A Variation on the First Way of St. Thomas Aquinas

This article was first published in Faith & Reason, 8:1 (Spring 1982),  34-56. Permission to print kindly granted by Christendom Educational Corporation, Christendom College, Front Royal, Virginia, 22630.

Those who would deny the existence of God have long held that St. Thomas’ argument for the necessity of a Prime Mover is refutable on the grounds that things might, after all, be perpetually in motion by nature. This argument has been given new force by materialists who, capitalizing on the claim that entire cosmos is in some sense produced by molecular, atomic and subatomic motion, have seen the atom as a case in point for perpetual motion. In the philosophical analysis which follows, Dennis Bonnette explores the concepts necessary to understand why these claims are inadequate, and how atomic motion actually strengthens the position of Aquinas.

As is well known, St. Thomas Aquinas’ First Way to demonstrate the existence of God proceeds from motion which he describes as “…certain and evident to the senses.”(1) With respect to this proof, the purpose of the present investigation is two-fold: first, to examine the legitimacy of an objection posed against the proof in the name of the Newtonian principle of inertia, and second, to determine whether the very phenomenon which gives rise to that objection may not, in fact, serve as the basis for a somewhat novel approach to the existence of an Infinite Being.

The phenomenon of inertia has been raised as an objection against the First Way by those, such as scientific materialists, who see it as the obvious alternative to a Prime Mover: Things are in motion simply because they have always been in motion. In a challenge flung at the very heart of the First Way, John Hick suggests that:

…it remains possible that some things are just naturally–and conceivably eternally–in motion (in accordance with Newton’s first law) without being caused to move at all. Thus the possibility that the physical universe has had no initial state and consists eternally of matter in motion has to be excluded before the first Way can lead anywhere.(2)

What Hick is here talking about is Newton’s principle of inertia with respect to its description of bodies already in motion tending to remain in motion.(3) And it is precisely to avoid this objection that Jacques Maritain moves to safer ground:

Taking the principle of inertia as established, and even hypothetically granting it a meaning beyond the mere empiriological analysis of phenomena, it suffices, in order to reply to the objection, to note that, applied to movement in space, the axiom “Everything which moves is moved by another” ought then logically, by the very fact that motion is considered a state, to be understood as meaning “Every body which undergoes a change in regard to its state of rest or motion changes under the action of another thing.” And thus the axiom remains always true.(4)

When Maritain speaks of “hypothetically granting it (the principle of inertia) a meaning beyond the mere empiriological analysis of phenomena,” he seems to be hinting that his retreat is not really necessary. And it is precisely the ontological analysis of the phenomenon in question which will be the subject of discussion here.(5)

Before engaging in the promised analysis of inertia, it would be well to place the problem posed by inertia back into the context from which it arose, i.e., the question of whether the phenomenon of motion, or change, or coming to be, necessarily implies the existence of an Infinite Being as ultimate Cause of all becoming. In particular, this problem shall be considered from the perspective of the currently prevailing form of atheism itself, namely, scientific materialism. For atheism apparently recognizes the implicit logic of a world whose hallmark is becoming, and precisely to avoid the implications of new being, prefers to deny that anything really new appears in the cosmos.

Atheism evidences its assumption of the principle that from nothing nothing comes to be by the insistence of scientific materialism that the world is eternal — that there is nothing really new “under the sun.” It maintains that the “atoms” which compose the cosmos are the only real “things” or “substances” and that all that appears to come to be is simply the result of the spatial rearrangement of these submicroscopic cosmic entities.(6) Hence, it claims the phenomenon of change is largely illusory, save for the fundamental relative spatial alterations of “atoms” which alone account for all evolutionary development and “newness.”

Thus, to the modern day atomist, all that is real and comes to be in the cosmos could, in principle, be reduced to the relative motion of two submicroscopic particles in space (even if they be conceived as mathematical points). (7) At least two particles are required since the motion of one particle requires some point of spatial reference which is supplied by the other particle. Thus, in principle, the becoming of the entire cosmos can be reduced to the movement of particle A from point x to point y relative to particle B at point z. And it is precisely this motion of A from x to y relative to B at z which demands explanation — a motion which in the language of Aristotle would be described as an accidental change in the category of place.(8) (Should one deny this Parmenidean “static” characterization of ultimate units of matter, this would only serve to reinforce the following argument which is based upon the reality of change in the cosmos.)(9)

Now it is not possible to deny the reality of this constant change in spatial relation at the submicroscopic level of being. For scientific materialism has reduced the reality of all change at the macroscopic level of being — the level of things visible in ordinary experience — to an explanation in terms of the movement of submicroscopic “atoms.” If the large scale reality is to be explained in terms of submicroscopic reality, then the reality of the submicroscopic change itself cannot be denied without denial as well of the very cosmic evolutionary becoming which atheistic materialism so adamantly defends.

It is precisely at this point that the principle of inertia reappears. For when a cause of the motion of the submicroscopic entities is demanded, the first recourse of positivism is to the eternal momentum of the “atoms.” In fact, Victor Preller goes so far as to misinterpret the First Way of Aquinas in accordance with this very motion of matter in a state of eternal motion. He writes, “The first way generates a temporal regress.”(10) This curious reading of the First Way — a reading which seems to ignore Aquinas’ analogy of the staff which “…does not move except that it is moved by the hand”(ll) — is bolstered by Preller’s citing a text in which Aquinas speaks of a thrown body:

…the first mover, that is, the thrower, gives to the second mover, that is, air or water or any such body which can naturally move a thrown body, the power to move and to be moved. …[For] as soon as the first mover, that is the thrower, ceases to move, the air ceases to be moved, but it is still a mover, [italics Preller’s](12)

Of course, today no one would claim that air itself moves physical bodies. Nor is it particularly surprising that the phenomenon of inertia should have proven a bit mystifying to Aquinas at the time of his commentary on Aristotle’s Physics. Nonetheless, a correct reading of the later and more metaphysical text of the Five Ways of the Summa Theologiae reveals clearly that his intent is to describe causality which is operative hic et nunc. Not only do we possess the reference to the “staff” moved by the “hand” in the First Way, but in the Second Way Aquinas tells us explicitly that “…removing the cause removes the effect.”(13)

Even more significantly, when he treats the proof from motion in the corresponding text of the Contra Gentiles, Aquinas states, “The mover and the thing moved must exist simultaneously.”(14) Thus, there can be no doubt but that Aquinas intends, not a temporal regress, but a simultaneous regress among proper causes, in his treatment of the proof from motion.(15) What remains is to show how such an argument retains its validity when confronted by modern objections based upon the phenomenon of inertia. Specifically, what is at issue here is whether, on the one hand, the motion of a body already in a “state” of motion is actually self-explanatory according to the principle of inertia, or whether, on the other hand, such motion yet requires some extrinsic cause as its sole adequate explanation.


Consider again the paradigm described above in which the relative motion of two particles is examined — even in terms of a constant state of inertia. Note well that two diverse perspectives pertain here: (1) that of the natural scientist and (2) that of the philosopher. To the physicist, the continued motion of particles already in a state of motion is self-explanatory, a perfect instance of Newton’s first law of motion. This observation of the modern scientist correctly describes the behavior of the phenomenon in question: a body in motion tends to remain in motion. Nevertheless, precise and correct description of a given phenomenon is not quite the same thing as giving an adequate explanation of why this phenomenon occurs. This is not to challenge the validity of Newton’s insight.(16) Rather, what is being suggested here is that, just as philosophy transcends the perinoetic world of appearances (the proper domain of the natural sciences) in order to penetrate to the dianoetic realm of substantial being itself, so too, it is legitimate in this case to demand the sufficient reason in terms of being for the real and constant change which constitutes the so-called “state” of inertia.(17)

Calling motion a “state” does not render it static. Nor does it lessen the truth that such motion entails the continuous reduction of potency to act — which reduction, as Aquinas observes, requires a cause because “…nothing can be reduced (from potency) to act except by some being in act.”(18) Maritain’s alteration of “Everything which moves is moved by another,” so as to apply only to changes in states of motion or rest, is quite unnecessary. Even the constant state of motion that is described by the principle of inertia requires a continuous extrinsic cause of such motion.(19)

But what possible cause of motion can be assigned in the model considered above in which the entire cosmos has been reduced in principle to the motion of one particle relative to another? Neither particle can be the cause of the motion: particle A cannot reduce itself from potency to act and particle B is simply taken as a point of reference. Nor, as has been shown above, does the principle of inertia really add to one’s understanding of the cause. Therefore, since the entire cosmos has been reduced, in principle, to the aforementioned elements and since neither of these adequately explains the motion in question, it follows that some cause must be posited which is entirely outside the model representing the universe. It is not necessary at this point to explore the full implications of this initial analysis. But it is important to note here that recourse to the Newtonian principle of inertia will in no way avoid the need for some continuous explanation of the phenomenon of inertia in the cosmos. Moreover, this explanation, whatever it may be, must somehow transcend the universe just as the cause of motion of the particles in the model employed above transcends the particles themselves.

From the foregoing one thing is evident: the phenomenon of inertia of bodies in a state of motion is not self-explanatory. Hence, the models of the cosmos propounded by atheistic materialism which attempt to explain the becoming of the world in terms of matter in a state of eternal motion are flawed at the heart when they rest their case upon the supposedly self-explanatory character of inertia. And having redeemed the First Way from this peculiar presumption of scientific materialism, it might now be well to re-examine cosmic becoming in terms of a model which, rather than being submicroscopic as was the first, is now taken at the super-macroscopic scale of being, i.e., in this instance what shall be considered is the entire physical universe taken all at once — conceived in all the glory of its dynamic, synergistic, evolutionary character.

What is proposed now is an analysis parallel to that of Zeno’s famous paradox of the flying arrow which at a given point in time must be at rest and hence cannot begin to move again.(20) Of course, this analysis will not be based upon the Pythagorean concept of time and space as discrete units — and it should be noted that, even in the Aristotelian continuum, motion absolutely requires the continuous positing of new aspects of reality in order to explain the process of coming to be.

The illusion of motion is created upon modern motion picture film by the rapid replacement of proximate, but slightly varied, frames of stop motion images — a succession of images so rapid (24 frames per second) that the human eye records the entire process as a continuum. In the motion picture projector, the key to the rapid succession of images lies in the function of a mechanical shuttle which operates in the film sprocket holes and which actually moves the frames one after another.

What is suggested here is an analogy between this process which produces the illusion of motion and the reality of becoming which is the hallmark of the entire cosmos — especially in the view of evolutionary materialism. Now the physical world may be said to be limited in the sense that it is expressed in some definite manner at any given time and does not express those states of being which it has not yet attained. Consider, if it were possible, that the entire cosmos would be expressed or represented on but a single frame of film. In order for the continuum of time to move forward (since time is the measure of motion), some new characteristic must come to be in the world. But, whether such a change be of one aspect only or nearly infinite in complexity as the cosmos itself would surely demand, progress in motion would require “getting to the next frame” of the film. How would this be possible? Recourse to inertia has already been ruled out above.(21) And this second model makes even more clear why this is so. For the acquisition of any new “frame” of the universe requires the addition of some characteristic or quality which, in virtue of its “newness,” is lacking in the original “frame.” Since the previous state of the universe is simply, as such, lacking the qualities or aspects of being which distinguish the new state from the previous one, it cannot possibly give to itself those very qualities which are lacking to its limited mode of being.(22) Moreover, since all that which exists in the cosmos has already been included in the frame of film which represents the earlier state of the cosmos, a further obstacle to becoming presents itself in contradistinction to the process in a movie projector. For while the projector has a shuttle which moves the film from one frame to another, the cosmos does not. For the shuttle which moves the film is outside of the frames themselves, whereas in reality everything found within the cosmos has already been included in the consideration of the previous limited state of its being. There is no “external mover” to move it to the next state.

It should now become evident that the notion of a limited cosmos in a process of evolutionary becoming and yet existing solely by itself constitutes a contradiction in terms. Because it is constantly becoming, it needs to acquire new states of reality; because it is limited to its present state of being, it has no source from which to obtain those new states. What this simply means is that, without the tidy “self-explanation” of the principle of inertia, the notion of a universe in a constant state of becoming becomes utterly unintelligible — provided one restricts one’s explanation to a limited world which, because of its limitation, lacks the very qualities which must come into being in its future states.

Zeno’s famous argument against the continued motion of the arrow rested upon the discrete nature of the Pythagorean moment in time; the argument proposed herein works equally well in the Aristotelian continuum. For limitation in being does not depend upon any supposed discrete character in the process of becoming; rather it rests upon the simple fact that, for any change to occur, something new must be posited which was not contained in the earlier state from which it is distinguished as new. The new as such was not contained in the old — otherwise it would not really be new.

Once again, a physical universe in the process of becoming can be explained only provided one posits the existence of some entity which is entirely other than the universe itself whose each and every part or element is limited by the very space-time continuum in which it manifests its being and acting. Unaided material becoming is a contradiction in being.

Putting the matter at the level of immediate human experience what this all means is, for instance, that one cannot even raise his own hand all by himself. For the very fact that one’s hand is in potency to being raised is equivalent to the fact that one is lacking in the reality-state of having one’s hand actually raised. One cannot give to himself the very quality of existence which is presently lacking — precisely because it is not in his possession in order to give it to himself. The obvious recourse of scientific materialism at this juncture is to point to the tendons, muscles, nerves, and brain which are supposed to move the hand. But this is to beg the question. For, as Aquinas points out, a cause must be simultaneous with its effect.(23) And as long as the hand is not yet actually raised, it is not raised precisely because these various moving factors are not themselves as yet fully in act, or else, the hand would already be raised. For, how can they begin to move when each of them considered in itself is also lacking in that state of actuality which would constitute its own contribution to the raising of the hand in question?

The common objection that, after all, we possess the “power” to move our limbs ignores the fact that “power” is but another name for the potency to do something and that potency as such is not act. Potency is on the side of non-being — what is able to be, but is not. The negative character of potency is clearly manifested when one ponders the uncharitable implication of suggesting that someone is “potentially quite intelligent.” Potency bespeaks what is not, not what is. The act of having one’s hand raised is precisely what is lacking to someone with his hand not raised — and all the potency in the world cannot supply for that act which is not actually present. Nor, for that matter, can any other material agent assist in the act of elevation here required unless it too gains some quality of existence which it is presently lacking. This amounts to saying that for someone else to come and raise the subject’s hand presupposes that the would-be assistant can himself overcome the same impediment to the raising of his hand — for he must raise his own hand in order to raise the hand of the subject.

Note well that what was stated above was simply that one could not raise his own hand all by himself. It was not denied that hands can be raised and frequently are. What is being denied here is that beings which lack a certain state of perfection can give that perfection to themselves. And whether one considers but one single man trying to raise his hand or the entire cosmos in a state of inertial becoming, the inference is the same: things limited to their present state of actuality cannot all by themselves account for their acquisition of new states of actuality. Something else must be posited, i.e., something which already possesses that actuality which is lacking to the unraised hand or even to the present state of the universe taken as a whole. And that something must be other than the previously considered finite components of the analysis.(24)

In light of the foregoing, certain inferences may be drawn — inferences which will move the plane of this investigation from the merely cosmological to the properly metaphysical. First, it is now evident that a purely physical universe in which motion exists — nay, in which motion is of the very definition of its nature(25) — is an entity which cannot be explained in terms of itself alone. Something else must be posited: something non-physical. Second, this non-physical entity (or entities) must constitute the ultimate explanation of all that which comes to be in the physical world, since the entire cosmos is lacking in those new qualities which arise through motion, and therefore, neither can one finite part of the cosmos adequately account for its own motion nor can one finite part adequately account for motion of yet another finite part. Third, the role played by this non-physical entity (or entities) is that of source of all that which comes to be: such being stands as cause to the effect produced. In a word, the eternal evolution of the cosmos assumed by atheistic materialism in order to avoid the existence of some transcendent spiritual cause necessarily implies just such a cause — not, at this point, necessarily a cause of the very being of the world, but certainly a cause of that being which comes to be — even if it be only the accidental being of the rearrangement of particles in space as claimed by modern atomists.

One further observation: this spiritual source itself stands entirely outside of time as well as space — for if it were subject to the form of becoming which is time, the same logic employed above would render it incapable of accounting for its own progress through time and the coming to be entailed therein.

One might well wonder at this point whether the entire above analysis may not encounter a fate which some suggest was encountered by Aristotle in his analysis of motion. That is, having discovered his first unmoved mover in Book VIII of his Physics,(26) he then seems unsure as to the exact number of these prime movers and even raises the question as to whether 47 or 55 of them may exist in Book XII of his Metaphysics!(27) How can the exact number of these spiritual causes of motion be determined? A closer examination of the nature of such a spiritual source as would be required to explain all motion may remedy this perplexity.


What is now evident is the need for an adequate source for all the new qualities of existence which are manifested among all finite beings which actually undergo change. The term “source” is used here with deliberate ambiguity because the question of the number of possible agents involved has, as yet, to be determined. What has been determined is that no physical agent can serve in this role.

That such a source must exist follows from the fact of motion in the physical world — a fact which is, as Aquinas points out, “…certain and evident to the senses.”(28) Moreover, since this very investigation has revealed the existence of at least one spiritual agent of change, the suggestion made by Garrigou-Lagrange that motion also may occur in the spiritual domain must be taken into consideration.(29) A spiritual source of any such spiritual motion must also be granted.

When one attends closely to the effect produced by the source of all becoming it becomes clear that such agency actually requires a form of causality which is appropriate to but a single Infinite Being alone. This follows from the fact that the adequate source of coming to be cannot be any finite agent since every finite agent is limited by its form with respect to that which it can cause.(30) And since limited beings, while they may function as secondary causes of that which comes to be in change, do not express all possible existence within their natures, they cannot function as the ultimate source of all new expressions of existence in a real world which is constantly coming to be. This argument will be redeveloped below with greater critical precision.

It is not denied here that limited beings — both spiritual and physical — are true causes of that which comes to be in change. Indeed, as Etienne Gilson has eloquently argued, the real causality of secondary causes is essential for adequate recognition of the infinite perfection of the First Cause.(31) Nonetheless, regardless of the number and function of secondary causes, it is evident from the foregoing that one or more agents must exist which cause the coming to be of new qualities of existence in those things which change. But that secondary causes should act all by themselves is not possible precisely because they are secondary causes. The question remains as to whether more than one being can act as the source for new qualities of existence which are manifest in reality — regardless of whether secondary causes operate or not.

A proper metaphysical analysis reveals that only one being can serve as the universal source of all new qualities of existence which appear among finite changing realities. The key to this is the recognition of the truth that to cause “new qualities of existence” is really to cause “new existence” — even if the only “newness” accorded to the finite order should be the change of relative spatial position of subatomic particles typically granted by scientific materialism or reductionism. This is so because even a mere accidental change of position in space and time constitutes a real change in the way in which a thing exists.

But it might be objected that while “new existence” is manifested by an entire new substance coming into existence, the materialist’s sole concession refers merely to an accidental alteration whose coming to be does not touch a thing’s substantial existence. Even Aquinas, following Aristotle, claims that substance alone is true being and that accidents are called beings only insofar as, through them, some substance exists in a certain manner with a certain quality.(32) For example, as Aquinas says, “…whiteness is called a being because by it something is white.”(33) Indeed, accidents are not even accorded the dignity of being said to possess “esse”–but only “inesse.”(34)

The preceding objection derives its force from an implicit denigration of accidental coming to be. While the reality of substantial existence is granted by this objection, new accidental existence is not seen as being “really real,” or, if new is real, it is not perceived as requiring the same sort of explanation which new substantial existence would entail.

An adequate response to this objection will require a disjunctive analysis of the problem posed. This is because the question of whether or not accidents may be said to possess their own real existence has been the subject of some controversy in recent decades among the followers of Aquinas themselves. Rather than attempt a definitive demonstration in terms of but one side of this dispute (which might thereby fail to convince adherents of the opposite side), this article will attempt a simultaneous solution which argues from both sides of the question — so as to demonstrate its point to adherents of either position.

On the one side is found a doctrine which more or less dominated Thomistic circles some two decades ago and which insists that accidents actually possess no existence of their own, but rather simply share in the existence of the substance in which they inhere.(35) Further, substance is not conceived as the sort of “static substrate” depicted by John Dewey in his Reconstruction in Philosophy.(36) Rather, the acquisition of a new accidental form by a substance is seen to constitute a real change in the very substance itself. The reason for this is that act is always proportioned to its corresponding potency.(37) Hence, any alteration of an act necessitates a corresponding alteration of that potential principle which receives and limits it. But accidental form is to substance as act is to potency. From this it follows that any change in the accidents which actually modify a substance must entail a corresponding change in the substance itself. From this viewpoint it is an oversimplification to employ the conventional formulation that accidents change while substance remains the same in accidental change. Rather, the composite structure of accidents and substance undergo the accidental change. Further, since there is but one act of existence in the substance and since accidental change is now seen to entail a change of the substance itself, it follows that accidental change entails that new substantial existence comes to be in the substance itself. This, of course, would require an adequate cause for new substantial existence (esse)– something whose nature could account for its coming to be. In this doctrine such “mere accidental change” would indeed “touch a thing’s substantial existence.”

On the other side of this controversy is a position which has gained greater adherence in more recent years. It insists that accidents do, indeed, possess their own existence (esse) — and do so in extramental distinction from the substance in which they inhere.(38) This somewhat more complex expression of the accident-substance relationship is summarized by Barry Brown as follows:

Although accidental being is really “other,” it is however, radically dependent. The succession of accidents upon their subject is a sequence permeated by efficient causality. …For the substantial esse is now revealed not only as the intrinsic actuation of the substantial essence, but also as the active principle of actualities other than itself: the thing’s multiple and complicated accidental being.(39)

By insisting that substantial esse is distinct from, but an efficient cause of, accidental esse, Brown expresses a doctrine on which accidental coming to be clearly constitutes the coming to be of “new existence” — new esse in the accidental order of being. And yet, by claiming that substantial existence is the cause of accidental existence, Brown makes it clear that it is not the coming to be of new existence of which he speaks. For if a substance could account for the coming to be of its own new accidental existence, it would reduce itself from potency to act, which has been ruled out earlier. While a per se accident, or property, may indeed flow from a thing’s substance, it is precisely not new in so doing, since its existence must commence at the same time as that of the substance to which it belongs. And while a contingent accident may be sustained in existence by its substance after the accident comes to be, in its very coming to be it is necessarily dependent upon some extrinsic cause, as seen above. In any case, this latter position accords to accidental change the actual coming to be of new existence in the accidental order. (Hence, the former position admits the reality of new substantial existence, while the latter admits the reality of new accidental existence.)

Now the meaning of these two types of existence—accidental and substantial—as well as the distinction which obtains between them is clarified by Gerald Phelan as follows:

Since the act of existence (esse) is always proportionate to the “whatness” of the ens of which it is the act (whether that ens be a substance or not—albedo est ens, In I Sent., d. 8, 1, 3), it is understandable that the distinctions which render various entia other than one another (real distinctions in the case of differences and diversities; distinctions of reason in the case of diverse modes of signifying) would be transferred to the “othernesses” between the acts of existence (esse) themselves.(40)

That is to say, since form is to existence as potency is to act, the extramental distinction between accidental form and substantial form requires that their acts of existence be diverse. Now it is central to this analysis of the two diverse doctrines described above to observe that while existence (esse) may be diverse with respect to the various substantial or accidental forms which it actualizes, such diversity arises only with respect to the corresponding potential principles which it actualizes — not with respect to existence considered in itself or absolutely. For existence as such transcends the ten categories of being: substance and the nine accidents,(41) Existence is analogically expressed in both substance and accidents.(42) Hence, new existence, whether substantial or accidental, absolutely requires some cause capable of producing existence as such. Whether the existence which is new be substantial or accidental in nature is, thus, irrelevant to this inquiry. What is relevant is that, according to either doctrine described above, the very nature of an evolving, dynamic cosmos — even if it be conceived as nothing but the coming to be of new accidental states constituted by “atoms” in motion — necessarily entails the constant emergence of new existence which, considered as such, demands an adequate causal explanation.

But a being acts or causes in accordance with its form which limits its mode of existence and acting.(43) The question at hand is whether any being whose nature, essence, or form fails to include or be identified with existence as such can adequately explain the coming to be of new modes of existence. Viewed from the standpoint of “qualities” taken simply in their formal character, it would seem quite possible that some limited being could communicate those qualities which it possesses to other beings. But insofar as the giving of qualities necessarily entails the giving of the existence of those qualities as well, any causality requires the existence of some cause which can actually give the act of existence itself— even if that act be only in the accidental order of existence.

Now no being can lack that which belongs to its very nature, just as a triangle cannot exist without one of its three sides.(44) Hence, existence as such cannot belong to the very nature of any limited being since existence is partially removed from that nature. Only one being can, properly speaking, cause new existence. And that must be a being whose very nature is existence itself. The reason for this is simply that a being can only cause something which is of its own nature — unless that something which it transmits comes from without by reason of an extrinsic cause.(45) But existence as such cannot be of the very nature of any limited being, since by its very limitation in being existence is removed from that thing in some respect. But if every being were lacking in existence of its own nature, then existence would belong, as such, to no existing nature. Now even an infinite multitude of those things whose natures are lacking a certain quality cannot supply that which is lacking — just as an infinite multitude of idiots would never constitute one intelligent man.(46) Therefore some being must exist which possesses existence of its very nature and which, because of this fact, possesses existence without any limitation, i.e., it is an infinite being.(47)

Since something would have to distinguish two such infinite beings from one another, one would have to possess some quality of existence which the other did not. Hence, both could not be infinite. Thus only one such infinite being can exist(48) — and this fulfills the nominal definition of God. Thus the phenomenon of inertia has been seen to require the existence of a transcendent cause of all coming to be, a single Universal Donor of all new existence in the created world. The Prime Mover is a true Creator of new existence — whether it be substantial or accidental. The major focus of this analysis has been God as observed through His activities in creating new accidental existence in the cosmos.


Because the foregoing analysis might raise certain objections insofar as it insists that to cause new existence even in the accidental order requires the creative causality of God alone, it would seem appropriate to consider a few texts in Aquinas which reveal such an analysis to be consistent with his metaphysics. First, consider Aquinas’ very definition of a cause. He writes, “…the name Cause implies a certain influence on the existence of the thing caused.”(49) Moreover, he explicitly recognizes that even causes of accidental existence are such by the power of God alone:

From this however it is clear that God is the cause of all things which operate inasmuch as they operate. For every operator is in some way a cause of being, either of substantial or accidental existence, (italics mine) But nothing is a cause of being except insofar as it acts by divine power as was shown. Therefore every operator operates through the power of God.(50)

In the above cited text Aquinas refers back to the preceding chapter of Book III of the Contra Gentiles in which he explains that the existence of all things is the proper effect of God alone, since “…in God alone is existence its own essence.”

God alone however is being through His own essence, whereas all other things are beings through participation; for in God alone is existence its own essence. Thus, the existence of every existent is the proper effect of Him. And further, everything which puts something into existence does this insofar as it acts by the power of God.(51)

It is evident that the earlier cited text is but a more specific expression of this text — with the later text extending the need for God’s power even to include the production of accidental existence, such as would occur even in the relative spatial movement of subatomic particles. That Aquinas could well concur with Newton in extending God’s creative act to the conservation of the accidental activity manifested by bodies moving in a “state” of inertia is clear from the following:

However, just as God not only has given existence to things when first they began to be, but also so long as they exist He causes existence in them, conserving things in existence, as has been shown, so also He has not only given operative powers to them when [those] things were first made, but He always causes [such powers] in things. Whence, should this divine influence cease, every operation would cease. Therefore, every operation of a thing is reduced to Him as to [its] cause. (52)

From the foregoing analysis of the phenomenon of inertia, it should be evident that God alone is the Supreme Agent who conserves the existential obedience of all natural bodies to His law. It is a mandate of the Divine Will and as Aquinas puts it, “…should this divine influence cease, every operation would cease.” This is not to say that Aquinas explicitly reckoned with the “puzzling” phenomenon of inertia in accordance with the above analysis. Rather, it is to say that inertia is an instance of motion which manifests new existence in a manner which would require the existence of God as its sole adequate explanation according to the above cosmological and metaphysical analysis — and that the foregoing analysis is consonant with the general principles of Aquinas. The more precise understanding of inertia which post-Newtonian insights have afforded permits more cogent application of Aquinas’ physical and metaphysical principles in the present inquiry than was, perhaps, possible in the mediaeval cosmology.

Finally, it should now be evident that the attempt of atheistic materialism or reductionism to explain the cosmos in terms of atomic matter in a state of perpetual evolution backfires upon its own presumptions. For, to the simple question, “Why new existence?,” it can give no reply. If it denies new existence in the universe, then it denies the very progress and becoming which evolutionary materialism trumpets. And if it admits the reality of newness in the universe — even at the level of subatomic accidental change — it finds itself at a total loss to explain its source: for within a purely finite cosmos there is no adequate explanation. Why new existence?(53) Only because there exists a Pure Act of Existence who, in His unchanging unicity, precontains in supereminent fashion all the limited perfections which are successively unfolded in the ongoing creation which is our ever-changing world. In a word, atheistic materialism implicitly presupposes theism.


  1. Certum est enim el sensu constat aliqua moveri in hoc mundo. S.T.,I\, q. 2, a. 3; Ottawa cd. Unless otherwise designated, all English translations in this article are my own.
  2. John Hick, Arguments For the Existence of God (New York: Herder and Herder, 1971) p. 40.
  3. See Isaac Newton, Optics, 111, 1, in Great Books of the Western World (Chicago-London-Toronto: Encyclopaedia Britannica, 1952) vol. 34, p. 540.
  4. Jacques Maritain, Approaches to God (New York: The Macmillan Company, 1967) p. 39.
  5. I have already touched on this problem elsewhere. See Dennis Bonnette, Aquinas’ Proofs for God’s Existence (The Hague: Martinus-Nijhoff, 1972) pp. 99-104.
  6. For a splendid example of this sort of effort by scientific materialism to explain the origin and development of the universe without recourse to a Supreme Being, see Hans Reichenbach, The Rise of Scientific Philosophy (Berkeley and Los Angeles: University of California Press, 1951) pp. 206-214.
  7. The term “atom” suffers an essential ambiguity. In its original Greek meaning, atoms were conceived as ultimate, indivisible, minute particles. The smug assumptions of nineteenth century reductionism which conceived the 92 elements of the periodic table as “atoms” in this Greek sense were forever shattered by the twentieth century discoveries of subatomic physics. Ever newer theories continue to emerge. Yet, whether the building units of physical reality be conceived as homogeneous material masses, centers of force, pure energy, particles, waves, or whatever, what is essential to our analysis is that they come to be either in themselves or in relation to one another. As long as change is present at the subatomic level, something new comes to be and the argument can proceed. For an analysis of various meristic theories, see Brother Benignus (Gerrity, Nature, Knowledge, and God (Milwaukee: The Bruce Publishing Company, 1947) pp. 112-114. See also, Reichenbach. op. cit., ch. 11, “Are There Atoms?,” pp. 166-190; William A. Wallace, From A Realist Point of View (Washington, D.C.: University Press of America, 1979), Essay IX, “Are Elementary Particles Real?,” pp. 187-199.
  8. See Aristotle Physics, IV, 4, 212a7-212al9; Meta., XI, 12, 1068M5-1069al5.
  9. The ultimate dynamic position is that of “process philosophy” which identifies being with becoming. For the most devastative critique of this anti-intellectual position ever written, see Reginald Garrigou-Lagrange, God: His Existence and His Nature, trans. Dom Bede Rose (St. Louis: B, Herder Book Co., 1939) pp. 164-181. See also, Joseph Dieska, “Teilhard de Chardin or Thomas Aquinas?,” Social Justice Review, March, 1967, Section #2, pp. 440-444; Joseph Dieska, “Philosophy in Catholic Higher Education,” Social Justice Review, October, 1967, p. 187.
  10. Victor Preller, Divine Science and the Science of God: A Reformulation of Thomas Aquinas (Princeton, N.J.: Princeton University Press, 1967) p. 114.
  11. …sicut baculus non movet nisi per hoc quod est motus a manu.” S.T., I, q. 2, a. 3; Ottawa ed.
  12. The English text here is taken from Preller, op. cit. p. 113, “…primum movens, scilicet pruiiciens, del secundo moventi. scilicet aeri vel aquae vel cuicumque tali corpori quod est natum movere corpus proiectum, ut possit movere et ut possit moveri:…statim cum primum movens, idest proiiciens, cessaverit moveri, et aer cessat moveri, sed adhuc movet. In VIII Phys., 22. n. 3; Marietti ed.
  13. …remota autem causa, removetur effectus. S.T., I, q. 2, a. 3; Ottawa ed.; also, the corresponding Way of the Contra Gentiles reads, “…removing a cause, however, is to remove that of which it is a cause.” C.G., I, 13, #33.
  14. Movens et motum oportet esse simul…. C.G., I, 13; Leonine ed.
  15. See Bonnette, op. cit., pp. 75-79.
  16. As a matter of fact, according to Wallace, who cites several authorities to support his view, Newton himself did not propose his physical laws as absolute in themselves, but rather as being themselves a manifestation of the divine causality. See Wallace, op. cit., pp. 348-349.
  17. For an explanation of the distinction between perinoetic and dianoetic intellection, see Jacques Maritain, The Degrees of Knowledge (New York: Charles Scribner’s Sons, 1959) pp. 202-218.
  18. …non potest aliquid reduci in actum nisi per aliquod ens in actu…. S.T., I, q. 2, a. 3; Ottawa ed.
  19. Newton himself is in explicit agreement with this philosophical conclusion. In his Optics, he writes, “The vis inertiae is a passive principle by which bodies persist in their motion or rest, receive motion in proportion to the force impressing it, and resist as much as they are resisted. By this principle alone there could never be any motion in the world. Some other principle was necessary for putting bodies into motion; and now they arc in motion, some other principle is necessary for conserving the motion.” Newton, loc. cit. Wallace writes, “The first law of motion and the concept of inertia that it involves state only partial truths. They are not verified of an entire physical reality, but rather abstract from efficient causality and its relation to compulsory motion. …looking at the truth contained in the first law from the vantage point we have now attained, it can be seen that the former attains its full stature and most intelligent justification when understood as requiring the continued application of an extrinsic mover. …Although it is not known to modern physicists, moreover, it was known to Newton, the father of their science, who knew better than they the limitations of the principles he first formulated.” Wallace, op. cit., pp. 363-364.
  20. See Zeno’s argument as given in Aristotle’s Physics, VI, 9, 239b5-239b32. See also, Wesley C. Salmon, Space. Time, and Motion (Minneapolis: University of Minnesota Press, 1980) pp. 33-34. For a brief resume of Pythagorean pluralism and of Zeno’s dialectical attacks upon it, see Frederick Copleston, A History of Philosophy (Westminister, Md.: The Newman Press, 1957) vol. I, Greece and Rome, pp. 29-37, 54-60.

  1. See Section #2 above. As was pointed out, the principle of inertia merely describes the tendency of a body in motion to remain in motion; it does not explain adequately how it is possible for the continuous manifestation of new aspects of being which motion constitutes to take place. See Etienne Gilson. The Elements of Christian Philosophy (New York and Toronto: The New American Library, 1960) pp. 72-73.
  2. See S.T., I, q. 75 a. 1, ob. 1. Indeed, nothing can give to another what it does not itself actually possess — nor can it give it to itself, for the same reasons Aquinas offers to prove that nothing can reduce itself from potency to act. See C.G., I, 13, #9.
  3. “…removing the cause removes the effect.” S.T., I, q. 2, a. 3; Ottawa ed. See note 13 above.
  4. “…and as the lowest agent is found to be immediately active, thus the power of the first agent is found to be immediate to the producing of the effect. For the power of the lowest agent is not that it produced this effect of itself (ex se), but from the power of the proximate superior (agent), and it has this power by the power of a (yet) superior (agent), and thus the power of the supreme agent is found productive of the effects of itself, as if it were the immediate cause, as is evident in the principles of demonstration, of which the first is immediate.” C.G., III, 70. Leonine ed.
  5. See Aristotle, Physics, I, 2, 185al3-15.
  6. See Aristotle, Physics, VIII, 5-10, 258b4-267b26.
  7. See Aristotle, Metaphysics. XII, 8, 1073al2-1074bl4. Note that Aristotle’s criticism of the anthropomorphic character of pagan dieties belies any suggestion that he was defending polytheism merely to protect his personal welfare in a polytheistic state. See also, Aristotle, Physics, VIII, 6, 258bll, 259a6-13, 259b28-31; Copleston, ibid., pp. 315-316.
  8. S.T., I, q. 2, a. 3. See note 1 above.
  1. See Garrigou-Lagrange, op. cit., p. 262. That Aquinas does hold that spiritual motion exists is evident, as in the case of the will. See S.T., l-II, q. 9. a. 4.
  2. Aquinas makes clear the role of form in determining an agent’s ability to cause when he writes that “…the form, which is the first act, is for the sake of its operation, which is the second act.” “…ita forma, quae est actus primus, est propter suam operationem, quae est actus secundus… S.T., I, q. 105, a. 5; Ottawa ed.
  3. “A universe without genuine causality, or with a causality not allowed its full effect, would be a universe unworthy of God.” Etienne Gilson, The Spirit of Mediaeval Philosophy (New York: Charles Scribner’s Sons. 1940) p. 145. See also, C.G., III, 69.
  4. “That however is properly said to be which itself has existence (esse), subsisting, as it were, in its own existence (esse). Whence, substances alone are properly and truly called beings. An accident, in truth, does not have existence (esse), but by it something exists, and for this reason it is called a being — as whiteness is called a being because by it something is white.” S.T., I, q. 90, a. 2; Ottawa ed. See also, In VII Meta., 1, nn. 1248-1258; In XII Meta., l, nn. 2419, 2420-2422.
  5. Ibid.
  6. Aquinas writes, “…accidentis enim esse est inesse. S.T., I, q. 28, a. 2; Ottawa ed. See also, De Pot., q. 8, a. 2; Quodl., IX, q. 3, a. 1, ad. 2.
  7. Etienne Gilson seems to speak this way when he observes, “Accidents have no existence of their own to be added to that of the substance in order to complete it. They have no other existence than that of substance. For them, to exist is simply ‘to-exist-in-the-substance’ or, as it has been put, ‘their being is to-be-in’.” Etienne Gilson, The Christian Philosophy of St. Thomas Aquinas (New York: Random House, 1956) p. 31. See also George P. Klubertanz, Introduction to the Philosophy of Being (New York: Appleton-Century-Crofts, 1955) pp. 231-232, n. 6; Leo Sweeney, A Metaphysics of Authentic Existentialism (Englewood Cliffs, N.Y.: Prentice-Hall, 1965) pp. 87-88, n. 44; James S. Albertson, “The Esse of Accidents According to St. Thomas,” The Modern Schoolman, XXX (May, 1953) pp. 265-278. In support of this view, such texts as the following are frequently cited: “…accidents do not seem to be beings according as they are signified according to themselves, but only according as they are signified in connection to substance.” In VII Meta., 1, n. 1256. Marietti ed. See note 32 above.
  8. According to Dewey, “…to know it (the true Being of the metaphysician) means to neglect its flux and alteration and discover some permanent form which limits the processes that alter in time. The acorn undergoes a series of changes; these are knowable only in reference to the fixed form of the oak which is the same in the entire oak species… Where such unifying and limiting eternal forms cannot be detected, there is mere aimless variation and fluctuation….” John Dewey, Reconstruction in Philosophy (New York: New American Library, 1952) pp. 97-98.
  1. “Potency however, since it is receptive of act, must be proportioned to that act.”; “Potentia autem cum sit receptiva actus, oportet quod actui proportionetur.” S.T., I. q. 75, a. 5, ad. 1, Ottawa ed.
  2. See Francis E. McMahon, “The Esse of Accidents: a Discussion,” The Modern Schoolman, XXXI (1953-1954) pp. 125-130; Francis McMahon and Gerald Phelan, “The Esse of Accidents,” The New Scholasticism. XLIII (1969) pp. 143-148; Barry F. Brown, “Accidental ‘Esse: A confirmation,” The New Scholasticism. XLIV (1970) pp. 133-152.
  3. Barry F. Brown, op. cit.. pp. 151-152
  4. Gerald Phelan, op. cit., p. 148.
  5. See Aristotle, Categories, Ia0-15b32.
  6. “…being (ens) is divided into ten predicaments, not univocally, as a genus (is divided) into species, but according to a diverse way of being (essendi). For the ways of being (essendi) are proportional to the ways of predicating. For in predicating something of something else, we say this to be (esse) that; and thus the ten genera of being are said of the ten predicaments.” In III Phys.. 5, n. 15; Marietti ed.
  1. “…an agent produces its like in accordance with the form by which it acts.” C.G., II, 46. Leonine ed. Also, “Since every agent acts insofar as it is in act, the mode of action must be according to the mode of the act of the thing itself; whence, something which is more hot in the act of heat causes more heat. Anything, therefore, whose act is determined to a genus, to a species, and to an accident must have its power determined to effects similar to the agent as such, because every agent produces its like.” C.G., II, 21. Leonine ed. Also, “…a being is in act through its form; it must be that operation follows its form.” C.G.. Ill, 97. Leonine ed.
  2. “…for if community was of the very notion of man. then in anything in which humanity is found, community would (also) be found.” De Ente, c. 4. n. 2. Marietti ed. Also, “…no essence is able to be understood without those (elements) which are parts of the essence.” De Ente, c. 4, n. 3. Marietti ed.
  3. As seen above in note 43, causality is limited by an agent’s nature. Now any given act of causality may be considered as a quality found in something, with respect to which Aquinas writes: “Everything which belongs to anything either is caused by the principles of its nature, as risibility in man. or else comes to it from some extrinsic principle, as light in the air from the influence of the sun.” De Ente, c. 5, n. 4. Marietti ed.
  4. Should the reader wish to pursue the question of infinite regress which often is raised in this context, he should first note that such a problem does not arise when one observes that limited being are as a class deficient with respect to the newness of existence which must needs be explained here. For a fuller treatment of this point as well as the problem of infinite regress itself, see Bonnette, op. cit., pp. 65-68, 80-126; see also, Joseph Bobik, Aquinas On Being and Essence (Notre Dame, Indiana: University of Notre Dame Press, 1965) pp. 175-182.

47 “Since therefore the divine existence (esse) is not existence (esse) received in something, but (God) Himself is His own subsistent existence (esse) as was shown above, it is manifest that God Himself is infinite and perfect.” S.T., I, q. 7, a. 1. Ottawa ed. Aquinas also notes in this same text that the ancient philosophers attributed infinitude to God
because “…they considered things to flow forth from the first principle infinitely.” This is consonant with the notion of the “Universal Donor of all new existence” referred to later in this paper.

  1. “If therefore, there were many Gods, they would have to differ from each other. Something therefore would belong to one which did not belong to another. And if that in which (they differed) were a privation, (one of them) would not be absolutely perfect; if, however, that (in which they differed) were a perfection, the other of them would be without it. It is impossible, therefore, for there to exist many Gods.” S. T., I, q. 11, a. 3. Ottawa ed.
  2. In V Meta., 1, n.751. “…nomen Causa, importat influxum quemdam ad esse causati. Marietti ed.
  3. Ex hoc autem apparet quod Deus causa est omnibus operantibus ut operentur. Omne enim operans est aliquo modo causa essendi, vel secundum esse substantiale vel accidentale. Nihil autem est causa essendi, nisi in quantum agit in virtute dei, ut ostensum est (c. 66). Omne igitur operans operatur per virtutem Dei.” C.G., III, 67. Leonine ed.
  4. Deus autem solus est ens per essentiam suam. omnia autem alia sunt entia per participationem; nam in solo Deo esse est sua essentia. Esse igitur cujuslibet exsistentis est proprius effectus ejus, ita quod omne quod producit aliquid in esse hoc facit in quantum agit in virtute Dei. C.G.,