Principles of Natural Theology / by George Hayward Joyce, S.J.

Chapter VI. The Ontological Argument.

  1. St. Anselm's Argument.
  2. Descartes' Use of the Argument.
  3. Modern Restatements.

1. St. Anselm's argument. The proofs of the existence of God which we have hitherto considered have all been a posteriori -- proofs in which the reasoning has been from the effect to the cause. The so-called 'ontological proof' of which we shall treat in this chapter, follows the opposite, a priori, method. Just as in geometry we argue a priori from the nature or essence of the figure, as expressed in its definition, to its various properties, so certain thinkers have sought to argue from the nature of God to the fact of His existence. God, it must be remembered, exists necessarily. To exist belongs to His very essence. In this He differs from all finite things. Their existence is contingent. Their natures may be expressed in concepts, whether they exist or not: and the concepts throw no light on the question of their existence. But, if we could arrive at a knowledge of the Divine essence, we could not represent it thus apart from its real existence. Existence is not something extraneous to its nature as such, but enters into the nature as a necessary constituent. And this it is which has led men to believe that it is possible to argue from the concept of God's nature to His actual existence, precisely as we argue from essence to property.

Those who made this attempt failed to realize that though God's nature demands existence, yet our human intellect is incapable of knowing the Divine essence as it is. We are on a lower plane of being, and our powers are proportional to our nature. Of natures which are above us we have but a meagre and inadequate knowledge, reached through abstraction and discursive reason. We know something about them, but cannot really be said to know them. Hence Aristotle made his well-known comparison of the human intellect to the eyes of bats, saying that as bats are blinded by the daylight, but see in the dusk, so man has but a dim and imperfect cognition of the things which in themselves are such as to evoke the clearest knowledge: and that he knows best those sensible objects, which by reason of their material nature are incapable of being apprehended otherwise than obscurely.{1}

Yet though the proof, as we shall see, is invalid, two thinkers of great eminence -- St. Anselm, who first propounded the argument, and, subsequently, Descartes -- have not only regarded it as sound reasoning, but as the most secure of all the demonstrations of God's existence: while Leibniz, a name of hardly less authority, also eventually gave it his adhesion. It thus possesses great historical interest, and cannot be passed over in silence. Something also must be said of the claim made by certain recent writers belonging to the idealist school to hold the existence of God on the basis of the ontological proof in a somewhat altered form. It will, however, appear that their argument has but little resemblance to the proof which enjoys a prescriptive title to the name. And it is to be regretted that they should suggest the existence of a connection which has no warranty of fact.

Eadmer, Anselm's biographer, tells us how the conviction forced itself upon him that there must be some simple yet cogent argument, shewing alike that God exists, and that He is the supremely perfect Being in whom all perfections are found: how this thought beset him night and day, so as to allow him no rest: and how suddenly, one night, as he stood in his stall in choir for the recitation of the night-office, the light came, and the form which the proof should take flashed into his mind.{2}

The argument is developed in the first chapters of the work to which Anselm gave the name Proslogium seu Alloquium de Dei Existentia.{3} It may be thus summarized. The term God signifies that than which nothing greater can be conceived. Even the fool, when he says in his heart There is no God (Ps. xiii. i), has an idea corresponding to the word 'God': and his idea is what we have said, viz., that of a nature than which nothing greater can be conceived. But a nature which is of this kind is a necessarily existing nature. For were it to exist only in the mind, we could conceive something greater, viz., a nature so great as not merely to exist in the mind, but to be exigent of real existence as well. God, therefore, exists.

The argument is invalid. A nature conceived as that than which nothing greater can be thought of, must, it is true, be conceived as necessarily existing, if it exists at all. But the point at issue is: Is there such a nature? May it not be that it is a mere figment of the mind? If so, although when we conceive it, we conceive it as self-existent, it will not really exist outside our imagination.

Many critics have seen no more in the proof than a patent sophism, and have marvelled that any person of intelligence could have been deluded into regarding it as a valid argument. Such was the attitude of Anselm's contemporary, the monk Gaunilo of Marmoutier. He urged that in this way he could prove the existence of a fabled Lost Island, which was supplied with all riches and all conceivable delights. "Let it be granted," he argued, "that the idea of that island is of a land which excels all others, and you must own that my fabulous region exists: for otherwise the idea of some really existing land would excel it." And to this day it is often thought sufficient to dismiss the reasoning in some such short and easy way. Yet reflection might well have suggested that one of the profoundest intellects of his age was not likely to have been misled by a childish fallacy: that there was probably something deeper in the argument than appears at first sight. That this was so, in fact, is shewn by Anselm's reply to his critic. He there states definitely that his argument holds only of the infinitely perfect being, and that to apply it to anything finite is to have wholly misunderstood its significance.{4} This throws new light upon the saint's meaning. It is, in fact, evident that a being possessed of infinite perfection must be self-existent. If He receives existence from another, He is dependent on that other, and not infinite at all. In other words, self-existence is part of the essential nature of the infinitely perfect. Now let it be assumed that there is nothing contradictory in an infinitely perfect nature: that no impossibility is involved in the idea: that it is capable of actual existence. It follows of necessity that it exists. Here, though not in other cases, possibility implies existence. In all other cases, if we say that a nature is possible, we signify that there is no internal contradiction involved, and that consequently, given an adequate efficient cause, the nature might be realized. But here, as we have seen, there is no question of dependence on an efficient cause. The nature is its own sufficient reason. If it be possible, it exists actually. It would be a contradiction in terms for such a nature to be a mere possible -- to be capable of existence and yet not to exist actually: for self-existence belongs to its essence. Anselm's real error lies in the assumption that an infinite nature involves nothing contradictory: that its possibility is not open to question. It is true that we detect nothing in the idea which suggests intrinsic repugnance. But it is one thing to be able to affirm of some essence which we can fully apprehend, that we can see its possibility: it is another to have to content ourselves with saying, as regards a nature obscurely and imperfectly known, that we do not detect its impossibility. The latter is our case as regards the infinite. Our concept of the infinite is negative. It gives us no insight into the essential nature of the one infinite Being, but simply asserts absence of limits. Indeed, that the possibility of an infinite nature is not immediately self-evident appears from the fact that at the present day certain philosophical writers are prepared to maintain the thesis of a finite God. The position, it is true, leads to all manner of contradictions, and is incapable of reasonable defence. But the mere conception of a 'finite God' is not a manifest absurdity, as it would be were the notion of the infinite evident a priori. The possibility of an infinite being must be established by proof. And this is done by shewing a posteriori that a First Cause exists: and then that He must needs be infinitely perfect. Since the infinite exists, we know that such a being is possible. Ab esse ad posse valet illatio.

It follows from this that the argument fails for the reason which we first gave. Inasmuch as our notion of the infinite does not assure us of its internal possibility, we can draw no conclusion save that an infinite nature must be conceived as existing necessarily, if it exists at all. We cannot prove that it does exist: for we lack the power to frame an idea of the essential nature of the infinite.

It is not too much to say that few of Anselm's recent critics have understood his argument. They think it sufficient to adopt an illustration employed by Kant, and to say that we cannot prove the existence of a hundred dollars from the idea of them, no matter how good the dollars are supposed to be. Of this imaginary refutation of the ontological proof Professor Sorley well says: "It really misses the point of that proof which was an effort to discriminate between the idea of God and all other ideas." And he adds, no less truly: "Gaunilo's objection comes nearer to the point than Kant's does. Anselm had argued that existence must belong to one idea, though to one only, namely, the idea of that than which nothing greater can be conceived. To say, as Kant does, that the idea of a hundred dollars does not involve their existence, is quite irrelevant, for we can easily conceive greater things than a hundred dollars: and, in a tolerable coinage, any one hundred dollars is not better than any other. On the other hand, Gaunilo's idea of a perfect island was at least the idea of something perfect or complete of its kind. Nothing greater of its kind could be conceived. We can, however, conceive something of a greater kind -- perfect of its kind, and of a kind more perfect."{5} In past days there have not been wanting those who saw clearly where the true difficulty lay. Scotus, and, long afterwards, Leibniz, both put their finger upon the weak spot, and pointed out that the argument was inconclusive because the mind cannot affirm with certainty that an infinite nature is possible.{6}

It has become, one might say, fashionable among modern writers to say that the ontological argument is really an abortive attempt on St. Anselm's part to express a truth which he only obscurely realized: that the actual argument, as he gave it, is of minor moment: its true significance lies in the truth after which he was groping. This they proceed to indicate in one fashion or another according to their individual predilection. Two of these arbitrary interpretations will be mentioned in the last section of this chapter. Here we may at least insist on the fact that there is no shadow of doubt regarding Anselm's meaning. He meant exactly what he said, and nothing else. We have, as we have seen, his exposition of the argument in the Proslogium, and his reply to criticisms in the Liber Apologeticus: while Eadmer's biography throws further light on his intention. We could hardly ask for better documentation. He believed that just as in the real order existence is of the essence of God, so it must be in the order of thought. He forgot, as we have said, the important truth pointed out long since by Aristotle that the range of our cognitive powers is narrowly restricted, that the supersensuous world is known to us only by discursive reasoning based on sensible data, and that for this reason it is impossible for us to know the Supreme Being in aught but an imperfect way.

2. Descartes' use of the argument. Descartes' formulation of the argument is not materially different from that of Anselm. It will be well, however, to see how it takes its place in his system. According to him, the concept of God is an innate idea. He denied, as is well known, what appears to be so evident, that through sense-perception we possess direct cognition of the external world, and held that the direct object of knowledge is always internal and spiritual: that we have no immediate knowledge of anything except the ideas within the soul. These ideas he distinguishes into 'adventitious' and 'innate.' Adventitious ideas include all particular perceptions: these appear to inform us of the existence of a material world outside us; yet it would be rash to accept their testimony on this point without further guarantee. As innate we must reckon our universal ideas, and all 'common notions,' i.e., axiomatic truths. These cannot come from without: no particular impression can be the cause of an universal idea. Are, then, these innate ideas capable of giving us valid knowledge? And if so, what can we gather from them? He is enabled to answer this question by the application of his criterion of truth, viz., clearness of conception. If the innate ideas be tested by this criterion, it appears that they convey perfectly valid knowledge, but in reference only to possible existence, not to real. The note of possible existence is attached to every nature thus intellectually conceived: any one of them could be actualized in a real external order of things. Yet there is among them one which differs from the rest -- the idea of God. This contains the note, not of possible, but of real existence. It is the idea possibility may be involved in such a nature. That this is not so must be demonstrated. Descartes' contention that the idea is not gathered from created things, but forms part of the soul's initial endowment, seems to lend some colour to his conclusion that the idea cannot be a figment of our own minds, but must needs represent objective reality. But, as we need hardly point out, his whole theory of innate ideas is baseless. The idea of God, the perfect Being, stands in no need of recourse to any such hypothesis. We reach it without difficulty by considering the finite perfections of the created world, and then forming a negative idea, in which perfection is conceived without any limit.

The importance attached to the argument in the Cartesian philosophy led Leibniz to give his attention to it. He recognized that if a self-existent being be possible, it follows that such a being exists: that in this case to conceive the essence as possessing potential, though not actual, existence would involve a contradiction, since such a nature is ex hypothesi its own sufficient reason. He saw, moreover, that the defenders of the argument had failed to make good this possibility. Yet he gives it as his judgment that the possibility should be assumed till the contrary was demonstrated: that it is for the opponents to prove the impossibility of a self-existent being: and that till this is done, the argument retains a high degree of value. Practically, however, this is not the case. The objective possibility of an infinitely perfect being is less evident to the mind than is the existence of God. Those who deny the latter are not likely to make their own refutation easy by admitting the possibility of an infinite being.

Kant criticizes the ontological proof at length in the Critique of Pure Reason. It is frequently assumed that his refutation was decisive; but in point of fact his arguments are wide of the mark. He throughout treats the notion of the infinite nature as though it were on a par with other natures, and could be represented either with or without existence. He fails to meet the fundamental contention of those who defend the proof, viz., that the nature of the infinite is inconceivable apart from real existence: and that, therefore, in this case, and in this case alone, we can establish the existence from the concept of the nature. The arguments on which he relies are two: (1) that if we deny the existence of a being, no question of repugnance is possible, for all notes are sublated: none are left between which repugnance can arise: and (2) that real existence is extrinsic to the essence of any being, and that consequently it is impossible to argue from the concept of the essence to real existence. The first of these arguments is invalid, if the possibility of a self-existent nature has been admitted. For, as we have seen, in the case of this nature possibility and actuality are inseparable. Hence the denial of existence is repugnant to what has been already admitted. Now Kant does not question the possibility of the self-existent being. Indeed, in admitting that He is a legitimate subject of predication he equivalently concedes the possibility. Of the self-contradictory nothing can be said. The second argument is valid against finite natures, but of no force whatever against that particular nature with which the dispute is concerned. Hence, although Kant dismisses Leibniz's considerations as valueless, there can be no question that the latter's criticism shewed a truer appreciation of the argument, and is of far higher worth.

3. Modern restatements. We have adverted above (§ 1) to the claim made by certain modern writers to explain what St. Anselm was really seeking to express by the ontological proof. Before we leave the subject, it seems advisable to notice two of these restatements. Little more will be needed than a bare account of the explanations offered: for it will appear at once that there is no connection whatever between the original reasoning and the alleged interpretation. The writers in question attribute to Anselm some thought which for themselves is of considerable importance, and maintain that this must have been in his mind when he framed his argument; but in no instance is there the smallest ground for the assertion. Such a proceeding presents certain attractions which sufficiently explain it. In the first place, it seems to solve the problem how a great intellect was led into a patent fallacy. And it must be remembered in this connection that most of those who offer these solutions see no more in the ontological argument than did Kant, and consequently hold it to involve a manifest paralogism, most perplexing in a thinker of acknowledged eminence. And, secondly, a certain support is won for their own view, if it be the case that the minds of two such men as Anselm and Descartes were travelling, even though unconsciously, in the same direction.

The first of these interpretations to which we shall call attention is propounded by Lotze in his Microcosmus. After declaring that Kant's refutation of the argument has shewn once and for all that as a logical proof it is wholly valueless, he proceeds:

"Anselm, in his more free and spontaneous reflection, has here and there touched the thought that the greatest which we can think, if we think it as only thought, is less than the same greatest if we think it as existent. It is not possible that from this reflection either anyone should develop a logically cogent proof, but the way in which it is put seems to reveal another fundamental thought which is seeking for expression. . . . It is an immediate certainty that what is greatest, most beautiful, most worthy, is not a mere thought, but must be a reality, because it would be intolerable to believe of our ideal that it is an idea produced by the action of thought but having no existence, no power, and no validity in the world of reality. . . . Many other attempts may be made to exhibit the internal necessity of this conviction as logically demonstrable; but all of them must fail. On the contrary, the certainty of this claim belongs to those inner experiences to which as to the given object of its labour, the mediating, inferring, and limiting activity of cognition refers."{8}

Professor Pringle Pattison's view is substantially identical{9}: and Professor Sorley, likewise, regards "the demand that our highest ideal, the best and most perfect being which we can conceive, shall not be severed from reality" as one of the two motives which underlie the argument.{10}

Nothing of this kind was in Anselm's mind. And to offer this as the true meaning of the argument is simply misleading. Such an attitude is only comprehensible in those who, by denying the value of the ordinary proofs for God's existence, have kicked away the ladder which supported them, and are reduced to a blind affirmation unsupported by valid reasoning. Anselm was not in this case. In his Monologium he had given what he held to be an absolutely solid demonstration of the existence of God. His long and painful effort for an a priori proof was no struggle to justify his belief in his ideal. It was, as Eadmer tells us, a search for a short and compendious demonstration of a conclusion already incontrovertibly established by valid but somewhat lengthy reasoning.

Of greater importance than the foregoing is the interpretation offered by idealist thinkers whose system is more or less closely related to that of Hegel. According to them, the truth which lies at the base of the ontological argument is, not that the idea of God as such involves His existence, but that every judgment of the intellect is found in the last resort to presuppose an ultimate Truth -- the ground of all reality -- which is God. We shall have to deal at some length with this system of philosophy in a later chapter (chap. xv.). Here it must be sufficient to say that its defenders hold thought and being to be identical. There are not, they contend, two distinct orders -- an order of being and an order of thought -- but a single order of experience, which may be viewed under either one of these two aspects. Furthermore, truth does not lie in the correspondence of thought with things, but in the coherence of our judgments into a consistent whole. Our particular judgments are partial and inadequate: and taken in their singularity, are found inconsistent with other aspects of reality. Perfect truth can only be realized in a judgment which is adequate to reality in its entirety. Hence all thought points on to an ultimate Truth: the conditioned points to the Absolute: and this is God. To many Hegelians, however, as we shall see, the Absolute is not a Person at all: and though they may still speak of the argument as a proof of God's existence, the term God is employed in a sense peculiar to their system, and the argument has, in fact, no bearing on God's existence at all. Others, at the cost of inconsistency, maintain that the Absolute is a conscious Thinker, whose experience is prior to our own, and embraces in its range that of all limited individualities such as ourselves. To this class belong the majority of English idealists. In illustration of this interpretation of the argument we cite a passage from Professor Edward Caird. He condemns the proof as used by Anselm and Descartes, and then adds:

"But it is quite a different thing, if we regard that argument as pointing to the ultimate unity of thought and Being, which is at once the presupposition and end of all knowledge. Taken in this sense, the argument is but one example of the principle that abstract and imperfect conceptions of reality give rise to contradictions, and so force us to put them in relation to the other conceptions which complement and complete them. For pure thought cannot be conceived as dwelling in itself, but only as relating itself to existence, to a world and in time and space; and it is only (1) through the opposition between itself and such a world, and (2) through the transcendence of that opposition, that it can come to full consciousness of itself. In the language of theology, the Ontological argument expresses the doctrine that God as a spirit is necessarily self-revealing in and to the world."{11}

Our estimate of this explanation will appear when we come to discuss the system which it succinctly summarizes. It does not seem necessary to point out that there is no vestige of a connection between St. Anselm's thought and this piece of Hegelian metaphysics.

{1} Aristotle, Metaph., II., c. i., 993b10; cf. supra.

{2} Eadmer, Vita Anselmi, c. iii., n. 26; Migne, P.L., 158, 63.

{3} Migne, P.L., 158, 227.

{4} Liber Apologeticus contra Gaunilonem, c. 3; Migne, P.L., 158, 252.

{5} W. R. Sorley, Moral Values and the Idea of God, p. 311-313.

{6} Scotus, in I.Sent., dist. 2., q. 2., n. 32; Leibniz, De la démonstration Cartésienne de l'existence de Dieu.

{7} Principia, I., nn. 13, 14; Méditations, n. Réponses aux premières objections (ed. Cousin, Vol. I, 389). Descartes employs other proofs of God's existence; but he seems to have regarded this as the most important: vide Raisons qui prouvent, etc. (ed. Cousin, I, 460). He gives it only the second place in the Meditations; but there were special reasons for this order.

{8} Microcosmus (Eng. trans.), II., pp. 670, 671.

{9} Idea of God, p. 240.

{10} Moral Values and the Idea of God, p. 315.

{11} The Philosophy of Kant, p. 645; cf. also John Caird, Introduction to the Philosophy of Religion, p. 144 seqq.

<< Principles of Natural Theology >>