent existence of phenomena, and this necessary being, which is the law, is no more than a hypothetical truth, which demands an existing Absolute for its foundation (proof based on the eternal verities), but which cannot itself be that Absolute. We have previously shown (n. 10) why heat in itself cannot exist in a state separated from the subject which it affects; its very concept implies a common matter, which cannot be realized without at the same time being individualized.

But the Positivists insist that it is a law which produces the phenomena that explain its presence, namely, the law of the conservation of energy, which is a primordial and universal necessity explaining everything else. If "nothing is lost and nothing is created," as this law affirms, then the necessary being is the material world itself, governed by this law. We have already quoted (see n. 35, towards the end) Boutroux's answer to this objection, as given in his thesis entitled, La Contingence des Lois de la Nature. First of all, to repeat briefly, this law, far from being a primordial necessity, is itself contingent; it does not contain its own sufficient reason within itself, and because of this, it demands an extrinsic sufficient reason, or a cause. If this law were necessary, like the principle of identity, it would not actually exist by itself, but, like every other law, would presuppose the existence of beings in which it is realized—in this case the existence of energy. Secondly, this law, far from being universal, is not even susceptible of strict verification in the inorganic world; biology cannot prove its existence, nor, a fortiori, can psychology. Thirdly, the laws which govern living beings, such as the sentient and the intelligent, cannot be deduced from this law. The combination of elements which produces life and sensation appears as contingent and demands a sufficient reason, which the law of the conservation of energy cannot furnish.

c) The necessary being cannot be the process of becoming (creative evolution) through which the contingent elements must pass, nor can it be their common substance. A well-known objection runs as follows: "Suppose every being, viewed separately, were contingent, it would have to be proved that the whole world, or all beings taken together, were also contingent. Does the real contingency of the world follow from the fact of its imperfection, or from the fact that the idea of its non-existence is not repugnant to reason? This brings us back to the argument of St. Anselm, that God really exists because the idea of his nonexistence is repugnant to reason."

Le Roy, Rev. de Mét. et de Mor., March, 1907; Schiller, in La Revue de Philosophie, 1906, pp. 653 ff.


In the fourth proof we shall establish the conclusion that the world is really contingent by reason of its imperfection. This conclusion may also be drawn from the fact that its nonexistence is not repugnant to reason, and because there is no question here of an unlawful transition from the ideal to the real, as in the argument of St. Anselm. All that St. Anselm, starting from the purely nominal definition of God, could say, was that the most perfect being which can be conceived implies existence as an essential predicate in its definition, that is to say, it exists necessarily of and by itself, and not by another, it is its own existence—if it exists. This proposition is strictly true, but it is purely hypothetical. The mistake St. Anselm made was that he wanted the proposition to be taken as an absolute or categorical one, and concluded from it that God actually exists. On the other hand, the definition of any finite being (even though infinite with regard to time and space, provided that it be not infinite considered as being, potentiality, intelligence, etc.), of a plant, for instance, or of an animal, or of matter, or of a spirit, in no way implies existence in its comprehension. Each of these beings is defined without regard to existence; its essence is conceived as capable of existing, and there are no grounds for asserting that its concept postulates essential existence or aseity. Hence we may legitimately formulate the hypothetical conclusion that if this being exists, its existence is not due to itself. This truth belongs to the ideal order or that of essences, and St. Anselm should have kept within this order.

Moreover, we make so profound a study of the subject in order that we may come to the conclusion that the necessary being can be neither the becoming which forms the substratum of phenomena, nor the substance common to them. In fact, it has been fully established in connection with the proof from motion, that becoming cannot have its raison d’être in itself: (1) because it is a successive union of diverse elements, and to say that an unconditional union of diverse elements is possible is to assert that elements, in themselves diverse and not united, can unite themselves or succeed each other by themselves, which would mean the denial not only of St. Anselm's argument, but also of the principle of identity; (2) becoming is the transition from an undetermined to a determined state; to deny that it needs a self-determined cause, is to say that the greater can come from the less or being from nothingness. The imagination alone can combine the two words creative and evolution, but that which comes into being through evolution is not its own sufficient raison d’être, and for anything to be created, this must be the case. (See Ia, q. 2, a. 3, ad 2um).

Finally, the necessary being cannot be a substance common to all beings, for such a substance would be the subject of becoming. Now, the process of becoming, as we have seen, demands a cause which is not itself subject to that same process. In such a case the necessary being would at any moment be deprived of that which, so far, it does not possess, and which it could not give itself, because the greater does not proceed from the less. The necessary being, which must be the sufficient reason for everything which now exists or will exist in future, may give, but it cannot receive; it may determine, but it cannot be determined; it must have of and by itself and from the start, not only in potentiality, but also in act, whatever it must and can have. Ia, q. 3, a. 6: "Whether there is a Composition of Subject and Accident in God?"

d) The necessary being is being itself, pure being, absolute perfection. Kant

Transcendental Dialectic, ch. III, section 5.


maintains that we cannot argue from the existence of a necessary being that it is sovereign perfection, ens realissimum, except by unconsciously reverting to the ontological proof. He believes that he has proved this point by the simple conversion of a proposition. Let us, he writes, according to the rules of formal logic, convert the proposition, "Every necessary being is perfect," and it becomes: "Some perfect being is necessary." But in that case we should have no means of distinguishing between perfect beings, since each of them is ens realissimum. The converted proposition is, therefore, equivalent to the universal one that "Every perfect being is necessary," which is identical with the thesis of the ontological argument. As the transition from the first proposition to the second is effected by a process which is purely logical and according to rule, the truth or falsehood of the one is dependent upon the truth or falsehood of the other. Such is Kant's principal objection against the classical proofs for the existence of God, considered not according to their basic principle, which is that of causality, but according to that step in reasoning by which they proceed from the first cause to the existence of the perfect Being.

This objection is answered sufficiently by stating that St. Anselm was wrong in concluding that "the perfect being necessarily and actually exists." He ought to have been satisfied with affirming that "the perfect being is self-existent, if it exists." He could just as easily have proved a priori the hypothetical contrary, namely, "if a self-existent being exists, it is sovereign perfection." To establish the truth of this proposition is precisely what remains for us to do, having demonstrated by the argument from contingency that a necessary being actually exists. That the two concepts (necessary and perfect), the very definition of which reveals that they are essentially linked together by their very definition, are equivalent, is a legitimate assumption for those who, unlike Kant, admit that necessary realities correspond to necessary concepts of the mind, and that the unthinkable and the impossible are correlative terms. (Consult what was said supra in n. 17, 18, 19, and 21, concerning the objective validity of the principle of non-contradiction).

It is by the following a priori method of reasoning that the transition from the necessary to the perfect being is effected. We will content ourselves with giving a brief résumé of the teaching of St. Thomas, since the fourth proof will lead us a posteriori to the same conclusion.

1) The self-sufficient being, recognized as actually existing, implies existence as an essential attribute, which means that it must not only have existence, but that it must be its own very existence (Ia, q. 3, a. 4).

1) This being, which is its own existence, cannot belong to any species, nor to any genus; in fact, its genus could not be less universal than being itself, since being is essentially predicated of it. Now, being, which admits of no extrinsic difference, is not a genus (Ia, q. 3, a. 5).

3) This being is sovereignly perfect, because a being which is its own existence must contain within itself the whole perfection of being ("totam perfectionem essendi"). "All the created perfections," says St. Thomas, "are included in the perfection of being; for things are perfect precisely in so far as they have being after some fashion." (Ia, q. 4, a. 2). Every perfection (goodness, wisdom, justice, etc.) is a mode of being which is capable of existing —something which can participate in existence ("quid capax existendi"). Existence is, therefore, the ultimate act of every thing which can exist. It is the maxime formale omnium: the most formal of all things, the final determination placing that which is capable of existing outside of nothingness and its causes. But actuality is superior to, and more perfect than, potentiality; for the former is an absolute, whereas the latter is merely a relative thing. We must, therefore, conclude that being which is its own existence, is pure actuality and absolute perfection.

4) This being is one of infinite perfection (Ia, q. 7, a. 1). In truth, if self-sufficient being were limited in its being, it would merely participate in existence and would be a compound of essence as the limiting and of existence as the limited element. For this very reason, its essence would cease to be its existence, and could be conceived apart from its existence, and hence the latter could no longer be predicated except as something accidental to it. If the essence of the self-sufficient being is in no wise limited (as the being, the intelligence, and the potentiality of a finite spirit are limited), it must a fortiori be said that this being cannot be subject to material and spatial limitations. It belongs to an order which infinitely transcends both space and time, the infinity of which, if it were possible, would never be other than one of quantity, and not of quality, which is the kind here in question. From the foregoing we conclude that just as A is A, so the self-sufficient being must be identical with its existence. The fourth proof will demonstrate this point a posteriori.


39) Proof based on the various grades of being.


The purpose of this fourth proof, as we have already remarked, is to seek for a sign of contingency in the ultimate profundities of created being, which the proof from motion did not touch. Approaching the subject now from the static point of view, we notice that beings happen to come into existence, or else to die. To prove their contingency, we have recourse to an observation which, though less convincing at first sight, nevertheless, has a deep significance and is more universal in its application than either motion, generation or corruption. We refer to the multiplicity of these beings, to their composite nature, and to the fact that they are to a greater or less degree, imperfect. This argument has been called the henological proof (ἑν = one), because it proceeds from the multiple to the one, from the composite to the simple. Kant did not choose to criticize this argument. If he had studied it closely, he would undoubtedly have been less inclined to reproach modern Scholastics for continually falling back, either unconsciously or insincerely, upon the argument of St. Anselm. He furthermore did not perceive that this fourth proof prepares the ground for the fifth, which is that based upon the multiplicity of purpose in things or design in the universe. His objections against this last proof, too, are rather superficial.

Quite recently the following objections have been raised against the argument based upon the various grades of being: (1) The presence of imperfection in the world cannot be alleged as a proof of its contingency, for that would be a return to the ontological argument by combining the idea of necessary existence with that of a perfect being.

Le Roy, Rev. de Mét. et de Mar., March, 1907.


(2) Strictly speaking, the greater and the less are predicated only of quantity, for quantity alone is greater and less. (3) This proof, like the previous ones, is based upon the postulate of morcellation. (4) It is difficult to conceive a typical essence for all things.

We shall see that the henological argument contains no feigned reference to the syllogism of St. Anselm, because this argument in reality is based upon the fundamental law of thought, which is the principle of identity. The supposed morcellation in this case is again that of intelligible being, and not that of the continuously sensible. Finally, a typical essence, separated from matter and of a higher order than the individuals which represent the species and the genera, can be required only for the transcendentals (being, unity, truth, goodness, intellect, vital relation to being, etc.),

We have previously explained (n. 29), that the intellect and the will are not, strictly speaking, transcendentals. For the latter dominate the genera and are verified proportionately in each one of them. Nevertheless, the intellect and the will are defined in relation to a transcendental, either to being or to goodness, and consequently, in their formal concepts, they dominate the genera, although, according to the created mode of their being, they belong to the genus of quality and to the species of potentiality or faculty.


which, by their definition, abstract from everything material, dominate the species and the genera, imply no imperfection in their formal concepts, and are realized analogically in various degrees. (See n. 29).

We shall first study: (a) the proof in its general outline, as sketched by St. Thomas, and we shall show that it leads to a Primary Being, absolutely simple and perfect, and consequently distinct from the world, which is composite and imperfect. This proof will then be more accurately defined by arguing that (b) the series of human intellects, though imperfect, can always advance towards perfection, until at last we come to a Primary Intellect, the source of all the others. (c) From a graduated series of intelligible beings, from eternal truths, we finally come to a Supreme Truth, a primary intelligible, which is the fount of all truth. (d) From the yearning of the human soul for absolute goodness we conclude that there must be a primary desirable object, which is the source of all happiness. (e) From the fact that we feel morally bound to choose what is good and to fulfill our obligations, we argue that there must be a Primary and Sovereign Good, which is the foundation of all duties.

Thus we shall see that the proof based on the various degrees of being, or upon the actually existing and graduated series of transcendentals (being, unity, truth, goodness; intellect, vital relation to being; will, and vital relation to goodness) necessarily implies the proof from the contingency of the mind, based on the perfection of our intellectual and volitional activity. The above-mentioned proof also implies the arguments based upon the eternal verities, upon the sense of obligation which goodness inspires, and upon the yearning of the human soul for the infinitely good. St. Thomas has given us a detailed account of these proofs in his treatise on man (Ia, q. 79, a. 4), at the beginning of the moral part of his theological Summa, where he discusses sovereign goodness and beatitude (Ia IIae, q. 2), and in his treatise on the divine and the natural law (Ia IIae, q. 91).

Here, at the commencement of his treatise on God, he considers it sufficient to present the proof in its most general aspects and to conclude from the various degrees of goodness, truth, and perfection observed in the world, that there is "something which is the true, the good, the noble, and consequently, being par excellence." (Ia, q. 2, a. 3).

a) The proof in its general outline. It is important to determine exactly the starting point of this argument, which is that there are various grades of being. As St. Thomas expresses it: "Among beings there are some more and some less good, true, noble, and the like." (Ia, q. 2, a. 3).

Concerning the point that things can be more or less in a certain respect, one may profitably read the lengthy first article of question 52 in the Ia, IIae, in which St. Thomas explains and discusses the opinions of Plotinus, of the Stoics, and of two other writers quoted by Simplicius. Here, too, he explains how the "more" and the "less" degrees which are predicated primarily of quantity, continuous or discrete, are afterwards legitimately applied to qualities, such as heat and light, which are more or less intense, just as science itself, which is capable of progressing either intensively or extensively according as it becomes broader in its application or penetrates its subject-matter more deeply; for as science is always able to penetrate more deeply into its subject-matter, so also are virtues.

We can readily understand that relative qualities, which derive their specification from an object to which they refer (for instance, science and virtue), are susceptible of the greater and the less, not only with regard to the subject in which they are partially verified, but also in themselves more or less closely approach the term to which they refer.

As for the absolute qualities and characteristics, which bear their specification within themselves (such as being, unity, substance, corporeity, animality, rationality) they are not all susceptible of more or less, even with regard to the subject in which they are partially verified. The specific difference of any species whatever is, indeed, an indivisible. Either one has or has not the ability to reason, which is the specific difference in man; the reasoning faculty, of course, can be used and it can be more or less developed; but in every human being this faculty has the same proper object, namely, the essence of sensible things; the same adequate object, which is being, and the same specific capacity. Likewise, a genus is not, strictly speaking, realized in various degrees; for although it is diversified by specific differences, some of which are more perfect than others, these differences are extrinsic to it. Animality, for instance, or the sensitive life, applies equally to man and lion, for man is not more of an animal than the lion; his animality, as such, is not more perfect, although he is a more perfect animal. In like manner, too, gold is not more a body or a substance than copper; a thing is or is not a substance or a body; it cannot be more or less so.

But when we come to those most general notes known as transcendentals, because they transcend the species and the genera, we notice that they are susceptible of greater and less, and it is these which constitute the basic principle of our proof. These notes (being, unity, truth, goodness), are not diversified, like the genera, by an extrinsic specific difference; for they all apply to that which distinguishes one being from another. We find them verified in each existing being, each in its own way and in different degrees, or, as we say, analogically. Thus, while animality (the sensitive life) applies in the same sense to man and lion; being, unity, and goodness are predicated of different beings on various grounds and in varying degrees. The difference proper to each of these beings is still, in fact, being, since in its own way it is something one and good. A stone is good with its own kind of goodness, in that it does not deteriorate; a fruit is good with its own kind of goodness, in that it refreshes; a horse is good, because it can be used for a race or journey; a professor is good, because he has knowledge and knows how to impart it; a virtuous man is good, because he wills and does what is good; a saint is better still, because he ardently desires goodness, In like manner, too, what is truly good is of a higher order than what is useful or delectable, and an end is in itself better than a mere means thereto. Goodness is, therefore, realized in various degrees. The same is true of perfection or nobility. The plant is of a higher order than the mineral, the animal is superior to the plant, and man to the beast. Again unity applies more to the mind than to the body; for the former is not only undivided in itself, but also indivisible; one society possesses greater unity than another, one science more than another. Likewise, truth is susceptible of various degrees, according to the being on which it is based and the firmness or necessity of the propositions in which it is couched. As St. Thomas points out,

Quaestiones Disputatae, De Caritate, q. 1, a. 9, ad 1um.


truth, being conformity of a judgment with reality, does not admit of greater and less in this respect, for either there is or there is not conformity between the terms. But if we consider the being that is the foundation of truth, there are various degrees for, "the things that are greater in being, are greater in truth"; that which is richer in being is also richer in truth. From the same point of view a first self-evident principle, necessary and eternal, such as the principle of non-contradiction, is truer than a necessary conclusion drawn from it, because it expresses conformity not only with some mode of being, but also with what is found to be more profound and more universal in reality, both possible and actual. A necessary conclusion is likewise truer than a contingent one, not only because it expresses conformity of thought with something transitory, such as the fact that Cæsar is dead, but also because it perfectly corresponds with something eternal, such as, for instance, that man is free.

Apart from any consideration of the scale of beings, we ourselves, in our own lives, are more or less good, true, or noble-minded, in proportion as we live in the way that we ought to live. If there is any question of morcellation here, it is evidently not that of the continuously sensible, and the subtlest criticism of the physical sciences can in no way affect this basic principle.

The actually existing and graduated series of transcendental notes of being, therefore, is the basic principle of this proof. From it reason deduces the existence of a being absolutely simple, absolutely true, absolutely good, a God who is Being itself, Truth itself, Goodness itself, and, consequently, sovereignly perfect. Have we here a veiled recourse to the argument of St. Anselm? Not at all.

The principle by which we argue from the various grades of beings to the existence of God is this: "When a perfection, the concept of which does not imply any imperfection, is found in various degrees in different beings, none of those which possess it imperfectly contains a sufficient explanation for it, and hence its cause must be sought in a being of a higher order, which is this very perfection." As St. Thomas remarks: "More and less are predicated of different things, according as they resemble in different ways something which is the maximum" (Ia, q. 2, a. 3). If we wish fully to understand what is the meaning, the validity, and the range of this principle, which contains in condensed form all the dialectics of Plato, it is Plato himself whom we must consult. The correct meaning which we shall afterwards give to this principle, will prevent us from following him in his exaggerated realism. The dialectics of Plato are the method by which the soul convinces itself of the reality of these transcendentals, or eternal types, which Plato called "Ideas." There is the dialectic of the intellect, which is based upon the principle we have just enunciated, and there is the dialectic of love, which implies the other, though not demanding the same amount of reasoning, and is within the reach of every soul eager for that Goodness which no particular good can satisfy.

This dialectic of love is found towards the end of Plato's Symposium. He says there that the soul must learn to love beautiful colors, beautiful forms, a beautiful body; but it must not stop at any one of these, for they are but a reflection of Beauty. It must love all beautiful bodies and thence proceed to love the soul, which is the principle of the life and beauty of the body. It must attach itself to beautiful souls, beautiful by their actions, and thence rise to contemplate the beauty of the various kinds of knowledge which engender beautiful actions, until, having advanced in knowledge, it finally arrives at that pre-eminent knowledge which is nothing else but the knowledge of beauty itself, and it ends by knowing it as it is in itself. The dialectic of love ends with the natural desire (conditional and inefficacious, says theology) of seeing God face to face and of contemplating "that beauty which is without diminution and without increase; which is not fair in one point and foul in another; which is beautiful only at one time and not at another, beautiful in one relation and foul in another, beautiful at one place and foul at another, fair to some and foul to others; . . . a beauty which does not reside in any other being different from itself, as, for example, in an animal, or in heaven, or on earth, or in any other thing; but which exists eternally and absolutely, by and in itself, which without diminution and without increase, or any change, is imparted to the ever growing and perishing beauties of all other things." (Symposium, 211, C).

This dialectic of love is also discussed by St. Thomas at the beginning of his Ia, IIae, in the Treatise on Happiness, in a series of articles entitled: "Whether Man's Happiness Consists in Wealth, Honors, Fame or Glory, Power, in any Bodily Good, in Pleasure, in Some Good of the Soul, in any Created Good?" His answer is always in the negative, and he maintains that it is only the absolute good

Thus there is natural happiness in God, known by means of His effects, and naturally loved above all things. There is supernatural happiness in God, intuitively known and loved supernaturally above all things.


which can fully satisfy an appetite controlled by an intellect which knows not only some particular good, but good in general. This dialectical method is rigorous and proves apodictically, as we shall see, the existence of the absolute Good, provided we view this method as a simple application of the proof of God's existence which we are studying, and which presupposes the objective and transcendental validity of the first principles of reason.

If, on the contrary, we admit the primacy of the immanent method, if we maintain that, without it, "the dialectic (speculative) subtleties, no matter how long and ingenious, are of no more consequence than the throwing of a stone at the sun by a child;" if it is claimed that "the incontestable presence and the convincing proof of being are the result of action, and of that alone,"

Blondel, l'Action, p. 350.


then no more than practical certitude can result from this dialectic of love, however learned it may be; and this certitude may perhaps be subjectively adequate, but objectively it is inadequate. (See supra, no. 6, and infra, n. 39 d).

But if it is true that the idea of goodness presupposes the simpler, more absolute and more universal notion of being;

"Being is prior to goodness"; Ia, q. 5, a. 2.


if the will and love presuppose the simpler and more absolute activity of the intellect, which merely attains not the good, but also the reason for it;

"The intellect, considered absolutely, is higher than the will," remarks St. Thomas; Ia, q. 82, a. 3.


if the intellect alone can receive being into itself, completely possess it, become one with it; if it is preeminently "the totally intussusceptive faculty," as explained by P. Rousselot in his book entitled L'Intellectualisme de St. Thomas, p. 20; if the will, on the contrary, cannot receive being into itself in this manner, completely possess it and become one with it, but can only tend towards it when it is absent, and take delight in it when it is made present by an act of the intellect

Ia IIae, q. 3, a. 4.


—then the dialectic of love engenders a certitude which is objectively adequate and absolute, and this by reason of the dialectic of the intellect which it implies. And the fundamental principle of the latter is precisely the principle upon which our proof is based: "When there is a greater or less, when there are degrees in anything, then the perfect also exists; if, then, a certain being is better than a certain other, there must be one which is perfect, and this can only be the divine." It is in this way that Aristotle expresses with admirable precision the fundamental procedure in the Platonic process of thought, as presented in his treatise Concerning Philosophy,

Concerning this treatise of Aristotle consult Ravaisson, Essai sur la Métaphysique d'Aristote, Vol. I, pp. 53-69.


in which he gives a résumé of the teachings of his master.

This passage is quoted by Simplicius in his De Coelo (Ald. 6, 67, B); cfr. Fouillée, La Philosophie de Platon, Bk. I, p. 61.


See also the text of Aristotle quoted by St. Thomas in his Commentary on the Metaphysics, Bk. II, ch. 4.

This dialectic principle, which constitutes the major of our proof, includes two other closely connected principles in the system of Plato. To say that there are various degrees of being is to say that there is multiplicity, and also that there is a greater or less degree of either imperfection or perfection. Hence these two principles: (1) If the same note is found in various beings, it is impossible that each should possess it in its own right, and what is not possessed by a being in its own right, is received from another and, therefore, is held by participation; (2) If a note, the concept of which implies no imperfection, is found in a being in an imperfect state, i.e., mingled with imperfection, this being does not possess this note in its own right, but has it from another which possesses it in its own right. By means of this latter principle we argue not only from the multiple to the one, but also from the composite to the simple, and consequently from the imperfect to the perfect.

Let us examine these two principles more closely and see how they are connected with the principle of identity, which is the supreme law of thought.

1) If the same note is found in various beings, it cannot be said that each possesses this note in its own right, and what a being does not possess in its own right, it has from another by participation.

See Plato's Phaedo, 101, A.


Phaedo is beautiful, but beauty is not something which is proper to Phaedo, for Phaedrus also is beautiful. "The beauty found in any corporeal being, is sister to the beauty found in all the others." Not one is beauty, but all merely participate in it, are a part or reflection of it. Phaedo cannot be the source of his own beauty any more than Phaedrus; but the beauty of both must be ascribed to a higher principle, to one to whom beauty belongs by his very nature, who is beauty itself. It is this point which St. Thomas emphasizes when he says: "Multitudo non reddit rationem unitatis" (multitude does not explain the reason for unity). That unity of similitude which is found in multitude cannot be explained by it, but presupposes a higher form of unity. And in his De Potentia (q. 3, a. 5), St. Thomas shows how this principle is connected with that of identity, which is the supreme law of thought and reality: "If one of some kind is found as a common note in several objects, this must be because some one cause has brought it about in them; for it cannot be that the common note of itself belongs to each thing, since each thing is by its very nature distinct, one from the other, and a diversity of causes produces a diversity of effects." Phaedo and Phaedrus cannot possess beauty from themselves; what properly constitutes them as individuals cannot explain why they are beautiful; for the individualizing traits in each of them are different, whereas both have beauty in common; the diversity cannot be the reason of unity. To say that Phaedo and Phaedrus are beautiful in and by themselves, would be to say that the diverse is of itself one with a unity of similitude, in other words, that elements in themselves diverse and not alike, are of themselves alike by reason of that which properly constitutes them as individuals. This would involve a denial of the principle of identity or non-contradiction. There is no recourse here to the argument of St. Anselm,

By means of this principle Plato argued from the multiple to the one, from the multiplicity of individual things to the existence of eternal types of things, to the idea of eternal Truth, eternal Beauty, and eternal Justice. But he found that there was still a certain diversity, which led him to conclude that there is a supreme unity, which is the Idea of ideas, the Sun of the intelligible world, which was for him not the Idea of Being, but the Idea of Goodness, or of the plenitude of being. In the world of knowledge the idea of good appears last of all, and is seen only with an effort; and when seen, is also inferred to be the universal author of all things beautiful and right . . ."

Republic, VI, 109, B.


St. Thomas concludes in almost the same manner: "There is something which is the True, the Good, the Noble, and consequently, Being par excellence, which is the cause of whatever there is of being, goodness, and perfection in all things; we give the name of God to this cause."

It is objected that we can hardly conceive a typical essence for each thing. This difficulty embarrassed Plato, because he failed to distinguish clearly the transcendentals from the genera and species. It is a disputed question whether he made man out to be a separate entity, distinct from the idea of the Good, or whether he considered man to be merely a divine idea. Whatever opinion he held on this point, we may say with Aristotle,

Met., Bk. I, c. IX, Lect. 14 and 15; Bk. VII, ch. X, Lctt. 9 and 10; cfr. St. Thomas, Ia, q. 6, a. 4; q. 65, a. 1, with Cajetan's commentary; q. 84, a. 7; q. 104, a. 1.


that only those characteristics whose formal reason abstracts from everything material, can exist in a state separated from matter and individuals. On the contrary, whatever in its concept implies a combination of material elements, is incapable of existing apart from matter and from the individual in which it is found. Flesh and bones, for instance, are implied in the concept of man. Flesh cannot exist except as this particular flesh; for flesh is something which is necessarily material and extended, and which has certain parts and a certain extent, and not any other. Flesh can be thought of separately (separatim), apart from its individualizing notes, but it cannot exist apart from them (separata).

De Anima, Bk. III; Comment, of St. Thomas, Lect. 12.


The exemplars of material things can never be anything but ideas, not real types. This logical precision applied to Plato's principle saves us from following him in his exaggerated realism.

But the case is quite different with the characteristics which, according to what they formally denote, abstract from all that is material, and which, moreover, transcend the genera and the species, and for this reason are realized analogically in various degrees (as is the case with being, unity, truth, goodness, beauty, intellect. . . .). They can and must exist apart from matter and
from the individuals in which they are found realized, in a being of a higher order who possesses these characteristics in the highest degree.

It is precisely for this reason that our proof does not start with a characteristic found in the same degree in various beings, e. g., humanity. Such a characteristic is of necessity caused not in all save one, but in all.

Cajetan, Ia, q. 65, a. 1.


One of these beings cannot be the first cause of the others, since it is of the same nature with them and just as indigent as they are.

The proof from the degrees of beings does not ascend from the multiple to the one, without at the same time ascending from the composite to the simple, from the imperfect to the perfect. It is not enough to posit as a principle that "if the same characteristic is found in various beings, it is impossible for each of them to possess this characteristic in its own right;" but we must add that "if a characteristic, the concept of which does not imply imperfection, is found to be present in a being in an imperfect state, mingled with imperfection, then this being does not possess it in its own right, but has it from another, to whom it belongs in its own right."

2) This second principle, implied with the first in the major of our proof, has been expounded by Plato in his Philebus, Phaedo, and other dialogues. It cannot be said, he remarks, that Phaedo is beautiful without restriction, or that Socrates is great without restriction;

Phaedo, 102, B.


that the knowledge which men have is a knowledge without restriction. In them these qualities (beauty, greatness, knowledge) are not pure, but mixed with their opposites. In fact, Socrates is both small and great. He is great when compared with Phaedo, small when compared with Simmias, and therefore he has not the greatness which excludes smallness, but merely partakes of greatness in a measure. A man has knowledge of a certain thing and is ignorant of certain other things; his knowledge is mixed with ignorance; it is not knowledge without restriction, but a participated knowledge.

But how shall we proceed from this to affirm the existence of absolute beauty and absolute knowledge? The Cartesians often pass immediately from the imperfect to the perfect; they neglect to resolve these notions into those simpler and nearer to being, composition and simplicity, admixture and purity. That is why the Kantians reproach them for unconsciously having recourse to the ontological argument; in reality the Cartesians appeal to the principle of identity, but they fail to establish this fact.

To say imperfection is the same as saying composition or mixture of a perfection with that which limits it. The limit may be either the opposite of the perfection, as when Socrates is said to be great and small from different points of view; or privation, as when human knowledge which knows certain things, is said to be ignorant of certain others, which, however, it is capable of knowing; or negation, as when a human being has knowledge of certain things and is ignorant of certain others which are inaccessible to it. It makes little difference whether the limit which constitutes the imperfection be contrary, privative, or negative; what we want to know is, why it affects the perfections known as beauty, goodness, knowledge. . . . Evidently none of these perfections in themselves imply a limit, least of all such a limit. In itself, beauty excludes ugliness, knowledge excludes ignorance or error, and goodness excludes egotism. To say that such is not the case would be to maintain that the unconditional union of diverse elements is possible; that the diverse is, of itself, one, at least with a unity of union; that elements, according to what constitutes them as individuals, though they do not necessitate their being united, are of themselves united. This would involve a denial of the principle of identity. If any one of these perfections does not of itself denote a limit, still less does it denote of itself a certain kind of limit, since this limit is subject to variation. There is progress in knowledge, and our goodness is susceptible to increase and decrease.

The union of a perfection with its limit, not being unconditional, therefore, demands an extrinsic raison d'être. "Things in themselves different cannot unite, unless something causes them to unite." (Ia, q. 3, a. 7). To deny this would be to identify that which has not its own sufficient reason in itself, either with what is not self-determined (and has no need of a sufficient reason) or else with what is self-determined (and has no need of an extrinsic sufficient reason). To doubt this would be to doubt the distinction between what is self-determined and not self-determined. "Everything that is composite, just as every becoming, demands a cause." (See supra, n. 24 and 26.)

But this extrinsic raison d'être, this realizing principle, or, in other words, this cause—where shall we seek for it? Could it be found in a subject possessing a perfection with its limit? Is Phaedo able to account for that imperfect beauty which he possesses? It is evident that Phaedo does not possess this perfection through that which constitutes him an individual, for two reasons. First, as we have already remarked, because what really constitutes him as an individual, properly belongs to him, whereas beauty is found also in other beings. Secondly, that which properly constitutes him as an individual is something indivisible, which denotes neither more nor less, whereas beauty, even in Phaedo, has degrees. "Whatever belongs to a being by its very nature, and not by reason of any cause, cannot be either partially or completely taken away."

C. Gentes, Bk. II, c. XV, § 2.


To say that Phaedo is beautiful in his own right, admitting at the same time that what properly constitutes him as an individual is something different from beauty, would be the same as saying that elements of themselves diverse are of themselves in some way one; that the unconditional union of diverse elements is possible—which would involve a denial of the principle of identity. "Whatever a thing may fittingly have, if it does not originate from its nature, accrues to it from an extrinsic cause; for what has no cause is first and immediate."

C. Gentes, Bk. II, c. XV, § 2.


What is found in a being without properly belonging to it according to its nature, is something which has been caused in it. In fact, not possessing this characteristic of itself and immediately (per se et primo), it can possess the same only in a conditional manner, by reason of another, and, in the final analysis, from another which possesses the same of itself and immediately, as something belonging to its nature ("secundum quod ipsum est"). Wherever there is diversity or composition, it is conditional, until we finally arrive at pure identity. It is only the latter that is capable of self-existence, whose existence originates from its nature, which is to being as A is to A, which is Being itself, or existence itself, ipsum esse subsistens. Every limitation of an essence would involve positing in it a duality between that which is capable of existing and existence itself. In such a case, existence could be attributed to it only as something accidental or contingent, and we should have to seek for a higher cause, continuing our search until at last we arrived at pure simplicity and pure perfection with no admixture of imperfection. Every limit imposed upon the supreme attributes of Goodness, Beauty, Knowledge, and Justice would mean the positing in them of a duality, and, therefore, of contingency. Thus the principle of identity again appears, not only as the supreme law of thought, but also as the supreme law of reality, and we have another refutation of Pantheism. The first of all beings is essentially distinct from the world, and this not only because he is essentially immutable, whereas the world is essentially changeable, but also because this being is by his very nature simple and pure, whereas the world is essentially mixed and composite. This, as we have already remarked, was the argument by which the Vatican Council refuted Pantheism. "God as being one sole, absolutely simple and immutable spiritual substance, is to he declared as really and essentially distinct from the world."

Conc. Vat., Sess. III, ch. I.


God is pure Being without any admixture of non-being. St. Augustine expressed this truth in almost the same words, both in his City of God (Bk. VIII, ch. 6) and in his treatise De Trinitate (Bk. VIII, ch. 4), and he combined the proof based on the degrees of being with the argument from motion, thus rendering his contention more striking. If a being, he says, is more or less beautiful at different moments, if its beauty varies, evidently it does not possess beauty a se. Since it advances from the less to the greater, it cannot give itself what it does not have, and so "there must be some being in which immutable, incomparable, and pure beauty resides."

This proof drawn from the degrees of being is even more convincing if we remark, with Aristotle, that the non-being which limits being is something intermediary between pure being and pure nothingness, called potency. A perfection which of itself implies no limit cannot be limited either by itself, or by any other perfection, or by pure nothingness, but only by something intermediary. Knowledge, for instance, is not limited by itself nor by another perfection, such as holiness, but by the restricted capacity of man to acquire knowledge, by our potentia for knowledge, which gradually attains to act. Similarly, existence, in which all beings participate, has various degrees, and is not limited by itself, but by the essence into which it is received, since essence denotes a capacity for receiving existence, quid capax existendi, and it is all the more perfect in proportion as it denotes a capacity less subject to restrictions, and susceptible of greater participation in the act of existence. The mineral and the plant participate in this existence, subject to the limitations of matter and extension; the animal, by the knowledge it acquires from sense perception, participates in the same in a less limited way; man transcends the limits of matter and extension, of time and space, since knowledge and desire in him, by reason of the soul, the spiritual part of his nature, may in some sense be said to be infinite; with those created beings known as pure spirits, since they are by nature pure and immaterial forms, limitation in the existence in which they participate can come only from this source; but that they are capable of existing is in them something finite; potentiality is included in the notion of their essence, an idea of limitation with regard to existence, which is their ultimate actualization. This composition, this duality, consisting of essence as limiting and of existence as limited, presupposes a cause, and, in the final analysis, a cause in which there is absolutely nothing of composition, which is not a combination of potentiality and actuality, a cause which is pure actuality, a cause which was always and in all ways self-determined, pure being to the exclusion of all non-being, and consequently infinite perfection.

See Summa Theol., Ia, q. 7, a. 1.


It is easy to see how St. Thomas was able to conclude that the First Being is not a body, since He is absolutely simple (Ia, q. 3, a. 1); that He is not composed of essence and existence, but that He is Existence itself (Ia, q. 3, a. 4); that He is not composed of genus and a difference (Ia, q. 3, a. 5); that He is sovereign goodness, absolute plenitude of being (Ia, q. 6, a. 2); that He is infinite (Ia, q. 7, a. 1); that He is supreme truth (Ia, q. 16, a. 5); that He is invisible (Ia, q. 12, a. 4), and that He is incomprehensible (Ia, q. 12, a. 8).

Let us now consider the different applications and more precise determinations of this general proof, by means of which we conclude that there is not only a First Being, but also a First Intellect, a First that is intelligible, a First that is desirable, the source of all happiness, the First and Sovereign Good, and the fundamental reason of all our obligations.

b) The first intellect. St. Thomas (Ia, q. 79, a. 4) applies the proof based on the degrees of being to the intellect and, like St. Augustine, combines it with the proof based on motion.

"We must observe," he says, "that above the intellectual soul of man, it is necessary to posit a superior intellect, from which the soul obtains the power of understanding. For what is such by participation, and what is mobile, and what is imperfect, always requires the pre-existence of something essentially such, immovable and perfect. Now, the human soul is called intellectual by reason of a participation in intellectual power, a sign of which is that it is not wholly intellectual, but only in part. Moreover, it reaches to the understanding of truth by arguing, with a certain amount of reasoning and movement. Again it has an imperfect understanding, both because it does not understand everything, and because, in those things which it does understand, it passes from potentiality to act. Therefore, there must needs be some higher intellect, by which the soul is helped to understand." And this supreme understanding must be the subsistent Intelligence, ipsum intelligere (Ia, q. 14, a. 4).


"That which participates in a perfection, that which is mobile and imperfect, necessarily depends upon that which is the essence of this perfection, upon that which is immovable and perfect. Now, the human soul participates in the intellectual life, and is intellectual only in the noblest part of its being. It attains to the knowledge of the truth only by the gradual process of reasoning. Finally, it has but an imperfect knowledge of things; it does not know everything about them; and it has a confused apprehension of things known before acquiring a distinct knowledge of them. Therefore, there must be some intellect higher than that of any human soul, which is pre-eminently intellection, and which is immovable and perfect," and which was always in possession of all knowledge as something distinct from everything knowable. (See Ia, q. 14, a. 4; q. 79, a. 4). Such an intellect is demanded to explain the origin of human understanding, manifold and imperfect as it is, and without the concurrence of this intellectual light nothing intelligible could be known by us, just as without the light of the sun there could be no such thing as the sense perception of color.

This application of the proof presents no difficulty if we recall to mind what we previously said (n. 29) concerning the understanding. It is a notion which, according to what it formally implies, does not belong to any genus. Since it is defined by reason of its relation to being, it is, like being, analogous. That is why it can be realized in various degrees, and in the highest degree can exist in a pure state, not subject to any potentiality or limitation.

Need it surprise us that the supreme intelligence is identified with being itself? By no means. If there were duality here, we should have to keep on seeking for a higher cause, until we finally arrived at pure identity.

Plotinus and Spencer raised the objection that knowledge necessarily implies a duality of subject and object. This objection in its various forms has been refuted by St. Thomas (see Ia, q. 14, a. 1-4). He commences with a consideration of man, in whom knowledge implies such a duality. Man, he remarks, is intelligent in proportion as he is immaterial, in so much as his form, which transcends matter, space, and time, enables him to know, not only this or that particular and contingent being, but being in general. And since man is not being, the intellectual faculty is in him merely a potentiality, which is in relation to being, something intentional. It is an accident of quality, and the act of understanding in human beings is merely an accidental act of this potentiality. The self-subsisting Being must also be intelligent, in proportion as He is immaterial, and since, according to the definition, He is independent not only of all material and spatial limitation, but also of every limitation on the part of essence, He is not only sovereignly intelligent, but the intellect and its act in Him are identical, that is to say, He is Being itself in the highest degree of intelligibility, always actually known, a purely intellectual and eternally subsisting light. Let us not search here for the duality of subject and object, which is the result, as St. Thomas remarks, of potentiality (or imperfection), in fact of both, "because from this only it follows that sense or intellect is distinct from the sensible or intelligible object, in that both are in potentiality" (Ia, q. 14, a. 2). Even in the act of our intellection, the intellect and its object, insofar as it is known, are identified; and Cajetan, in his Commentary on the Summa of St. Thomas (see q. 79, a. 2, no. 19), points out, as Averroes had done before him, that the intellect does not receive the object as matter receives the form, thus constituting a composite with the latter. No; the intellect becomes intentionally the known object ("fit aliud in quantum aliud": it becomes that which as such is something other than itself"). In the act of reflection, the intellect in the act of knowing is identified with the intellect knowing this of itself. That this duality still remains is due to the fact that our intellect is not of itself and always in the act of knowing and actually being known. In God there is absolute identity between the pure intellect and pure being, which is the object of the intellectual act.

We shall see that this conclusion is no less evident if we take as the basis of our argumentation not the primary intellect, but the primary intelligible. For a being to be pure act from every point of view, it must be always intelligible, not only in potentiality, but also in act; in fact, it must be always actually known (intellectum in actu). Now the intelligible always actually known is nothing else but eternal intellection.

"῎Εστιν ἡ νόησις νοἠσεως νὀησις: its thinking is a thinking on thinking." Aristotle, Met., XII, c. ix.


What has just been said is as certain as the absolute certainties of the positive sciences, for this excellent reason that the intellect perceives it immediately in being, which is its formal object. It is a fruit of purely intellectual light. This analogical attribution of intelligence to God is certain in the strictest sense of the term. The same must be said of the formal reason of existence, which is independent of its created mode (limited by the potentiality of the essence into which it is received). In like manner, the formal reason of intellection is independent of its created mode, which declares such intellection to be the accidental act of a faculty and assigns it to a category, namely, that of "quality," which is distinct from the category of "substance." In God, intellection is His very nature, that is to say, Being itself (Ia, q. 14, a. 2 and 4). This identification of being and intellection is not, therefore, due solely to the fact that a proof based upon their common traits (ex communibus) makes it a necessity (for there can be no question either of duality or of multiplicity in the Absolute), but this identity is postulated by the formal reason of each of these two perfections (ex propriis). Pure thought, of itself and always in act, must be pure being actually known; and pure being of itself and always in act from every point of view, must be the intelligible in act and intellection in act. Wherever there is a duality of subject and object, the understanding is imperfect and to a certain extent unsatisfactory. The created intellect would like to establish an immediate contact with being, without having to question itself about the validity of the representation by means of which it apprehends being. This unsatisfactoriness,

It is quite compatible with the condition of absolute certitude and merely denotes the imperfection inherent in the nature of a created intellect, especially of one which is united with a body.


which is common to every created intellect, will be dispelled only by the beatific vision, in which there will be no intermediary idea between the human intellect and the divine essence (Ia, q. 12, a. 2); this condition never existed for God, since it is in Him alone that intellect is identical with being, because in Him alone the intellect is in a pure state.

c) The first intelligible, the first truth, source of all truth. The proof for the existence of God based on the degrees of being, developed in the Ia, q. 2, a. 3 of the Summa Theologica of St. Thomas, ascends not only to a first being, but to a first truth, which is the ultimate basis of all other truths. "In beings there is found something more or less true. But more and less are predicated of different things, according as they resemble in different ways something which is the maximum. There is, therefore, something which is most true. Now, what is called maximum in any genus is the cause of all comprised in that genus." (Ia, q. 2, a. 3). Sometimes people are surprised at not finding in the writings of St. Thomas the proof for the existence of God based on the eternal verities, which was a favorite one with St. Augustine,

See Contra Academicos, Bk. III, c. xi, no. 25; De Trinitate, Bk. XV, c. xii, no. 21; De Vera Religione, c. xxx to xxxii; De Libero Arbitrio, Bk. II, c. viii, no. 20; c. ix, no. 26; c. xii, no. 24; c. xiii, no. 36. Cfr. Portalié in the Dict. de Théol. Cath., art. "Augustin."


St. Anselm, Descartes, Bossuet,

Connaissances de Dieu et de soi-même, ch. iv; Logique, I, c. xxxvi.



Traité de l’Existence de Dieu, Part II, ch. iv.


Malebranche and Leibniz.

Nouv. Essais, Bk. IV, c. ii.


Even Kant, in 1763, when he wrote his treatise on The Only Possible Foundation for the Proof of God's Existence, described the argument based on the eternal verities as the only rigorously compelling one. The possible, he said, which is given with thought itself, presupposes being, for "if nothing exists, nothing is given which may be the object of thought." He declared it to be an established fact that the Absolute, which is the ultimate basis of possible things, is unique and simple, and confirmed his proof by showing the unity and harmony which exist in the infinite world of essences or possibles, for instance, in mathematics. The proportions, the connections, the unity revealed by these ratiocinative sciences, were for him a proof that the ultimate basis of the possibles is unique and infinite, nay more, that it is an intelligence, since these harmonies are of the intelligible order.

The argument based on the eternal verities is to-day defended by many Scholastics.

Kleutgen, Philosophie Scolastique, Bk. IV, Diss., Ch. ii, a. 4; Lepidi, Elementa Philosophiae Christianae, Ontol., p. 35, Logic., p. 382; Schiffini, Princ. Phil., 1, no. 482; Hontheim, Theologia Naturalis, p. 133; De Munnynck, Praelectiones de Dei Existentia, p. 23. Sertillanges has given an admirable exposition of this proof in an article which appeared in the September number, 1904, of the Revue Thomiste, entitled, "L'Idée de Dieu et la Vérite," reproduced in the author's book, Les Sources de Notre Croyance en Dieu. It was severely criticized by the Revue Néo-Scolastique. The doctrine propounded in this article is, however, absolutely in conformity with the teaching of St. Thomas.


Its validity was formerly denied only by the Nominalists,

Cfr. Soncinas, O.P., In V Metaph., q. 30, and In IX Metaph., IV and V.


who regarded the universal as nothing but a collection of individuals. If such were the case, and all the individuals of a species disappeared, it could no longer be said that there was any real truth in the propositions formulated about their specific nature.

St. Thomas has often pointed out that, just as in the order of being and goodness, there is a certain hierarchy also in the order of truth. Contingent truths or facts are of the lowest degree; above these rank the necessary conclusions of the sciences, and in the highest place are the first principles. Moreover, St. Thomas does not hesitate to say that the necessary truths would remain as objective truths even if all contingent reality disappeared. If, for example, all human beings ceased to exist, it would still be true to say that rationality is a specific characteristic of human nature. "Remotis omnibus singularibus hominibus adhuc remaneret rationabilitas attribuibilis humanae naturae," St. Thomas says in his Quodlibeta, VIII, q. 1, art. 1, ad 1um. He repeats the statement in his answer to the third objection (ibid., ad 3um). It is worth while to read this article, in which he distinguishes human nature in three ways: (1) as it exists in individuals; (2) as it is in itself, and (3) as it is in the divine intellect.

Universals may be distinguished in four ways: (1) in se (or considered in the abstract); (2) in re or a parte rei (considered in the concrete or as individualized); (3) ante rem (as apprehended by the divine intellect before they are individualized); (4) post rem (as apprehended by the human intellect when individualized). (St. Thomas, II, d. 3, q. 2, 3, 1um; Ia, q. 85, a. 2, ad 2um; De Potentia, q. 5, a. 9, ad 16um; Quodl., 8, l. c.) It is the universal secundum se (as such), apart from the individuals in which it is found, that is here meant. Also, as Soncinas, O. P., remarked, only the Nominalists denied that necessary propositions are eternally true. Ockham made their truth dependent upon the divine liberty.


Concerning these eternal truths, which are independent of all contingent existence, the following authors may be consulted: Albert the Great, Tract. de Praedicamentis, c. ix; Capreolus, I, dist. 8, q. 1, concl. 1; II, dist. 1, q. 2, a. 3; Cajetan, De Ente et Essentia, c. iv, q. 6 (the real is of two kinds: the possible real and the actual real; the possible is not merely the thinkable, or the ens rationis); Soncinas, In Met. IX, c. iv and v; V, q. 30; Ferrariensis, Comment. in C. Gentes, Bk. II, c. 52 and 84; Soto, Dialectica Aristotelis, q. 1a, towards the end; Suarez, Disp. Met., Vol. I, p. 230; Vol. II, pp. 231, 294-298; Bannez, In Iam., q. 10, a. 3; John of St. Thomas, Logica, q. 3, a. 2; q. 25, a. 2; Goudin, Logica, p. 256. We now understand how Leibniz could have written as he did in his New Essays, Bk. IV, c. ii, and also in his Theodicy, § 184: "What the Scholastics called constantia subjecti (permanence of the subject) was very much discussed by them; what they meant by this phrase was that they could not see how a proposition formulated about a given subject can have any real truth if the subject does not exist."

Bannez, in his commentary on the First Part of the Summa Theol. of St. Thomas (q. 10, a. 3), formulated this common teaching of the Schools in three propositions, to wit: (1) The essences of things signified by those complex concepts are not eternal as to their existence (this is de fide), nor as to the essence of their being in them, because essence without existence is nothing actual. (2) That man is an animal is an eternal truth, if the word is implies that animality is an essential note of human nature; for it belongs eternally to the essence of man to be an animal. Note, however, that, with regard to creatures, this esse is not esse simpliciter, but esse secundum quid, for it is esse in potentia. (3) That man is an animal is not eternal, except in the divine intellect, if the word is refers to the truth expressed by the proposition; for truth resides in the intellect, but eternal truth resides only in the divine intellect. The few contemporary authors who refuse to accept the proof based on the eternal verities, and who claim that it is foreign to the teaching of St. Thomas, fail to see that it is according to the tenor of the third proposition of Bannez that St. Thomas speaks in his De Veritate (q. 1, a. 4, 5, 6 and Summa Theol., Ia, q. 16, a. 6, 7, 8), whereas it is in accordance with the second proposition that he writes in his Quodlibeta, (VIII, q. 1, a. 1, ad 1um and ad 3um). St. Thomas, therefore, admits the final conclusion arrived at by Bannez, that "from these conclusions it follows that the essences of things are real beings before they exist, insofar as real being is distinct from imaginary being [ens rationis, or what is merely thinkable]; but not insofar as it is distinct from actually existing being, according to Cajetan's distinction as given in De Ente et Essentia, c. iv, q. 6."

Suarez justly remarks that "certain modern theologians admit that necessary propositions are not perpetually true, but that they commence to be true when they become a reality, and cease to be true when the things cease to exist. But this opinion is in direct conflict, not only with that held by modern philosophers, but also by those of ancient times, and even by Fathers of the Church. . . ." Then follow quotations from St. Augustine and St. Anselm.

Disp. Met., Vol. II, p. 294.


The propositions: "Every being is of a determined nature," "Everything has its sufficient reason," "Man is free," "We must do what is good and avoid what is evil," unlike certain others, e. g.: "Every Frenchman has a right to vote," have always been true, from all eternity. The copula is does not denote that the two extremes are really and actually united in an existing reality, but merely that the predicate necessarily refers to the subject, regardless of whether the latter exists or not.

These truths are conditional, so far as existence is concerned, but they are absolute in the order of possibility and intelligibility, and consequently dominate the contingent realities and control the future. They state, as Leibniz remarks, "that if the subject ever does exist, it will be found to be such." (Nouv. Essais sur l'Entend., Bk. IV, ch. ii).

Only consistent Nominalists can deny this conclusion; but then they must, like the Positivists, end in rejecting the absolute necessity of the first principles of reason, as if in some unknown world there could actually be effects without a cause or realized contradictions.

Starting from this point, can we prove the existence of God? Leibniz no more doubts than does St. Augustine that "these necessary truths, being prior in existence to contingent beings, must certainly have their foundation in the existence of a necessary substance" (ibid.) and as intelligible truths must be known from all eternity. Bossuet beautifully says that "even if there were no such thing in nature as a triangle, it would still remain indisputably true that the three angles of a triangle are equal to two right angles. What we see of the nature of the triangle is certainly independent of every existing triangle. Moreover, it is not the understanding that gives truth to being; even if the understanding were destroyed, these truths would still remain immutably the same." (Logique, I, 36). Again: "If I ask myself where and in what subject these truths subsist as eternal and unchangeable, I am obliged to avow that there is a being in whom truth eternally subsists and is always known; and this being must be Truth itself and in possession of all truth." (Connaissances de Dieu et de Soi-même, IV, 5). And again: "It is to this intellectual world that Plato sends us, if we would know what is truth. If he went too far in his reasoning, if he thought from these principles that souls have innate knowledge, . . . St. Augustine has shown us how to adhere to these principles without falling into extreme and untenable views." (Logique, I, 37).

This proof is truly one a posteriori (from intelligible effects), and not a priori (like the argument of St. Anselm). It does not start from the notion of God, but from the multiplicity of rational truths arranged in ascending order, until it finally reaches the source of all truth. This proof, whatever may have been said about it, was not unknown to St. Thomas. In C. Gentes, Bk. II, c. 84, he explicitly states that "from the fact that truths known by the intellect are eternal with regard to what is thus known, one cannot conclude that the soul is eternal, but that the truths known have their foundation in something eternal. They have their foundation in that first Truth which, as the universal cause, contains within itself all truth."

St. Thomas also admits that the immortality of the soul can be proved from the knowledge we possess of the eternal truths. (See C. G., Bk. II, ch. 84). Cfr. the Commentary of Ferrariensis and Lepidi's Examen Ontologismi, p. 120.


Why did St. Thomas not develop this Augustinian argument in the article which he set aside for a special discussion of the proofs of God's existence? The reason is because this proof can be referred back to the fourth, which establishes the presence not only of a Primary Intelligence and of a Primary Being, but also of a Primary Truth (maxime verum).

In the manifold and necessary verities made known to us by reason, there is a common element, that of necessary and eternal verity, which is realized in each in varying degrees. It is found in a more perfect degree in a first principle than in a conclusion. How are we to account for this element? Manifestly it is not to be explained by the contingent realities regulated by it. Just as Phaedo has not in himself the ultimate reason for his beauty, so also he cannot be the principle of contradiction which is found realized in him as in every other being, both actual and possible. Neither can our manifold and contingent intelligences account for this common and necessary element, since it regulates all of them, instead of being regulated by them. Shall we say that the eternal verities subsist apart from one another, independently of things and of contingent intelligences? This would be a reversion to those eternal types which Plato seems to have admitted, and we have stated why the transcendentals alone are capable of realization apart from matter and individuals, and why they are identified ex propriis (that is, intrinsically) with the primary being and the primary thought. It suffices to point out here that the eternal verities cannot possess, each in itself, the ultimate reason of their necessity, since they are many and constitute a series of an ascending order; they necessarily presuppose a supreme truth, a primary ens intelligibile, which is the source of all intelligibility, the maxime verum of which St. Thomas speaks.

This maxime verum cannot be merely what is potentially intelligible; it must be of itself and always intelligible, nay, actually known by the intellect. For this reason, as we have already seen, it is identified with the primary intelligence, which is pure understanding. Hence it appears a posteriori that the primary intelligence is infinite; in fact, the laws of the intelligible order, such as, for instance, of geometrical figures, are everlasting. Moreover, the least of things contains an infinite number of details, so that we can never know all about anything. This elusive element is nevertheless intelligible in itself, and its derived intelligibility must of necessity come from an intellect that is always in action. Act always precedes potency. Revelation says the same, for we read in the prologue of St. John's Gospel that "all things were made by Him [the Divine Logos]: and without Him was made nothing that was made."

It is impossible to admit with the Pantheists that the principle of the ideal order is immanent in the world, and would have no existence apart from the concepts formed of it by the human mind. If we grant that this principle is necessary and universal, we must admit that it is independent of our intellects, which are regulated by it. The contingent, being essentially dependent upon the necessary, cannot condition the existence of the latter. To say that it does, would be the same as saying that the contingent, which is not its own cause, is the cause of the necessary, which would be absurd. Just as becoming cannot be the cause of being, so multiplicity cannot be the raison d’être of unity.

But how can all intelligibles be contained in the primary intelligible—the τὸ πρώτον νοητόν?

Aristotle, Met., XII, c. vii.


St. Thomas has explained this in his treatise on the Divine Knowledge.

See Summa Theol., Ia, q. 14, a. 1-16.


This primary intelligible is the Divine Essence itself. To know this essence adequately and exhaustively, is to know everything that it contains virtually and eminently, which means everything that can resemble it by way of analogy, that is to say, not only all actual, but also all possible, realities.

d) The primary and sovereign good, the primary object of desire. St. Thomas by the via quarta also rises to the maxime bonum, i.e., Sovereign Goodness. That which is good may be considered as simply desirable, i.e., capable of attracting our appetite, of filling a void in us, of making us truly happy, and also as that which has a right to be loved, and which imperiously compels our love, and is the basis of duty. The argument which concludes that there is a first and sovereign good, therefore, implicitly includes that by which we rise to the primary object of desire, τὸ πρώτον ὀρεκτόν of (Aristotle), the source of all happiness;

See St. Thomas, Ia, IIae, q. 2, a. 8: "Concerning happiness: Whether it Consists in a Created or in an Uncreated Good?"


and it also includes the argument by which we prove that there is a sovereign good, the foundation of all duty, τὸ ἀγαθόν καὶ τὸ ἄριστον.

See Ia, IIae, q. 91, a. 1: "Whether There is an Eternal Law?" a. 2: "Whether There is a Natural Law?" q. 93, a. 2: "Whether the Eternal Law is Known to All?" q. 94, a. 2: "What Are the Precepts of the Natural law?"


We may arrive at a knowledge of the supreme good, which is the source of perfect and unalloyed happiness, by arguing from the various kinds and degrees of goodness in created things, or else from the fact that these various kinds of goodness do not satisfy the natural desire of men.

If we start from the idea of the various kinds of finite goodness in beings, such as health, the pleasures of the body, wealth, power, glory, scientific knowledge, the joys of the mind and of the soul, we must insist upon their multiplicity and still more upon their imperfection, i.e., their limitation. Just as the multiple presupposes the one, the composite the simple, the imperfect the perfect, so we shall be led by reason to a Supreme Good, who is Goodness itself, without any admixture of non-goodness or of imperfection. This is the dialectic of the intellect.

If we start from the natural desire which finite goods cannot satisfy, then we must emphasize the restlessness which the soul experiences as long as it has not found an infinite good, or a good free from imperfection. "Restless is our heart, until it finds its rest in Thee, O Lord," said St. Augustine.

Confessions, Bk. I.


The unsatisfied soul will seek to find its contentment in goods of a higher and still higher order. This is what is known as the dialectic of love. Does the unrest resulting from this dialectic prove that there is an infinite good? Yes and no. It may engender in the mind of him who experiences it a certitude which is subjectively sufficient and objectively insufficient, like the moral faith of Kant. The exclusive method of immanence, however scientific it may be, cannot go farther than this. Objectively sufficient certitude can be had only by recognizing the ontological and transcendental validity of those first principles of reasoning known as the principles of identity, of sufficient reason, and of efficient and final causality. (Cfr. supra, n. 6).

Hence the proof may be presented in the following manner:

See St. Thomas, Summa Theol., Ia IIae, q. 2, a. 7 and 8.


Our will, which has for its object the universal good (not this or that particular good known by the senses or the conscience, but the good, according to what is implied by this term, and known as such by the intellect) cannot find its happiness in any finite good; for however perfect a finite good may be, it is infinitely inferior to that pure good which has no admixture of non-good, and which is conceived as such by the human intellect. An infinity of finite goods cannot satisfy the will, for this could never be anything but successive and potential, not an actual infinity of quality and perfection. This impossibility of finding our happiness in any finite good, thus proved a priori by St. Thomas, is also proved a posteriori, or by experience, as St. Augustine has shown in his Confessions. Therefore, the human will desires naturally (i.e., by its very nature) a pure good without admixture of non-good, just as our intellect desires absolute truth without admixture of error. Can this natural desire be vain, as if it were merely a product of the imagination?

Certain theologians

De Munnynck, for instance, in his Praelectiones de Existentia Dei.


maintain that the principle, "The desire of nature cannot be purposeless," is not certain for us except and until we have demonstrated that our nature is the work, not of chance, but of an intelligent and good God. Thus the proof based on the aspiration of the soul for the absolute good would have merely the force of a naturalistic argument, based on this induction: Throughout the vegetable and animal kingdoms we see that an object, e. g., a food, corresponds to the natural desire which calls for it; it must be the same for man, since his natural desire cannot be frustrated.

We, on the contrary, believe in the absolute validity of this proof for the existence of God. If the demonstration of God's existence were a necessary pre-requisite before we could trust the natural tendency of our faculties, we might doubt the objective validity not only of our intellect, but also of the natural desire of our will. Moreover, previous to any demonstration of the existence of God we perceive clearly that our intellect and will cannot be the work of chance, the result of a fortuitous encounter. How could a simple principle, a principle of order as well as of intellect, ever have resulted from a multiplicity without order? To say that it could would be the same as saying that the greater can proceed from the less, being from nothingness. Finally, according to Aristotle, St. Thomas, and all the great intellectualist philosophers, the principle of finality is necessary and self-evident, like the principle of sufficient reason, from which it is derived on the same grounds as the principle of causality. (See supra, n. 27). A natural desire, therefore, cannot be purposeless, for if it were, it would be without a sufficient reason, and, as we have seen, for anything to be without a sufficient reason for what it is, is a contradiction. Also, by the method of reductio ad impossibile the principle of sufficient reason resolves itself into the principle of identity. (1. Everything which exists, has its sufficient reason, necessary for it as such, without which it could not be distinguished from that which is not. 2. Everything which is, but does not exist of itself, has its sufficient reason in something else, without which it could not be distinguished from that which exists of itself). This extrinsic sufficient reason is necessarily twofold: the one is a realizing or actualizing principle, which accounts for the existence of the thing (efficient cause), while the other explains the purpose of the action and why it is performed in this way rather than in any other (final cause). The necessity of the final cause is more clearly seen in the case of an intentional being, that is to say, a being whose whole nature is a tendency towards something else. We find it to be so with the natural desire which we have been discussing. This something which is relative and imperfect necessarily tends towards something else. Just as the imperfect cannot exist except by the perfect (efficient cause), so it cannot exist except for the perfect (final cause); for the relative can exist only for the absolute. In fact, it is only the absolute which has its own sufficient reason in itself. "Potentia dicitur ad actum," i.e., a potency cannot contain its own raison d’être within itself. The natural desire for God, the natural inclination towards God, therefore, would be absurd if God did not exist; it would be an inclination tending towards something and at the same time towards nothing. It was in this sense that Hemsterhuys could say that "a single sigh of the heart for what is best and perfect is more convincing than a geometrical demonstration of the existence of God."

This demonstration does not differ from the via quarta of St. Thomas, which ascends to the primary good not only by way of exemplary and efficient causality, but also by way of final causality. This desire for God, from the very fact that it is something imperfect and limited, presupposes the perfect, just as the relative presupposes the absolute.

In presenting this proof we must bear in mind that there is question here of a natural and efficacious desire, and not of a natural desire which is inefficacious and conditional, like that which has for its object the beatific vision of the divine essence.

The Thomists

See Billuart, De Gratia, diss. 3 and 4.


distinguish two kinds of natural love, one innate, the other elicited. The former precedes all knowledge, and is identical with the natural inclination of the will; the latter follows upon the apprehension of good. This elicited love is necessary, if it results from the simple apprehension of good without deliberation; in the contrary case it is free. Moreover, it may be either absolute and efficacious, if our nature furnishes us with the means of attaining the object desired; or conditional and inefficacious, if the object desired is beyond the reach of our natural faculties.

Now, according to St. Thomas (Ia, q. 60, a. 5), every creature, each in its own way, by reason of an inborn natural inclination, loves God more than itself, that is to say, it is more strongly inclined towards the author of its nature than towards itself, just as a part is naturally more strongly drawn to the preservation of the whole than to its own preservation. Thus it is natural for the hand to expose itself in order to save the head. Moreover, every reasonable creature, with a love which is elicited and spontaneous, loves above all else the sovereign good which it seeks in all things, and which can be found only in God. By an elicited and deliberate act of natural love man can afterwards prefer God to everything else, and perceive that natural happiness is to be found only in the knowledge of God derived from His works, and in the love of God which follows this knowledge, and which implies all the natural virtues.

Finally, man can naturally conceive that it would be a good thing to know God, not only through His works, but immediately as He knows Himself. But it is beyond the scope of our nature to attain to this intuitive vision; and hence the natural desire for this object can only be conditional and inefficacious; e. g., if God were gratuitously to raise me above my natural powers, so that I could see Him as He sees Himself, this would make me supremely happy. This velleity does not enter into our proof for God's existence, for, strictly speaking, it can be frustrated, since it depends upon the free will of God to comply or not to comply with it.

See Bannez, in Iam, q. 12, a. 1.


We are concerned here with a natural desire that is absolute and efficacious. The human will, on account of its universality, which accrues to it naturally from the universality of the intellect, anteriorly to any act, cannot be satisfied with anything less than a complacent love of the principle of all good, which alone is Goodness itself. This love of the absolute above all things is also the basic principle, or at least the crown, of the great spiritual and moral systems of Plato, Aristotle, Plotinus, Descartes, Malebranche, Leibniz, and others.

We even find it in the writings of Spinoza, though in a Pantheistic form.


Immediate intuition of this Good (which is entirely a supernatural gift) is not necessary to make us love it. It is sufficient for us to know it through its works and to love it as the author of our nature. It is this Good which we love when we practice virtue and refer all our acts to it, and not to ourselves.

On this natural love of God cfr. St. Thomas, Summa Theol., Ia, q. 60, a. 5. —Concerning this proof for God's existence, cfr. Gardeil's article, "L'Action, ses Exigences et ses Resources Subjectives" in the Revue Thomiste, 1898 and 1899; also Sertillanges, Les Sources de Notre Croyance en Dieu," and our own recent works: Le Réalisme du Principe de Finalité, 1932, pp. 260-284, and La Providence et la Confiance en Dieu, pp. 50-64 (English tr., pp. 39-52).


e) The primary and sovereign good as the basic principle of duty. But the good is not only something to be desired, as capable of appealing to the appetitive part of our nature and making us happy; it is also something which must be the object of volition and has a right to be loved, nay positively demands our love and constitutes the basis of duty.

St. Thomas expresses himself very clearly on this point in his treatise on law in the Summa Theologica, Ia IIae, q. 94, a. 2: "Whether Natural Law Contains Several Precepts, or only One?" He says that there are several precepts included in the natural law, but that they all refer to the same first principle of practical reason, which is "that good must be done and evil must be avoided." This first principle of conduct, he remarks, is based upon the notion of good, just as the first principle of the speculative reason, upon which all others of the same order depend, is itself based upon the notion of being. "That which first falls under apprehension, is being, the notion of which is included in all things whatsoever that a man apprehends. Therefore, the first indemonstrable principle is that the same thing cannot be affirmed and denied at the same time; this is based on the notion of being and not-being; and on this principle all others are based, as is stated in the Fourth Book of Metaphysics. Now, as being is the First thing which falls under simple apprehension, so good is the first thing which falls under the apprehension of the practical reason, which is directed to action; for every agent acts for an end which has the aspect of good. Consequently, the first principle of practical reason is one founded on the notion of good" (q. 94, a. 2).

In truth, it is not this or that good that must be done; it is that to which our nature by its activity is essentially ordained as to its proper end. Now, common sense, like philosophical reason, distinguishes three kinds of good: (1) sensible good, or that which is merely delectable; (2) useful good, by reason of the end; (3) virtuous good. The irrational animal finds its contentment in the first kind of good, and instinctively makes use of the second without perceiving the connection between it and the end in view (non cognoscit rationem finis; Ia IIae, q. 1, a. 2). It is man alone who, because of his reason, knows the usefulness or the sufficient reason of the means employed for the end. He alone knows and can love virtuous good. This latter appears to him as good in itself, desirable in itself, and this independently of the joy experienced in its possession and of any advantage to be derived from it. Such an end is good and desirable precisely because it is in conformity with right reason and appears to be the normal perfection of man as man (qua rational and not qua animal). It is good in itself, apart from the pleasure man takes in it and the advantages derived from it, such as knowing the truth, loving it above all things, acting always according to right reason, prudently, justly, firmly, and temperately. Moreover, this virtuous or rational good appears to us as the necessary end of all our actions and, consequently, as of obligation.

St. Thomas (Ia IIae, q. 19, a. 4) explains how our natural reason is the proximate rule of our will, and how the eternal law is the supreme rule. They are related to each other, in the moral order, as the primary and secondary efficient causes in the physical order. Just as, therefore, one can ascend in the physical order from secondary causes to the primary cause, so also in the order of moral causality. As for the supreme good and the various kinds of graduated good of the rational order, these belong to the order of final causality, and postulate corresponding active principles. (Cfr. also Ia IIae, q. 87, a. 1).


Every man understands that the acts of a reasonable being must conform to right reason, just as right reason itself conforms to the absolute principles of being. Hence it is that duty is expressed by the formula that "we must do what is good, and avoid what is evil;" "Do your duty, let happen what may." Pleasure and personal interest must be subordinated to duty; the virtuous must be preferred to the delectable and the useful.

Summa Theol., Ia, q. 5, a. 6.


It is not a question here of something optional, but of something which is of obligation. In truth, it is by means of the principle of finality that reason validates its command; or, what comes to the same thing (as we have seen in n. 27), it is because of the division of being into potency and act that the will of a rational creature must tend towards virtuous or rational good, in regard to which it has a right to be called a potency, because the very raison d'être of potency is to be found in the act (potentia dicitur ad actum). Potency does not merely come to an end in the act, it is for the act, just as the imperfect is for the perfect, and the relative is for the absolute. In truth, it is only the absolute which contains its own sufficient reason in itself. A will which is by its very nature capable of willing rational good, and whose natural tendency is towards this good, cannot refuse to will it, for that would mean a complete revocation of the very purpose of its being. The will is for rational good. This good must, therefore, be realized by that which can make it a reality and which exists for that purpose. The will considered from this point of view constitutes the proximate, though not the ultimate, basis of obligation.

The common opinion of mankind and the spontaneous promptings of reason confirm the conclusions of philosophy. Starting from this point, can we construct an argument for the existence of God? St. Thomas is just as certain as St. Augustine that we can. According to him, "the natural law, and especially its first principle, is nothing else but an imprint made on us by the Divine Light, a participation in the eternal law, which is in God" (Ia IIae, q. 91, a. 2). "This eternal law is nothing else but Divine Wisdom, which directs all actions and all movements of creatures" (Ia IIae, q. 93, a. 1). "Only God and the blessed, who see Him in His Essence, know the eternal law as it is in itself. But every rational creature knows it in its reflection, which is more or less brilliant. For every knowledge of truth is a kind of reflection and a participation in the eternal law, which is the unchangeable truth, as St. Augustine says (De Vera Relig., c. XXXI." (Ia IIae, q. 93, a. 2).

Comparing this passage with Ia, q. 84, a. 5, we see that St. Thomas refuted Ontologism in advance. "Our soul," he says, "has no objective knowledge of material things in the eternal types," and it is not in the essence of God that we perceive the first principles, but the eternal types are the source of our intellectual knowledge, just as the sun is the source of our sense perception. "For the intellectual light which is in us, is nothing else but a certain participated likeness of the uncreated light, in which are contained the eternal archetypes."


If the natural moral law is a participation in the eternal law, which is in God, why can we not argue from the first to the second of these laws, and in like manner, from a consideration of the various kinds of goods which constitute the basis of our divers obligations, to the Supreme Good, which is our final end?

If we ascend by a sort of necessity from eternal truths to a supreme truth, upon which all other truths are based, why can we not ascend from the first principle of the moral law to the eternal law? We start here from practical principles, not from principles of the speculative order. The obligatory character of that which is good merely adds a new element to the demonstration, and this trait, manifested in the proximate foundation of the obligation, urges us on to seek for the absolute foundation.

As we remarked in the general proof, which includes all the others, if the virtuous good, towards which our nature is ordained, must be loved, apart from the satisfaction or advantages derived from it; if the being capable of willing it must will it, or else be purposeless; if our conscience proclaims this to be our duty, and afterwards approves or condemns without our being able to stifle remorse; if, in a word, the right of good to be loved and put into practice, dominates our activity in the moral order and that of actual and possible groups of human beings, just as the principle of identity dominates all the actual and possible realities—then there must have been from all eternity some foundation for these absolute rights of the good. For these necessary and dominant rights cannot have their raison d'être either in contingent realities dominated by them, or in those many kinds of good which, arranged in hierarchical order, are imposed a priori on human nature. These rights, since they are above everything except the Absolute Good, can have their foundation only in the latter.

If, then, the proximate foundation of moral obligation is the essential order of things, or, to be more precise, if it is the rational good for which we are by nature and by our activity essentially ordained, then the absolute foundation of this obligation must be sought for in the Sovereign Good, which is our final objective. And this obligation could not have received its formal sanction except from a law of the same order as the Sovereign Good, that is to say, it could have come only from the Divine Wisdom, whose eternal law ordains and directs all creatures to their respective ends.

Thus we rise up to the Sovereign Good (maxime bonum), not only inasmuch as it is the first to be desired, the source of all happiness, but also inasmuch as it is the first Good in itself, and the absolute foundation of all duty. And this Sovereign Good, as we have seen, is identical with the First Being, the First Intellect, which is, therefore, entitled to be called the First Lawgiver. There is correlation in the order of agencies and ends, and the ultimate end becomes identified with the First Cause, in the moral as in the physical order.

The objection is sometimes raised that this demonstration of the existence of God implies a petitio principii, Strictly speaking, we are told, there can be no moral obligation without a supreme lawgiver, and it is impossible to feel oneself bound by a categorical moral obligation, unless one is aware that a supreme lawgiver exists. Therefore, the proposed proof takes for granted what is to be proved, and merely expresses in a more explicit manner that which it implicitly assumes.

In reply we may say that it suffices to show that there is a moral obligation because of its effects, such as, for instance, the remorse of conscience, and to prove that it has its proximate foundation in the essential order of things, or, to be more precise, in rational good, towards which our nature is ordained as its general end. Thence we are led to seek for the absolutely ultimate basis of obligation—on the one hand, in the Sovereign Good which is our ultimate end, and on the other, in Divine Wisdom, which ordains all things for the Supreme Good.

Cfr. Lehu, O.P., Philosophia Maralis, 1914, p. 250. "The proximate foundation of obligation consists in the essential order of things. Although it does not act except as a secondary cause, and dependently upon the first cause, yet it is truly and properly a cause in its own order, for by its very nature it establishes the necessary connection between the human act and the ultimate end. . . . The ultimate formal end, man's own and necessary perfection, may also be said to be the proximate foundation. But the ultimate foundation is objective happiness. . . . It is God Himself who is the ultimate foundation upon which obligation rests; He is the eternal law."


There is a certain connection between this last proof, based on the moral law, and that drawn from moral sanction. We can demonstrate a priori that the Supreme Lawgiver, whose existence we have proved, must also be the Sovereign Judge, the Rewarder of good and the Avenger of evil. He owes it to Himself, as intelligent and good, to give to every being all that is necessary for it to attain the end which He has assigned to it (Ia, q. 21, a. 1), and to give to the just that knowledge of truth and that happiness which they have merited. Moreover, loving the absolutely supreme Good of necessity and above all else, He owes it to Himself to make these rights respected and to punish their violation (Ia IIae, q. 87, a. 1 and 3).

But the existence of a Supreme Judge and of an eternal sanction can also be proved a posteriori, from the insufficiency of all other sanctions. This proof is the one which, according to Kant, engenders rational faith in the existence of God—a faith with a "certitude that is subjectively sufficient, though objectively insufficient." Kant's argument is well known. The existence of God, he says, and the future life are two inseparable assumptions upon which moral obligation rests. The moral law can be expressed by the formula: Do that which can render you worthy of being happy (for virtue and happiness are necessarily connected with each other by reason of a synthetic judgment a priori). Now, God alone can realize this harmony between virtue and happiness. Therefore, God must exist. The nobler the moral character of a man is, the firmer and more lively is his faith in everything which he feels himself obliged to admit from a practically necessary point of view.

Critique of Practical Reason, Bk. II, ch. 5.


This proof would possess sufficient objective certitude if the principle that "the just man must be perfectly happy," were self-evident a priori, that is to say, for us who do not admit that there are any a priori synthetic propositions, if it were analytic.

Without inquiring into the possibility of satisfying ourselves of the evidence of this proof before we are certain of God's existence, we may rest content in seeing in this proof, based on moral sanction, an a fortiori argument for the proof from the prevailing order of the universe, which we have still to discuss. If there is order in the material world, and if this order demands an intelligent designer, then, a fortiori, there must be order in the moral world, which is far superior to the physical. Therefore, there must be ultimate harmony between the moral law, which obliges us to practise virtue, and our natural desire for happiness. The just man must some day be perfectly happy.

The proof based on the sanction of the moral law may also be presented as an a fortiori argument for that proof, based on the natural desire of the heart for the supreme good. If this natural desire postulates the existence of this good and the possibility of attaining it, at least mediately,

This means, through the mediation of created things; for the immediate possession of God cannot be other than supernatural and gratuitous.


just as the relative which is not its own sufficient reason for what it is, postulates the absolute, then, a fortiori, a deliberate and meritorious act on the part of the just man, which is something more than the natural desire common to all rational beings for happiness—must result in the possession of this (natural) happiness. This can be affirmed with a certainty which is objectively sufficient even before the existence of God has been scientifically demonstrated.


40) Proof based on the order prevailing in the world.


The fifth typical proof presented by St. Thomas is that based on the order prevailing in the world. The way for it has been prepared by the preceding proof, which concluded from the multiplicity in things to the existence of a higher unity. The present proof argues from the orderly arrangement in multiplicity to the existence of a unity of concept and an intelligent designer. We shall see that the argument can start not only from the order prevailing in the physical world, but from every being in which is found a part ordained towards another, whether it be the essence which is ordained for existence, or intelligence, which is ordained for its act (potentia dicitur ad actum). We shall thus be able to arrive at an intelligence which is its own understanding, nay, more, which is the always actually intelligible in contemplation of itself, that it is, self-subsistent Being. After a cursory exposé of this proof we shall show that it is rigorously exact in answering the objections raised against it.

The proof is presented by St. Thomas in this shape: "We see that things which lack intelligence, such as material beings, act in a manner conformable to their end, for we perceive that they always, or nearly always, act in the same way, in order to obtain the best results. Hence it is plain that they achieve their end not fortuitously, but designedly. Now, whatever lacks intelligence cannot move towards an end unless it be directed by some being endowed with intelligence, just as the arrow is directed to its mark by the archer. Therefore, there is an intelligent being which directs all natural things to their end, and this being we call God."

This can be expressed more briefly if we begin with the major, thus: "A means cannot be directed to an end except by an intelligent cause. Now, we find in nature, in the things which lack intelligence, means directed to ends. Therefore, nature is the result of an intelligent cause."

This proof, of which Kant always spoke with respect, proceeds in a perfectly natural way from the spontaneous reason, when put in contact with the world, and it is historically one of the oldest proofs for the existence of God. According to Homer, Zeus is the designer, who arranges and directs all things, (Iliad, VIII, 22; XVII, 339). Among the Greek philosophers Xenophanes says that God "directs all things by the power of the mind." Anaxagoras was the first thinker who clearly distinguished mind from matter and placed intelligence at the source and above all things, over which it presides (see Aristotle, Met., Bk. I, ch. iii). Socrates developed the proof from the final causes (Memorabilia, I, 4; IV, 3; Phaedo, 96, 199). He emphasizes the admirable disposition of the parts of the human body and the harmonious connection between means and ends. He sees in nature not only traces of intelligence, but also finds there the proof of a beneficent power, full of solicitude for men. (Mem., IV, 3). He does not say that the phenomena come into existence of necessity, but because it is good that they should. Such at least is the résumé of the discourse of Socrates as recorded by Plato (Phaedo, 96, 199). St. Thomas repeats it "Things which lack intelligence act almost always so as to obtain the best result." Plato (Phaedo, 100) declaims loudly against those who, like Democritus, sought to explain the universe by ascribing it to a material and efficient cause without intelligence. In the tenth book of the Laws he argues from the fact that God has arranged all things in the world even to the smallest detail, and draws the optimistic conclusion that God ordained all things in view of the greatest possible perfection. The problem of evil is solved by a consideration of the whole. Aristotle pointed out, and defended metaphysically the minor of this syllogism, namely, that "every agent acts for an end."

"Omne agens agit propter finem.” (Phys., 1. II, c. 3).


Regarding the major, his teaching is not so clear. According to Zeller, the God of Aristotle had no knowledge of the world. We do not think that there is anything in his text to that effect; in fact, several passages rather indicate the contrary. The controversies which have arisen on this point may be studied in Kaufmann's La Finalité dans Aristote, and in Aristoteles Metaphysik, by Eugene Rolfes (Leipsic, 1904). After the time of Aristotle the Epicureans again took up the doctrine of Democritus, whereas the Stoics developed the proof based on the final causes, insisting upon particular happenings in the universe; but they did not go farther in their reasoning than to establish the existence of a "world-soul," or an artistic fire, πύρ τεχνικόν, as they called it.

Among modern writers, Descartes, Spinoza, and, following them, the defenders of Mechanistic Evolution attacked the minor, which Leibniz defended by insisting upon the contingency of the order prevailing in the world. Kant attacked also the major, and was followed by those who, like Hartmann, are satisfied with explaining finality by an unconscious will.

We shall examine: (1) the principal objections raised against the minor, that "things which lack intelligence act for an end," and then (2) deal with the objections against the major, namely, that "things which lack intelligence cannot tend towards an end, unless they are directed by an intelligent being which knows this end."

1) The minor, as formulated by St. Thomas, concerns the intrinsic finality observable in the activity of all beings which, taken separately, lack intelligence. For instance, the eye is for seeing, and wings are for flying. Certain philosophers, e. g., the Stoics, insisted just as strongly on extrinsic finality, which subordinates things to one another. Cicero writes: "The fruits of the earth are for the animals, said the Stoics; the animals are for man, the horse to convey him, the ox for ploughing the land, and man for contemplating and imitating the universe."

De Natura Deorum, II, 14.


Descartes objected to extrinsic finality. "It is not likely," he says, "that man should be the end of creation: how many things, indeed, are in the world, or were at one time, but are now no more, without any man ever having seen them or known of them, without having been of any use to humanity!"

Lettre à Elizabeth, ed. Garnier, Bk. 3, p. 210.


Again: "It is absurd to claim that the sun, which is several times larger than the earth, has been made for no other purpose than to offer light to man, who occupies but a part thereof."

In answer to this objection we must say that final causes have been abused, and that the extrinsic finality of things often escapes us. But their intrinsic finality is a certainty, as Descartes himself recognized, saying: "In the admirable purpose assigned to each part, both in plants and animals, it is proper to admire the hand of God who made them, and by an inspection of the work, to know and praise the Author; but we cannot surmise for what purpose He created each particular thing." (Principes, I, 28). We see that the organs of the viper, as well as its actions, are ordained for its preservation and propagation (intrinsic finality); but it is more difficult to say what purpose vipers serve (extrinsic finality). We do not know; this ignorance may prove the limitations of our mind, but it does not prove that there is no final cause. The ignorance does not prevent us from affirming with certainty, that eyes are made for seeing and wings for flying, and that the swallow gathers the straw for making its nest; the word "for" is not meaningless, but points to something real, just as the word by expresses efficient causality.

But Descartes goes farther than this. He revives the Epicurean doctrine, adopted by the Evolutionists of our day, that the efficient causes explain everything. "Even though we were to believe in the existence of the chaos of the poets," he says, "it could always be proved that, thanks to the laws of nature, this confusion must gradually resolve itself into the actual order of things. The laws of nature are such, indeed, that matter must of necessity take all the forms which it is capable of receiving."

Principes, III, 37.


Judging from this passage it would seem that Descartes, like Spinoza after him, was quite ready to admit with the Epicureans and the present-day Evolutionists, not that the bird has wings for the purpose of flying, but that it flies because it has wings: that the mother has milk not for the purpose of suckling her baby, but she suckles her baby because she has milk which she wishes to get rid of. Epicurus considered living things to be the result of all sorts of combinations, some of which necessarily turn out to be harmonious. The Evolutionists (Darwin, Spencer, Haeckel and others) believe that the finality apparent in living beings can be explained by vital concurrence and natural selection. Among living beings only those survive and propagate their species which happen to be adapted to the conditions of existence. We have already seen that William James maintained that Darwinism has overthrown the proof for the existence of God drawn from final causes. "The adaptations which we find in nature," he writes, "since they are nothing else but chance successes amidst innumerable failures, suggest to us the idea of a divinity far different from that demonstrated by finalism."

Religious Experience, p. 438.


He thinks that "we ought to pay more attention than we have hitherto done, to the pluralistic or polytheistic thesis."

Ibid., p. 436.


This denial of intrinsic finality conflicts with the findings (a) of common sense, (b) of science, (c) of philosophical reason.

a) In the coordination of the parts of an organism, or of some particular organ such as the eye or the ear; in the coordination of the actions of an animal when it instinctively builds a nest, a hive, etc., common sense or spontaneous reason, which has for its object the raison d'être of things, cannot avoid seeing precisely a raison d’être which fundamentally differentiates these organisms and their activity from any aggregation of things in which the union between the parts is purely accidental. No objection will ever destroy this certainty, which arises spontaneously in, and belongs to the very essence of, our intellect. Whenever reason comes in contact with the rational, it cannot help recognizing it, and whenever our intellect discovers an intelligible element in things, it knows very well that it did not put them there. If the Evolutionist wishes to assimilate an organism to an inanimate aggregation, common sense will say with Ruskin: "The philosopher tells us that there is as much heat, or motion, or calorific energy, in a tea-kettle as in a Gier-eagle. Very good; that is so; and it is very interesting. It requires just as much heat as will boil the kettle, to take the Gier-eagle up to its nest. But we painters, acknowledging the equality and similarity of the kettle and the bird in all scientific respects, attach, for our part, our principal interest to the difference in their forms. For us, the primarily cognisable facts in the two things are, that the kettle has a spout, and the eagle a beak; the one a lid on its back, the other a pair of wings; not to speak of the distinction of volition, which the philosophers may properly call merely a form or mode of force. The kettle chooses to sit still on the hob; the eagle to recline on the air. It is the fact of the choice, not the equal degree of temperature in the fulfillment of it, which appears to us the more interesting circumstance."

Ethics of the Dust, Lect. X, "The Crystal Rest."


b) The negation of intrinsic finality is equally opposed to science. John Stuart Mill, as we have already seen, recognizes that, according to the laws of induction and the actual state of science, the most probable cause of the organic structure of the eye or of the ear, is not the "survival of the fittest," but a designing intelligence. He considers the proof for the existence of God based on finality to be an inductive argument, which in its manner of development follows closely the method of concordances. It is a "poor argument in many cases, though at times, too, it has considerable force of conviction; especially is such the case with those delicate and complicated adjustments of the plant and animal life."

Essays on Religion, p. 162.


In fact, from the mere standpoint of experimental science, the odds are overwhelmingly in favor of saying that a structure so complicated and so harmonious as the eye or the ear, could never be such without an intelligent designer, any more than the setting up of the type in the printing of the Iliad could ever be arranged again in the same way without an intelligent designer. In an organism such as the human body, the various parts are so interconnected that they are, from different points of view, causes one of the other, and concur in bringing about one complete effect. In an organic structure such as the eye, the act of seeing presupposes the simultaneous presence of thirteen conditions, and each of these conditions presupposes many others. Hartmann

Philosophie des Unbewussten, Introd., ch. ii.


has shown that, according to the law of probabilities, without any designing cause, there are 9,999,985 chances against 15 for the possibility of these thirteen conditions meeting so as to make seeing possible.

Cfr. Folghera, Hasard et Providence, p. 25; also the Revue Thomiste, 1895, p. 64.


Kant recognized the impossibility of explaining the appearance of a blade of grass by natural laws in which there is no design, but thought that an intellect which could penetrate to the very heart of nature, might perhaps explain the phenomenon without reference to design. There is nothing to this theory, as we shall see. The negation of intrinsic finality is just as much opposed to philosophic reason as it is opposed to common sense and experimental science.

c) Philosophic reason proves the insufficiency of the two explanations by which it is claimed that intrinsic finality can be discarded, and rigorously defends the principle of finality. Even if we grant that Mechanistic Evolutionism explains the survival of the fittest, it cannot explain why there should be adaptations, except by ascribing them to chance or necessity—neither of which offers a sufficient explanation.

Chance is merely the absence of an explanation for those things, of a raison d’être, of intelligibility in things. Consequently, we shall see that to try to explain everything by chance is absurd.

Marvelous things do sometimes happen by chance; thus an archer may by sheer luck hit the target; but experience shows that such cases are exceptional. Aristotle

Physics, Bk. II, ch. viii; Commentary of St. Thomas, Lect. 7-13.


has proved convincingly that reason can see in chance only something which is accidental. It is the accidental cause of an effect produced without any intention,

Hence in defining chance, Aristotle restricts himself to the order of secondary causes, and he is quite right in this; for with regard to the Supreme Intelligence there is no such thing as chance. Effects by their very nature depend upon their proximate, and not upon their ultimate, cause, as St. Thomas points out in his Commentary on Aristotle's Metaphysics, Book VI, Lect. 3.


either natural or conscious, such that it could be said to have been directly intended. The chance effect is an accidental effect which happens so as to make it seem that the action which brought it about was meant for that purpose. One digs a grave, which is the end intended, and accidentally finds a treasure. But precisely because it is accidental, chance cannot be considered the cause, in the natural order, of each agent which produces its own effect. We cannot claim that all the effects produced in nature are accidental; for the accidental necessarily presupposes what is essential. One finds a treasure in digging a grave, but it is intentionally that one digs the grave, and previous to this, the treasure was intentionally buried in the ground. Chance is but the coming together of two actions which in themselves are not fortuitous, but intentional. Aristotle says that it is accidental for a doctor to be a musician; but this accidental union presupposes two terms, which in themselves are not accidentally constituted as such. It is not an accident that a doctor is a physician, and able to take care of the sick, any more than it is accidental for a musician to be proficient in music. To seek to reduce the whole natural order to chance would mean, therefore, to reduce the essential to the accidental, and, consequently, to destroy every nature and every being; for every being has a nature which is peculiarly its own (principle of identity). All that we should have left in such a case would be fortuitous encounters, but not things capable of making such encounters, which is absurd. Two wisps of straw blown by the wind accidentally come together; but the motion of each is not accidental, for it proceeds according to determined laws of nature. Agents which encounter each other accidentally, have each his own action, and it is this action which, independently of their encounter, demands an explanation. To say, as Epicurus did, and as so many Materialists or modern Positivists have repeated after him, that chance is the cause of the natural order, is not only no explanation of anything, but an absurd hypothesis, for it is making in principle the accidental to be the basis of the natural or the essential. "Ens per accidens non potest esse causa entis per se, sed e contra essentialiter dependet ab ente per se," that is to say, accidental being cannot be the cause of substantial being, but, on the contrary, essentially depends upon substantial being.

See Aristotle, Metaph., Bk, VI, De Ente per Accidens.


But though the accidental, and particularly chance, cannot be the principle of all things, it has its place in the world. How, then, shall we distinguish fortuitous events from natural effects, which cannot be explained by chance? We recognize the latter by their constancy and by their perfection, which is revealed to us in their harmony, or, in other words, by the fact that there is unity in diversity, and the more pronounced this unity is, the more it excludes chance, which is nothing else but the accidental encounter of two causes or series of causes.

α) What happens always, or nearly always, cannot possibly be the result of chance. This constancy would be without a sufficient reason, if it were not founded on the very nature of things, which is the ultimate source of their identity.

β) It is impossible for a great number of causes to combine by chance, to produce an effect essentially one and perfect in its kind, as is the case, for instance, with the act of seeing, in which the various parts of the eye concur. If this act were the effect of chance, something essentially one would be the result of an accidental combination (ens per se ab ente per accidens produceretur), the perfect would be produced by the imperfect, order would result from the absence of order, and the greater would proceed from the less. Such being the case, the unity and perfection of the effect would be without a raison d'être, which is absurd.

γ) It cannot possibly be ascribed to chance that manifold and perfectly connected elements come from a germ of which unity is one of the essential notes, as, for instance, in the case of the oak, the various parts of which come from the acorn. Evidently chance is out of the question here, from the very simplicity of the origin, which cannot be attributed to an accidental combination of elements.

δ) A fortiori it cannot be by chance that an effect which is essentially one and perfect comes from a principle that is essentially one, as, for instance, the act of understanding comes from the intellect. Chance, being an accidental encounter of things, is evidently excluded by reason of the simplicity of the beginning and of the end of this process.

On this subject cfr. St. Thomas on the 2nd Book of the Physics, Lect. 12; alsoDe Veritate, q. 5, a. 2; C. Gentes, Bk. I, ch. xiii.


For the full development of these ideas we must emphasize the harmony prevailing in the organisms of plants and animals, or, in other words, the unity in the diversity of causes which combine and are necessary for life. We must also stress the permanence, not only in time, but also in space, of the thousands of species in the plant and animal kingdoms.

We must also insist on the instinct in animals, and note that the three characteristics just mentioned are to be found in their operations. (a) The plurality of the elements which enter into the composition of their works; (b) the harmony of the effect produced, and (c) its constancy. "We see them," says St. Thomas, "always or nearly always acting in the same manner so as to obtain the best result."

Summa Theologica, Ia, q. 2, a. 3.


The spider works very much like a weaver, the bee seems to be a perfect mathematician. (This characteristic of constancy or permanence of type, which surely is not the result of chance, shows us also, as Aristotle remarks in the second book of his Physics [ch. VIII], that the animal does not act intelligently; for it cannot, like the architect, pass judgment on the appearance of its work when completed, nor can it make any alterations in the same. If one upsets what an animal is constructing, it often, urged on by instinct, continues to work in the same way to no purpose).

Concerning these facts, see Folghera, Hasard et Providence, Paris, 1900, pp. 27 ff.; Guibert, Les Croyances Religieuses et les Sciences de la Nature, Paris, 1908, pp. 117-118; Louis Murat, L'Idée de Dieu dans les Sciences Contemporaines. Paris, 1909.


Chance, therefore, leaves everything to be explained. To wish to explain all things by it, to say that it is the cause of order in the universe, is tantamount to saying that there are effects without causes, that the greater comes from the less, the higher from the lower; that the accidental is prior to the essential, that the essential is but a name—a denial of the principle of identity—that, in consequence, the real is not intelligible. Does this mean that we deny there is such a thing as chance? Not at all. Things do sometimes happen by chance, as far as secondary causes are concerned. But to an intelligence knowing and disposing of the ensemble of causes and forces, and governing their tendencies, all the seemingly fortuitous events in life would be predetermined and foreseen.

"All things which happen in this world, as far as the first divine cause is concerned, are found to be pre-arranged and not to exist by accident; although, if we compare them with other causes, they may be found to be accidental." (St. Thomas, In Metaph., Bk. VI, Lect. 3).


But that does not mean that all these fortuitous encounters were intended as an end; they could only be the result of what is desired for its own sake, and they could not be desired for their own sake except ex consequenti. We merely affirm that to explain by chance the constant harmony of effects produced in nature, is no explanation at all, and, moreover, lands one in absurdity.

Is necessity a sufficient explanation, as Democritus and many modern Mechanists would have it? In other words, is it enough to appeal merely to the efficient cause and to the determining element it carries within itself?

We have yet to explain why this efficient cause acts, instead of remaining inert. If there is no perfection in its action, a good corresponding to the natural inclination of the agent, then this action was taken without a raison d'être. It will not do to say that this efficient cause acts because it is moved to action by another, and this in turn by still another, and so on, ad infinitum. This would be but to postpone, not to answer, the question. We want to know why it is that every efficient cause acts instead of not acting.

Moreover, the determination which bears within it the efficient cause, must also be explained, St. Thomas

De Veritate, q. 5, a. 2, ad 5um.


proposes to himself this objection: "Illud quod est de se determinatum ad unum non indiget aliquo regente; quia ad hoc regimen alicui adhibetur ne in contrarium dilabatur. Res autem per propriam naturam sunt determinatae ad unum, i.e., that which is determined to one line of action, does not need any directive agency; because a directive agency is given to anything in order to keep it from acting contrariwise. But things are determined by their very nature to one line of action." According to the Mechanists, things are constituted as follows: fire, by reason of its nature, must burn; the bird must fly; it must fly, but it has not wings for flying, In like manner, says Spinoza, the triangle, by its very nature, must have its three angles equal to two right angles; but no one will say that it possesses its peculiar nature for the purpose of having its three angles equal to two right angles.

St. Thomas answers as follows: "Ista determinatio, qua res naturalis determinatur ad unum, non est ei ex seipsa, sed ex alio; et ideo ipsa determinatio ad effectum convenientem providentiam demonstrat, ut dictum est, i.e., this determination, by which a thing in nature is determined to one line of action, belongs to it, not as coming from itself, but as coming from another; and, therefore, as has been said, this very determination for a suitable effect demonstrates that there is a providence." In other words, if you seek to explain the flight of a bird by the necessary conformation of its wings, the necessity of this conformation has still to be explained, and if it has not its own raison d’être within itself, then we must seek this raison d'être in something higher. In truth, we can explain such and such a property of a triangle by showing that it is derived from the nature of the triangle, and this fully explains it. The nature of the triangle, as geometry considers it, abstracting from all sensible matter and from all efficient causality, is something which has its own sufficient reason for what it is within itself; the triangle is of itself a triangle. The case is different with a triangular object; here we may ask why it is triangular. We have a composition (a lack of identity), which demands a cause. Likewise, we may ask ourselves: Why are the bird's wings so conformed? St. Thomas says that "this determination, by which a thing in nature is determined to one line of action, belongs to it, not as coming from itself, but as coming from another." And if in answer to this question, the Mechanists appeal to the presence of a prior efficient cause, and, in the final analysis, to a general law of physics, such as the law of the conservation of energy, they merely evade the question. We still ask, why the prior efficient cause acts, and has such and such a determination and direction, why the force operates in a certain determined manner, and why there is conservation of the same.

Descartes and Spinoza sought to reduce physics to mathematics, which latter science excludes the consideration of perceptible matter, of efficient and of final causes, and is concerned only with the formal cause. They emphatically declared that the laws of physics are absolute and necessary a priori, like the laws of mathematics, and hence denied the possibility of miracles. Spinoza held that God can no more prevent fire from burning, than He can prevent a triangle from having three angles equal to two right angles.

We fully understand that mathematics, since it considers merely quantity, should exclude the efficient cause, and consequently also the final cause, which corresponds to the efficient cause. But what right has anyone to impose mathematical abstraction upon such sciences as cosmology and metaphysics, which have for their object not only quantity, but also being, becoming, and action?

Leibniz, recurring to Aristotle, replied to Descartes and Spinoza by insisting that the order or laws of nature are contingent. He pointed out that the laws of motion and of the conservation of energy are not necessary, but could have been formulated differently. They were chosen as the most suitable, but others suggested themselves, and a choice had to be made. Is it of absolute necessity that the apparent motion of the sun should take place in a certain way, and not in reverse order? Or that there should be on earth such a vast number of animal and plant species?

Cfr. the quotations from Leibniz given by Paul Janet in Les Causes Finales, pp. 642-650.


Boutroux has defended this thesis at length in his book on the Contingency of the Laws of Nature. "The most elementary and the most general laws, both physical and chemical, express relations between things so heterogeneous that it is impossible to say whether the consequent is proportionate to the antecedent and is truly the result of this latter, as the effect is the result of a cause. . . . For us they are merely so many contacts given by experience, and, like it, contingent."

Boutroux, La Contingence des Lois de la Nature, 3rd ed., p. 74.


The law of the conservation of energy is not a necessary truth, a supreme law from which nature cannot escape. Neither is there inherent in the physico-chemical forces any intrinsic necessity compelling them to produce this particular combination which results in life, sensation, and intelligence.

On this subject see Gardeil's article in the Revue Thomiste, 1896, pp. 800, 804, 818.


Therefore, necessity is not sufficient to explain, anteriorly to the "survival of the fittest," the origin of adaptations. The necessity of physical laws is merely hypothetical; i.e., it presupposes something. And precisely what does it presuppose? Finality. The expression, "hypothetical necessity" is the English equivalent of τὸ ἐξ ὑποθέσεως ἀναγκαίον of Aristotle.

Phys., II, ch. ix.


If the end must exist, then such and such means are necessary. Thus, if a man has vision, the thirteen conditions for seeing are necessary. This necessity is not absolute, but always presupposes the means viewed in relation to the end. Then, too, there might be exceptions, as, for instance, monsters. Whereas in metaphysics and in mathematics the laws are absolute and admit of no exception, in physics they apply to the generality of cases (ὡς ἐπὶ τὸ πολύ, ut in pluribus), and the exceptions are all the more numerous, the more complicated the law is.

Finally, philosophic reasoning establishes the fact that, even if necessity existed throughout nature, and admitted of no exception, it would still presuppose finality. Let us take, for instance, a principle of operation as simple as possible, such as the force of attraction, or, better still, the intellectual faculty. There is nothing in it, no complexity of organization that needs to be explained, but there is something relative, which can be explained only by the law of finality. In fact, the principle that "every agent must act with an end in view," is derived directly from the principle of sufficient reason, just as is the principle of causality, and the principle of sufficient reason itself, as we have observed (supra, n. 24), referred back to the principle of identity, by a process of reductio ad impossibile. We have pointed out previously (n. 27), how the principle of finality is self-evident and reducible to the principle of sufficient reason. We must stress the importance of this truth.

Jouffroy, in his Cours de Droit Naturel, where he inquires into the truths upon which the moral order is based, correctly says that "the first of these truths is the principle that every being has an end or a purpose. Like the principle of causality, it has all the evidence, universality, and necessity which we find in the latter principle, and we can see no exception to either." Paul Janet, in his in other respects so remarkable book on Final Causes, fails to see that the principle of finality is necessary and self-evident, because he never discovered its exact formula, but stopped at the too general formula, "Everything has an end." He did not think it possible to affirm a priori, and before proving the existence of God, that the various Alpine slopes, for instance, have their end as well as their efficient cause. The true formula of the principle of finality is that given by Aristotle, and constantly quoted by St. Thomas: "Every agent necessarily acts for an end."

Omne agens necesse est agere propter finem." (Phys., Bk. II, ch. iii; C. Gentes, Bk. III, ch. ii; S. Th., Ia IIae, q. 1, a. 2; Ia, q. 44. a. 4)


The necessity of a final cause is declared to be an immediate necessity, not for every thing, but for every agent. The encounter of two agents, from which the mountain slopes result, may be fortuitous, but each of them must of necessity act for an end. In fact, the final cause is the raison d'être of the efficient cause. This is what Paul Janet failed to see. He also failed to realize that the principle of finality is a necessary and immediately evident principle. Ravaisson, on the other hand, was not mistaken. "We conceive it as necessary," he said, "that the cause, together with the reason for beginning, also includes the end to which a thing tends."

Rapport sur la Philosophie en France, 2nd ed., § 36.


Lachelier bases the induction just as much on the final as on the efficient cause.

See his Le Fondement de l’Induction.


Hartmann clearly explains this necessity of a final cause, by taking for an example the simplest of all cases, that of the attraction between atoms. "The attractive force of a corporeal atom," he says, "tends to approach every other atom; the result of this tendency is the production or realization of this rapprochement. Therefore, we must distinguish in force between the tendency itself, considered as a pure and simple act, and the end in view, i.e., the content or object of the tendency. . . . If the motion thus produced were not contained in the tendency, there is no reason why this latter should produce attraction rather than something else—repulsion, for instance, or why it should obey a certain law rather than some other, in the change which it undergoes during the distance traversed. . . . The tendency would not be towards any end; it would have no object, and consequently would produce no result."

La Philosophie de 1'Inconscient, Vol. II, p. 144.


This reads almost like a translation of the second chapter of Book III of the Summa contra Gentes, in which St. Thomas says: "If the agent did not tend towards some particular effect, all effects would be indifferent. But that which is indifferent toward many things, no more produces one of these than any other. Therefore, from whatever is indifferent to one thing or the other, no effect follows, except by something which is determined to produce one specific effect, because otherwise it would be impossible for it to act. Hence every agent tends to some determinate effect, which is said to be its end."

C. Gent., III, ii; cfr. Gardeil, "L'Evolutionnisme et les Principes de St. Thomas," in the Revue Thomiste, 1895, p. 581, and 1896, P. 399.


The principle that "every agency acts for an end," is self-evident, with an evidence which is not of sense perception, but of the intellect, provided that the exact meaning is given to the words: action and end, as we pointed out supra, n. 27. In fact, the end is a determined perfection which it is fitting for the agent to have as a good of its own and for the sake of which the agent acts. Now, every agent, according to the law governing its nature, produces a determined effect, which belongs to it as its perfection, and it cannot produce this effect, unless it tends towards this effect in preference to any other, and unless it is ordained towards the same.

Thus without reasoning we discover that the eye is made for seeing, the ear for hearing, the wings for flying, etc. Finality, which is a necessary raison d'être of action, applies equally to the intelligence, because this latter is a faculty of being.

The self-evident principle of finality can be defended by showing that it refers back to the principle of sufficient reason, so that to deny the former would lead to a denial of the latter. St. Thomas briefly points this out when he says that "Every agent acts for an end: otherwise one thing rather than another would not follow from the action of the agent."

Summa Theol., Ia, q. 44, a. 4.


If every agent produces, not any sort of effect indifferently, but a determinate and suitable effect, and this without tending towards this effect, without being ordained towards this effect rather than towards another; if the acorn produces the oak and not the ash, without its having a definite tendency for the one rather than for the other; if the eye sees instead of hearing, without being meant for seeing rather than hearing—it follows that the non-accidental determination and appropriateness of the effect are without a raison d’être, that determination comes from indetermination, that order arises from the lack of order, that the perfect originates from the imperfect, the greater from the less—all of which statements are absurd. The determination and the perfection of the effect could not have been realized in it, unless they were in a certain manner contained in the efficient cause. Now, for the effect not to be contained in the cause actually, but only virtually, this could not be, unless the efficient cause tended towards this effect rather than another, unless it were directed towards this effect.

Without this tendency and this order, not only are the determination and the appropriateness of the effect without a raison d’être, but even the determination and the appropriateness of the action cannot be explained. Finally, the principle itself of action or potency (active or passive) cannot be conceived except as preordained to the act. Potentia dicitur essentialiter ad actum (potency essentially refers to act) is one of the formulas pertaining to the principle of finality, which refers primarily to action and secondarily to potency, the principle of action.

In God there is no distinction between active power and action; but the action which extends to created things is directed towards an end, which is not the attainment of the Sovereign Good, which God possesses independently of others, but the manifestation of His goodness or His glory.


Potency does not end merely in the act; this latter is not simply a result of it, for in that case the act would not be predetermined and would have no raison d'être. And how could this sufficient reason be in the potency, since the act is more perfect than the potency, having more of being in itself? The act is the answer to the why of potency. It is the τὸ οὗ ἕνεκα, the id cujus gratia, the purpose of the potency, just as the imperfect is for the perfect, and the relative for the absolute. In fact, it is only the absolute which has its raison d'être within itself.

So also the act in its actual operation is for the perfection which is acquired or manifested by it. The immanent actions of knowing and of loving are ordained for the acquisition of truth and goodness. The transitive action of any agent is ordained either for the attainment of some good, or else for the communication of a good possessed by the agent, so that other beings may share in it.

Potency is for the act, and action is either for the attainment or for the communication of some perfection. The word for is not a meaningless term. Thus philosophical reason reunites with the sensus communis and justifies it.

Therefore, if there is action in the world, there is finality; for without it, this action would produce everything or nothing, but not a determined effect. For this reason we may say that the proof for the existence of God based on the finality prevailing in the world, may start not only from a consideration of the marvelous organisms or instincts of animals, but also from a consideration of any ordained multiplicity of design in things, even if it be only that which is found in every created being, whose essence is ordained for existence and whose operative power is designed for action.

The existence of the internal finality being thus affirmed and established by the sensus communis, by science and reason, there may be deduced from it the existence of external finality, as Paul Janet has demonstrated.

Les Causes Finales, p. 497.


In fact, we notice in the scale of beings that the, higher make use of the lower. Thus the mineral is utilized by the plant, which in its turn is utilized by the animal, which in turn is utilized by man. To say that the higher makes use of the lower is to say that the higher directs the lower to its own proper (intrinsic) end. Thus the animal for its own preservation utilizes the plant, which is its internal end; but this preservation is made possible only by the use of appropriate matter. Whence it follows that, corresponding to this intrinsic end, there is an extrinsic end, which is the intrinsic end of the higher being. St. Thomas says: "The end of the agent and of the patient, considered as such, is identical, but in a different way, respectively."

Summa Theol., Ia, q. 44, a. 4.


The patient, as such, not as a being, has the same end as the agent. Food is directed to nutrition, just as is the nutritive power. If the extrinsic finality of things frequently escapes our notice, and if inexperienced apologists have made too free a use of this argument, this is no reason why we should deny it. The same must be said of those cases in which there seems to be sufficient evidence of finality. Thus by means of the functioning of the chlorophyll substance in plants they purify the air by absorbing the carbonic acid in it which comes from the breathing of animals. During the hours of daylight, by means of this absorption, the plant decomposes this carbonic acid, restoring the oxygen necessary to the animal, and absorbing the carbon, with which it composes the hydrates of combustible carbon, using it to form other compounds of combustible hydrocarbons, which serve as food for the animal. But this extrinsic finality need not always be realized. It is demanded for the higher forms of life, but not for the lower. During the time when there was as yet no animal life on earth, plant life, if it existed, did not attain its extrinsic end.

It is thus that we prove the existence of finality in the world. This relation of means to an end seems even more evident in the organism or the instinctive activity of the animal, but it is also found in every agent and constitutes the connecting link between the various beings in the universe, which react mutually upon one another. The subordination of agents corresponds to the subordination of ends.

See St. Thomas, Summa Theologica, Ia IIae, q. 109, a. 6.


We can now understand why Aristotle wrote: "Everything in the universe is subject to a certain order, though this order is not the same for all beings, for fishes, birds, plants. Things are not so arranged as if each were unrelated to the other. Far from this being the case, they are all interrelated and all concur with a perfect regularity in producing a unique result. Hence the universe resembles a well arranged house."

Met., Bk. XII, c. x.


In view of what we have said, but little of consequence remains in the objections raised by the Abbé Le Roy against the minor of the proof for the existence of God from final causes.

See Revue de Mét. et de Mor., March, 1907.


This proof, according to the Abbé Le Roy, is based on extrinsic finality and is contradicted by science and critical philosophy, which admit only intrinsic finality. The principle of analogy which it establishes between our activity and that of nature, is contested by psychology. Finally, the argument regards order as something superadded, as it were by way of an afterthought, to already existing elements. We have seen that our minor is directly concerned with intrinsic finality. The affirmation of this intrinsic finality is not an anthropomorphic view, a sort of projection beyond ourselves of what we experience within the domain of our own activities, in which we find finality to be an indisputable fact. But it is quite certain that Empiricism and Subjectivistic Rationalism cannot conceive finality in any other way. In systems such as these, finality is almost inevitably a more or less gratuitous attribution to corporeal things of what we experience within ourselves. In reality, the principle of finality is not an experimental truth drawn from internal experience, but a necessary law of being, derived from the principle of sufficient reason. We do not content ourselves with asserting, as Stuart Mill does, that there is an analogy between nature and the works of human art, but we go farther and demonstrate a priori that every agent acts for an end. Finally, order is by no means to be considered as something superadded like an afterthought to already existing elements, for these elements could not exist or act without being preordained or predetermined. The end, far from being something superadded, is the first in intention of all causes (prima in intentione), even though it be the last in point of realization (ultima in executione). Before the acorn produces an oak, it is preordained for this purpose, it is made for the purpose of producing the oak.

2. Does this relation of means to end, this orderly arrangement of things, demand an intelligent cause? The major of our proof says that it does: "Beings which lack intelligence cannot tend towards an end, unless they are directed to it by an intelligent cause," or, more simply, "a means cannot be directed to an end except by an intelligent agent."

This major is often proved by saying that the end which determines the tendency and the means, is none other than the effect to be realized at some future time. But a future effect is a mere possibility, which, in order to determine its own causes, must be real and present in some way, and such a presence is possible only in a being cognizant of itself.

This argument proves that there must be a being cognizant of itself, but not that this being must be intelligent. "The animals," says St. Thomas, "have knowledge of that which constitutes the end, (for instance, they go in search of prey), and they make use of the means which will enable them to attain that end; but they do not know the nature of an end as such; they know the thing which constitutes the end, but they do not know it as an end."

Summa Theol., Ia IIae, q. 1, a. 2.


The id cujus gratia aliquid fit, that for the sake of which something is done, they do not know. They cannot perceive the relation of the means to the end; likewise, they are incapable of appropriating to themselves the means of attaining the end. Only an intelligent being can perceive this relation, because a being endowed with intelligence, instead of merely associating or juxtaposing images, perceives the reasons why things are, and the means is related to the end as such precisely because it has its raison d'être in the end. Evidently this raison d'être can be perceived only by that faculty which has for its formal object being itself, and not color, or sound, or any of the facts of internal experience. Moreover, the perception of this raison d'être presupposes that the means and the end have been reduced to the unity of a single representation, and it is only the intellectual concept that can effect such a unity. Just as we rise from the multiple to one in the proof based upon the various grades of being, so in this proof we conclude from the ordained multiplicity of things to an ordaining unity. "It belongs to reason to direct, because reason has the faculty of ordaining things to their end."

Ibid., q. 90, a. 1.


Therefore, the order prevailing in the world calls for an intelligent designer.

Kant objects that, granted the existence of finality, we cannot affirm that the proper reason of the order in the world is because it is the result of an intelligent designer. He says that it is merely an analogy; we say that it is the result of intelligent design, because we do not know any other cause.

We say that this order is the result of intelligent design, not only because chance, blind necessity, instinct, or blind freedom explain nothing, but also because order presupposes that the means find their raison d'être in the end, and because it is of the very essence of intelligence to perceive the raison d’être, which is its formal object. Moreover, intelligence is a vital and transcendental relation to being, and is, therefore, like being, analogous, and no more implies imperfection in its concept than being itself; it is an absolute perfection.

It is further objected that there could be several intelligent designers. In answer to this we would say that we observe all the forces of nature harmoniously combining for one common end, which presupposes a common purpose. Against those who admit several first principles, Aristotle remarks: "The world refuses to be governed badly. ‘The rule of many is not good; one ruler let there be.' "

Met., Bk. XII, circa finem. The quotation is from Homer's Iliad, Bk. ii, v. 204.


Moreover, these many intelligences would all have some relation to the intelligible and to being, but they would not be the being. In each of them there would be a multiplicity of design, because of its capacity for knowing and its object. We must continue our search until we arrive at a supreme intelligence, which is identified with being, and by which all the minor intelligences are definitely directed to being.

Kant insists that this proof can at most demonstrate the existence of a mighty and vast, but not of an infinite intelligence. It leads us to conceive God as the architect of the world, but not as its creator.

Cajetan had already answered this objection when he pointed out

Comment. in S. Th., Ia, q. 2, a. 3.


that it is sufficient if this proof leads us to an intelligence, without going into details, since the four preceding proofs have demonstrated the existence of a prime mover, of a first cause, of a necessary being, and of a first being that is absolutely simple and of sovereign perfection. But if we look more closely into this matter, we perceive that the intelligence claimed by this fifth proof must be pure act. If it were not so, we should have to say that its essence differed from its existence, that its intelligence was not its intellection, and that in it intellection and the intelligible were not identical.

Summa Theol., Ia, q. 54, a. 1-3.


Now, essence cannot be directed to existence, nor intelligence to the intelligible object, except by a higher intelligence which is identical with its very being, always in the act of knowing itself.

Schopenhauer admits the presence of finality in the world, but ascribes it to no other cause than an unconscious will, as an example of which he cites instinct. Bergson upholds more or less the same doctrine. It has been said in reply that this teaching substitutes zoömorphism for anthropomorphism, which brings us no farther. But to affirm that there is an intelligence is not an anthropomorphism, since intelligence, considered as such, and not merely insofar as it is human, is an absolute perfection with no trace of imperfection. If it is realized in its pure state in any being, it is not in man, but in God.

Moreover, in seeking to replace intelligence by instinct, we again encounter finality, which calls for an explanation. Finally, the cause which has produced man must be at least of equal dignity with him. To rest satisfied with an instinctive finality is to return to the hylozoism of the ancients and to endow matter with sympathies and antipathies which, far from constituting a supreme principle by which all things can be explained, need to be explained themselves. The simplest of material elements, the atom and the crystal, far from being the principle of things, cannot be explained except by some idea of a type or end, which only an intelligence could conceive and endow them with.

Hartmann recognizes that the unconscious will of Schopenhauer cannot harbor within itself any principle of determination, and acknowledges the existence of an intelligence, but describes it as unconscious. We ask: how could an unconscious intelligence know the end and meaning of finality, and how could it adapt means to that end?


Fondement de l'Induction, p. 63.


comes with an objection taken from Hegel. Let us suppose, he says, that order originates in God; now order, in a certain sense, must be prior to God's intellectual operation. Therefore, all regularly constituted order does not presuppose the operation of an intelligence. Hence, why not suppose, in accordance with the Absolute Idealism of Hegel, that nature is eternal and bears its own order within itself, that is to say, is the self-evolving idea? We should then have an unconscious finality of the logical order, which would ultimately reach the stage of consciousness in man.

It is easy to answer this objection. The order which demands a cause, is that which is in process of formation, that which is becoming, and not that which is. The order which demands a cause is that which implies an actual multiplicity of parts, and not that implied in the virtual multiplicity inherent in absolute unity. Becoming presupposes being, the multiple presupposes one, the composite presupposes the simple. All these points have been demonstrated in the preceding proofs. The order which is in God, and which has a logical priority over the divine thought, is that which is virtually implied in the very essence of God, whose perfection is infinite in its possibility of participation and whose eminent simplicity is fecund with an infinity of virtual multiplicity.

Cfr. Summa Theol., Ia, q. 14, a. 5, 6, 8, 11, 12; q. 15, a. 1 and 2.


How does this supreme indivisible concentrate within itself this multiplicity? It begins to suggest itself to those who grasp a whole science in its fundamental principles, or who succeed, as Mozart did, in hearing a melody not successively, but all at once in the very law which governed its composition. A return to the Idealistic Evolutionism of Hegel, on the contrary, is to posit a becoming which is its own reason for being what it is, and, therefore, a denial of the objective validity of the principle of identity or non-contradiction; it makes the conscious originate from the non-conscious, or, what amounts to the same thing, it makes the greater come from the less, and being evolve from nothingness.

Therefore, the proof based on final causes has lost none of its validity. Like the preceding proofs, its certainty is not merely physical, but metaphysical. It is not founded solely on the experimental or inductive method, as John Stuart Mill maintains. Its minor is based upon the necessary and self-evident principle of finality, while its major is derived from the immediate and analytic relation of the intelligence either to being or to the raison d'être of things.


41) These five typical proofs establish five attributes, which can be predicated only of the self-subsisting being, who subsists above all things.


We may now summarize the results achieved by the five typical proofs of God's existence. They establish in Him five attributes: that of First Mover, that of First Efficient Cause, that of First Necessary Being, that of First and Greatest Being (primum verum, primum intelligens, primum bonum), and, finally, that of First Intelligent Ruler.

Cajetan, Comment. in S. Theol., Ia, q. 2, a. 3.


We have already shown that each of these attributes can be predicated only of that Being whose essence is identical with its existence, and which for this reason is self-subsistent being, ipsum esse subsistens.

Summa Theol., Ia, q. 3, a. 1.


The proof for the existence of God is completed by a combination of these five ways.

The first mover must be its own activity, and being pure act in the operative order, it must be the same in the entitative order, for the mode of operation follows the mode of being. Therefore, its essence is not merely capable of existing, it is Being itself.

The first cause, to be uncaused, must contain within itself the reason for its own existence. Now, it cannot cause itself, for it would have to be in existence before it could cause itself. Therefore, it has not received existence, but is existence itself.

The necessary being implies existence as an essential predicate, that is to say, it must not only have existence, but be its very existence.

The supreme being is absolutely simple and perfect, and hence could not participate in existence, but must be self-existent.

The first intelligence, which directs all things, cannot be directed to being as to some object distinct from itself. It must be absolutely the Being always actually known to itself.

The proofs of God's existence lead up to this as their terminus, the terminus of ascending metaphysics, which rises from sensible things up to God (via inventionis), and is the starting-point in the metaphysics of the descending order, which judges everything by the ultimate reasons of things (via judicii).

St. Thomas, Summa Theol., Ia, q. 79, a. 9.


Hence we see that in this order of the ultimate reasons of things the fundamental verity is that "in God alone essence and existence are identical."

Cfr. Del Prado, De Veritate Fundamentali Philosophiae Christianae, Fribourg, Switzerland, 1911.


This is the supreme principle of the essential distinction between God and the world. That essential distinction is at once evident to us, because God is immutable, whereas the world is subject to change (1st, 2nd, and 3rd ways); because God is absolutely simple, whereas the world is composite (4th and 5th ways). It finds its definitive formula in the phrase that God is "He who is," whereas all things outside of Him are by their very nature merely capable of existing, and composed of essence and existence.

The sensus communis sees all this implicitly, though it cannot reduce it to a formula. It does not demonstrate it, but, because of its instinct for being, it feels it. It has a sort of vague intuition that the principle of identity is the supreme law of objective reality, as well as of thought, and that the supreme reality must be to being as A is to A, absolutely one and immutable, and consequently, transcendental, distinct from the universe, which is essentially manifold and changeable. We do not need to be deeply versed in Plato's Sophist or Aristotle's Metaphysics, to find out the meaning of those words which God spoke to Moses: "I am who am" (Ex. III, 14), or of St. Augustine's commentary: "In comparison with Him, the things that are mutable, are as if they were not."

De Civitate Dei, I. VIII, c. xi.


Hence, we see the meaning and the bearing of the proof for God's existence based on the universal consent of mankind. It is a confirmation of the truth. "How are we to explain this universal belief in God, if not by the persuasive force of the arguments which we have set forth? . . . If faith in the divine were the result of an unreasonable fear, or if it had been imposed upon nations by legislators for the purpose of investing their laws with a sacred authority, it would have disappeared from our midst along with the causes which gave it birth. On the contrary, this faith is everywhere maintained with a tenacity which nothing can conquer."

Vacant, Etudes sur le Concile du Vatican, Vol. I, p. 323.


Concerning this universal consensus of mankind we may say with de Quatrefages

L'Espèce Humaine, ch. 35, no. 4.


that "nowhere do we find atheism either among the inferior or the superior races; we come across it only in individuals or in schools of a more or less restricted nature." The recent discoveries in the history of religions "show that all religions acknowledge a belief in a supreme being, a creator, an organizer and master of the world, and in one who is also a father to men."

Le Roy, La Religion des Primitifs, p. 464.


A final proof of God's existence may be deduced from supernatural effects such as miracles. Every supernatural effect which can be known in a natural way, but cannot be explained except by attributing it to divine intervention, furnishes us with a proof of God's existence. Such is the case with every extraordinary event of the sensible order, which surpasses all the forces of nature, such as the resurrection of a dead man, or the multiplication of loaves, as recorded in the Gospel. This proof is not within reach of the sensus communis, which sees vaguely (though with certainty), in a miraculous occurrence such as the resurrection of a dead man, that it bears an immediate relation to being, its formal object, and to the proper cause of being as being, i.e., God. Because of this intuition, spontaneous reason refuses to be influenced by those philosophers who are opposed to the miraculous, and object that we do not know all the forces of nature. There can be no doubt about that, but when we see an effect so profound and universal that it cannot be produced except by the first and universal cause, we know that this effect is being itself.

Summa Theol., Ia, q. 45, a. 5; q. 105, a. 6, 7, 8.


By intuition the intellect spontaneously perceives a miracle to be an exceptional production of being, like creation, or an immediate modification of being as such, of what there is substantial about it. Such is the case with the multiplication of loaves and resurrection from the dead. These events presuppose an agent with immediate power over being, substance, and matter and capable of exercising this power without the intervention of any accidental modifications.

God alone possesses over the very being of things, over substance and matter, a power not only mediate (through the intervention of accidents), but also immediate. Now, the substantial reunion of the soul with the body, without the intervention of any predisposing accidental elements, presupposes this immediate power. Therefore, God alone can make this a reality. Only the Author of life can restore life to one who is dead. Natural agents cannot produce a living substance, except by way of generation, which presupposes the presence of the indispensable and accidental predisposing elements. (See Ia, q. 45, a. 5; q. 105, a. 1; q. 110, a. 2 and 4; IIIa, q. 75, a. 4; Supplement to the Summa, q. 75, a. 3).


The substantial reunion of the soul with its body can only be the effect of a cause which is capable of immediate contact with the very substance of being. Hence, to see the finger of God in a miracle, it is not necessary for us to have faith; the innate sense of being, which is natural reason or the sensus communis, is sufficient for the purpose.

As Vacant points out,

Etudes sur le Concile du Vatican, Vol. I, p. 174.


"this demonstration of the existence of God finds its corroboration when it is based upon a group of facts in which the action of a supernatural providence is manifest." The vitality and wonderful spread of the Church, its eminent sanctity, and the fact that it is an inexhaustible source of all kinds of spiritual benefits, prove that from all eternity there was a being from whom all justice, goodness, and sanctity proceeded, and who must be Goodness, Justice, and Sanctity itself.

The existence of physical and moral evil, as we have already remarked (n. 34), cannot cause us to doubt the existence of God. Moral evil, which is far more grave than physical evil, so far from disproving the existence of God, presupposes His existence, because, in the final analysis, it is nothing else but an offence against God. If evil exists, no matter of what kind it may be, God has permitted it for the purpose of manifesting His power and His goodness, for, as St. Augustine says,

Enchiridion, ch. XI.


"He would not have permitted it, if He did not have power and goodness enough to draw good even out of evil."

Such are the proofs for the existence of God. They engender a certainty which is neither moral nor physical, but metaphysical or absolute. It is absolutely certain that God exists, that the greatest Being which can be conceived, has objective reality. To deny this statement would be to deny the principle of causality, the principle of sufficient reason, and, finally, the principle of non-contradiction. The Hegelian system furnishes historic proof for this. Having set out with the avowed purpose of denying the true God, transcendental and distinct from the world, its author had to admit that contradiction is at the root of all things. The choice between God and absurdity is inexorable.


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