The phrase "ontological argument" is generally understood by historians of philosophy to refer to an argument for the existence of god. The term ontological was used by Immanuel kant to describe Descartes's version of the argument. Later historians, however, have applied the term to every form of the argument, but especially to that formulated by St. anselm of canterbury in his Monologion and Proslogion. The effect of such diversity of usage has tended to obscure essential differences in the assumptions on which various forms of the argument rest, as well as to ignore the different purposes for which the argument was employed.
St. Anselm and Descartes. The ontological argument has been used in both theological and philosophical contexts. The texts of St. Anselm and descartes are the primary examples of these two uses. According to St. Anselm, the purpose of the argument is to help to understand "in some degree Thy truth which my heart believes and loves." In contrast, Descartes's philosophical use of the argument is concerned with establishing an intellectual sanction for true judgments concerning "the essence of material things."
The direct consequence of locating the argument for the existence of God within a theological context is to see the argument as unique and applicable in only one instance. But Descartes, in formulating his version of the argument, says that he intends to show that the existence of God "would pass with me for a truth at least as certain as I ever judged any truth of mathematics to be …."(Meditation 5). For him, mathematical proofs are the paradigms for all proofs concerned with material things. Consequently he regards the ontological argument as a most general and paradigmatic kind of proof.
The failure to distinguish between the ontological argument as a model for other arguments and as a unique argument has had unfortunate consequences in evaluating the argument, especially the version of St. Anselm. Post-Kantian and contemporary criticism have generally relied on criteria of proof that are indeed relevant to any argument serving as a paradigm for other proofs, but irrelevant to an argument intended to hold in only one instance. A summary of St. Anselm's arguments supports this notion.
Argument in the Monologion. St. Anselm describes the Monologion as a soliloquy, i.e., as "a meditation on the grounds of faith." He cautions the reader first to "read diligently Augustine's books on the Trinity, and then judge my treatise in the light of those" (Monologion, pref.). The subject of the meditation is the "essence of divinity" and includes the many things that we "necessarily believe regarding God and his creatures" (ch. 1). The stated purpose of the argument is to show by reason alone how far one can come toward an understanding of the truths of belief, even if one does not believe. St. Anselm adds one most important condition regarding the strength of his argument: The conclusions drawn should be understood as having a qualified, or quasi, necessity and not an absolute necessity.
The term necessity, as St. Anselm uses it, means"always either compulsion or restraint" (Cur Deus Homo, ch. 17). Moreover, necessity refers to the actions and operations of creatures, but is not predicable of the divine nature itself. For "when we say with regard to God that anything is necessary or not necessary, we do not mean that, as far as He is concerned, there is any necessity either coercive or prohibitory, but we mean that there is a necessity in everything else, restraining or driving them in a particular way" (ibid.).
Premises and Conclusion. Since the meditation is about God and His creation, St. Anselm proceeds from assumptions that he regards as most evident regarding creatures. All men seek to enjoy only those things that they consider good. It is clear that every man sometime reflects on the cause of that phenomenon. St. Anselm's meditation on this resulted in the following argument, which he says has quasi-necessity: Every object of desire is regarded or conceived as good, where good is understood as either a useful or a noble object. Sense experience and intellectual reflection show that there are innumerable objects that vary in goodness and intensity of desirability. This multiplicity demands a single unifying principle of explanation, which also serves as the principle of order among the degrees of goodness. Such a principle cannot have the same generic characteristics as do other objects of desire. Consequently, the good that is to be the principle of all goods that admit of a variation in degree of goodness must itself not admit of any variation in degree. Hence, the principle of order and explanation of the multiplicity of goods must be a supreme good. For any good that can be thought or perceived to vary in degree can be neither self-ordering nor self-explanatory.
The notion of a supreme good means that it is good in itself rather than by participation in or by comparison with any other good. Since all other goods are good because of the supreme good, the supreme good must also be the most noble or mighty good (see good, the supreme).
The objects of desire have natures that themselves vary in degree of worth or dignity. Hence, the supreme good too must have a nature or essence that is supreme. It follows that the supreme nature is the ordering principle of all other essences or natures. But the supreme nature, being the principle of all other natures, cannot itself have an ordering principle. Hence, the supreme nature is unqualifiedly autonomous or self-subsistent. As a corollary it follows that all other natures or essences proceed from the supreme nature. St. Anselm observes finally that the meaning of self-subsistence can be expressed only analogically, or more properly, through figurative speech, but this in no way vitiates the truth of what is understood.
Summary of the Reasoning. The argument of the Monologion can be reduced to four propositions: (1) Men desire objects they think to be good—objects that vary in degree of goodness. (2) Because the variance in degree is intelligible, there must exist an invariable principle of order, i.e., a supreme good that is the source of all goodness. (3) The objects of desire have natures that vary in worth and dignity. (St. Anselm says that whoever doubts this cannot be called a man.) (4) Because the worth of natures varies in degree there must exist a supreme nature that is invariable and does not admit of comparison, i.e., a self-subsistent nature that is the originative principle of all variable natures.
Argument in the Proslogion. Most commentators do not usually regard the argument of the Monologion as a version of the ontological argument, reserving that title to the proof in the Proslogion. One commonly held reason for making such a distinction is that the argument of the Monologion assumes causal principles and is analogous to the "fourth way" of St Thomas (see god, proofs for the exlstence of). St. Anselm, however, seems to see the difference between the two to be in the number of arguments rather than in method or procedure. Whereas in his preface to the Proslogion he describes the Monologion as bound together by a number of arguments, he aspires in the Proslogion to formulate a single argument that would prove the existence of God.
Difference in Intent. A possible explanation for the difference in the number of arguments may be found in the difference in aspect and intention between the two works. The Monologion treats of God and His creation, while the Proslogion reflects on God and His attributes. The Monologion begins with assumptions concerning the actions and nature of creatures that are evidently multiple, but the Proslogion begins with a single assumption about the meaning of the term God. Moreover, St. Anselm states that the Proslogion differs from the Monologion in being a discourse rather than a soliloquy; yet it is a discourse of the soul with itself, rather than a dialogue or scientific treatise on theology. In the Proslogion, St. Anselm advises the reader to "Enter the inner chamber of thy mind; shut out all thoughts save that of God, and such as can aid thee in seeking Him; close thy door and seek Him" (ch. 1). The Proslogion is a matter of "faith seeking understanding."
The argument of the Proslogion has two distinct concerns. St. Anselm says: "And so, Lord, do Thou, who dost give understanding to faith, give me, so far as Thou knowest it to be profitable, to understand that Thou art as we believe; and that Thou art that which we believe" (ch. 2). The argument for the existence of God is restricted to the first of these concerns, i.e., understanding "that Thou art as we believe."
St. Anselm takes on faith that God is "a being than which nothing greater can be conceived" (ibid. ). This verbal formula of the belief, he says, is understood by everyone who hears the words. But what is at issue is not that one understand the words, but that what the words signify does exist apart from the understanding of the hearer. St. Anselm argues that there is a difference between something existing both in fact and in the understanding, and something existing in the understanding only. He adds that to exist in both ways "is greater" than to exist in the understanding only. Consequently, he concludes that by understanding the meaning of the term God, one must also understand that God exists apart from the understanding. The corollary to the argument is that it is impossible both to understand the meaning of the term God and to conceive that God does not exist apart from the understanding. St. Anselm does say it is, of course, possible to articulate sentences that assert the nonexistence of God, for understanding in no way coerces the use of language. But this understanding does prohibit one from conceiving as true the assertion that God does not exist, even if one is unwilling to believe that God does exist.
Synopsis of the Argument. A paraphrase of the argument shows the extent of its claim and implicitly reveals the grounds of the continuing controversy about its validity. In effect St. Anselm says; (1) I hold on faith that God exists. (2) I hold on faith that He is "that than which nothing greater can be conceived." (3) I rationally examine the content of the concepts given by faith. (4) It is impossible that the understanding of those concepts totally encompasses, comprehends, or contains the meaning of "that than which nothing greater can be conceived." (5) Hence, the understanding can now truly affirm what was already held on faith, i.e., that God exists extramentally, and is that that we believe. (6) Given the meaning of God on faith, it is impossible for reason to conceive that He does not exist.
Evaluations of the Argument. St. Anselm's argument was first challenged by a monk named Gaunilon, whose first critical objection was that St. Anselm had begged the question by assuming the definition of God, and then constructing a proof based on the hypothetical character of the definition. St. Anselm in reply calls "on [his] faith and conscience" to deny the arbitrariness of the definition (Anselm, Apologetic, ch. 1). The second objection of Gaunilon was that St. Anselm's argument is invalid because it moves without warrant from ideas to realities; he cites as an example the concept of a perfect island, and argues that on St. Anselm's grounds such an island ought to exist. The charge is denied by asserting that the argument holds only in the case of God, and, hence, is incapable of refutation by a counter-example that does not depend on a movement from faith to reason, but only on reasoning.
Later scholastics are divided on the merits of the argument. St. thomas aquinas and richard of middleton reject the argument. St. Thomas's rejection of the argument invariably turns on the question,"Whether the existence of God is self-evident?" His reply is that St. Anselm's argument does not succeed in showing that the existence of God is self-evident to us (Summa theologiae 1a, 2.1. ad 2). Other scholastics such as alexander of hales, St. bonaventure and duns scotus accepted St. Anselm's argument with modification. Scotus was concerned to show that there is no contradiction in asserting that an infinite being is comprehensible to a finite mind. As part of his proof, Scotus says he will "touch up" St. Anselm's argument: "His description must be understood thus: 'God is a being than which'—when thought of without a contradiction—'a greater cannot be thought of' without a contradiction." The effect of that qualification is reflected in the conclusion Scotus draws: "It follows that there exists in reality such a highest thinkable as mentioned, through which God is described" (De primo principio, concl. 9).
After Descartes's use of the ontological argument for strictly philosophical purposes, new criteria of evaluation were introduced. Admitting his indebtedness to Duns Scotus and distinguishing between a priori and a posteriori proofs, leibniz argued that if God is possible, He exists. A version of the argument was used also by spinoza to show that God necessarily exists, while locke rejected the argument for roughly the same reasons as those of St. Thomas. Kant's famous dictum that existence is not a predicate led him to attack Descartes's version of the argument—a rejection that was seconded by hegel, but only on the ground that St. Anselm's statement was faulty in form.
Recent discussion of the argument has been led by Norman Malcolm, who construes one form of St. Anselm's argument to conclude that God has necessary existence, a conclusion that Malcolm asserts follows from a valid argument. Critics of Malcolm's position have either found his use of the term necessity ambiguous, or have argued on formal logical grounds that the argument as presented is invalid.
The preponderance of contemporary secular scholarly opinion regards both the Anselmian and the Cartesian view of the ontological argument as logically invalid and metaphysically suspect. There is no consensus among Christian scholars about the proper interpretation and evaluation of St. Anselm's argument. Interpretations vary from seeing the argument as rigorously demonstrative to finding in it an adequate mystical theology, or regarding it as a rough but solid beginning of a systematic natural theology. Judgments concerning the validity of the argument are as varied as are the interpretations.
The position taken here is that the ontological argument of St. Anselm has nothing significant in common with the later versions of Descartes, et al. Because St. Anselm's argument is absolutely unique, it cannot be evaluated in the light of later criteria nor can it be criticized for its failure to accomplish purposes for which it was not intended. St. Anselm did not intend to make a formal proof for the existence of God. He was not concerned with making a scientific demonstration for the existence of a necessary being, or for the possibility of a necessary being, or for the non-contradictoriness of the existence of a necessary being. Instead, St. Anselm intended his argument to exemplify a method through which the understanding can find an expression for the certitude of faith or through which reason can find a way to articulate the "reasonable solidity of Truth." From this perspective the argument can be regarded as valid.
Bibliography: anselm of canterbury, Proslogium; Monologium; An Appendix in Behalf of the Foot by Gaunilon; and Cur Deus Homo, tr. s. n. dean (La Salle, IL 1954); Opera Omnia, ed. f. s. schmitt, 6 v. (Edinburgh 1946–) critical text. n. malcolm, "Anselm's Ontological Arguments," Philosophical Review 69 (1960) 41–62; articles in reply, Philosophical Review 70 (1961) 56–111. a. daniels, "Quellen, Beiträge und Untersuchungen zur Geschichte der Gottesbeweise im Dreizehnten Jahrhundert," Beiträge zur Geschichte der Philosophie und Theologie des Mittelalters 8.1–2 (1909). m. cappuyns, "L'Argument de saint Anselme," Recherches de théologie ancienne et médiévale 6 (1934) 313–330. k. barth, La Preuve de l'existence de Dieu d'après Anselme de Cantorbéry, tr. j. carrÈre (Neuchâtel 1958). r. g. miller, "The Ontological Argument in St. Anselm and Descartes," The Modern Schoolman 32 (1955) 341–349; 33 (1955) 31–38. c. hartshorne, "Logic of the Ontological Argument," Journal of Philosophy 58 (1961) 471–473.
Ontological arguments attempt to establish the existence of God by relying on one's concept of God, or the definition of the word God, without involving truths known through experience. Such arguments have had many proponents in the history of philosophy, notably Anselm of Canterbury (1033/34–1109) and René Descartes (1596–1650), as well as many detractors, including Thomas Aquinas (c. 1225–1274) and Immanuel Kant (1724–1804). Today ontological arguments are widely considered flawed, but exactly what is wrong with them remains a matter of controversy.
The locus classicus is chapter two of Anselm's Proslogion, where he calls attention to the idea of a being greater (more excellent) than any other conceivable being, that is, the idea of a maximally great being. Anselm maintains that even those who reject the existence of a maximally great being still possess the concept of one. Now—and this is the key premise—if there were no maximally great being, one could conceive of something even greater than it by conceiving of a maximally great being that exists. But it involves a contradiction to say that one can conceive of a being greater than a maximally great being. Hence, absurdity results from the supposition that God does not exist.
A common response focuses on an assumption behind the key premise, namely that something can be greater than another thing simply by virtue of existence. What is one to make of this thesis? It appears to be false for the simple reason that a comparison of greatness requires (at least) two existing things to compare. But the proponent of the argument might reply that one can compare things without assuming their existence—for example, the strength of Achilles and Hector. It is therefore important how this is done. Perhaps it simply involves a comparison of the relevant concepts. Then the key premise means, "If nothing in existence corresponded to one's concept of God, one could generate a superior concept by representing God as existing." But this seems false; one's initial concept, which failed to correspond to anything, might well have been the concept of God-as-existing.
More plausibly, to compare the greatness of two things without assuming that they exist is to ask which of them would be greater if both were to exist. But if to compare the greatness of two things they must both be thought of as existing, existence itself cannot be considered a respect in which they differ in greatness. Thus, as Immanuel Kant argued, existence is not a "perfection"; it is not a property that can contribute to something's greatness.
There are at least two ways to avoid this objection: (1) one could claim that some objects of thought possess a mode of being distinct from existence; or (2) one could alter the argument to build on the claim that necessary existence (rather than mere existence) is a perfection.
According to the first approach, there are such things as, for example, unicorns; they just do not exist. They are abstract objects of thought that lack spatiotemporal location and causal powers. Thus, one could really consider the "greater than" relation to involve two entities even if one or both of those entities do not exist. And one can treat existence as a property that enhances the greatness of something after all.
Another general objection to the ontological argument, however, causes problems for this approach. Could one not use reasoning similar to Anselm's in order to establish the existence of all kinds of things? Consider the idea of an island greater than any other island that can be conceived. Since such an island can be the object of one's thoughts, it must (on this view) be an abstract entity, even if it lacks existence. If it does lack existence, however, one could think of a greater island, namely an island that also exists. So a maximally great island must exist. But (unfortunately) the greatest conceivable island does not exist, so the argument form cannot be sound. This parody was conceived by the monk Gaunilo, a contemporary of Anselm's.
Replying to Gaunilo's parody, Anselm insisted that the argument form can only establish the existence of that which is greatest or most perfect simpliciter, and not the most perfect island or bluebird. The argument form, he suggests, will only work if the concept one begins with is that of a being that could not have failed to exist. But all islands and other material objects are the sorts of things that could be destroyed. A rejoinder might alter the parody to involve the idea of a spiritual entity with almost every perfection (e.g., a godlike being lacking only a certain amount of knowledge but nevertheless a necessary being).
Inspired by passages in Anselm that suggest a different kind of ontological argument, some proponents avoid the above dispute by focusing on God's necessary existence rather than on God's existence. This is the approach of Charles Hartshorne, Norman Malcolm, and Alvin Plantinga. For anything to count as God, they argue, it would have to be absolutely perfect. But anything that exists and yet might not have existed is thereby deficient in some way. So if God exists, God exists necessarily; it could never be that God just happens to exist. Now, one can think of a necessary being as something that exists according to all the ways the world might have been, or "possible worlds." So either God exists in every possible world or in none. But this means that, so long as it is possible that God exists, God actually exists; after all, the way things actually are is one of the ways things can be. Thus, the argument forces a dilemma between the necessity of God's existence and its impossibility.
The key question, then, is whether the existence of God (conceived of as a necessary being) is even possible. Certain philosophers have held that possibility is something conceptual, and that unless the concept of God is somehow incoherent, the existence of God is possible. Thus Charles Hartshorne has argued that either God exists or else the term God is meaningless or self-contradictory. And on the face of it, the existence of God certainly does not appear to be incoherent, like the existence of a round square. It seems perfectly conceivable.
The trouble is that the nonexistence of God also seems conceivable. And if it were even possible—assuming that God is by definition a necessary being—it would follow that God does not exist. So it would appear that the link between conceivability and possibility in this case is tenuous. And philosophers today are widely in agreement that states of affairs may be metaphysically impossible without involving any absurdity that is accessible to a priori reflection. So it is hard to see how one can assess the possibility of God's existence unless one has reason to affirm or deny God's actual existence, which is the point at issue.
See also Cosmological Argument; God, Existence of
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