This was an attempt to show what is wrong with Anselm’s ‘Ontological Argument’ for the existence of God. My present view is that Peter Millican has given us a similar, but much better line of attack in his “The One Fatal Flaw….” Paper.

The ontological argument has run for a long time, regularly refuted, regularly re-appearing in a new form. Something can be learnt from its longevity. Its proponents must be on to something, or it would not have survived its many refutations. But equally, it must have been much misformulated, or it would not have seemed evidently fallacious to its many critics. Perhaps it does express a deep philosophical intimation. Certainly it has been taken to prove more than it really (...) can establish. Like many other philosophical arguments it has suffered by being made out to be more rigorous than in the nature of the case it can be. For some philosophers addressing some questions it may have been decisive in leading them to adopt one of the few options open to them: but it is quite inconclusive for others, with different presuppositions or different problems, and cannot be reduced into a valid proof cogent for all comers and compelling them to accept the conclusion it claims to demonstrate. (shrink)

There are several forms of the Ontological Argument, but it is more or less fair to say that all hang on the contention that the notion of a perfect being entails the existence of that being, since existence is involved in perfection. My first interest is in the word "perfect." The word, I think, is usually vague but it seems to me that, in the context of the proof, it has a meaning which turns out to be much (...) more pedestrian than we would suspect. The argument, if it is valid, must assert that any perfect being would have to have every possible characteristic. It alleges that existence is a characteristic and it is, of course, over this that most debate has centered. It seems clear, however, that "perfect," as employed in the argument, merely means what we would call "complete" in less august transactions. In some forms of the proof, indeed, this is made somewhat clearer since the expression "greatest possible" being is substituted for "perfect." Ordinarily, no one would be tempted to pass lightly from the notion of "that which is complete" to the notion of "the deity." Both "perfect" and "greatest possible" appear to have moral connotations and "complete" usually does not. The slide, however, is made easier by the recurrent notion that evil is not a positive quality but merely the absence of another positive quality, usually goodness. If this view is held, it certainly does follow that whatever is "complete" must be "perfect" in the moral sense as well as in the other usual senses. It is not, here, my concern to pass judgment on this notion. I am, at the moment, merely trying to trace possible sources of confusion in the argument. (shrink)

After so many centuries of debate, much of it even quite recent, as to the credibility of Anselm’s and others’ ontological arguments for the existence of God, it seems only fair to the opposition that some such argument be proposed for Satan’s existence. It must be noted, however, that in advocating the Devil’s existence, we may be no more than playing the Devil’s advocate.

Modal ontological arguments argue from the possible existence of a perfect being to the actual (necessary) existence of a perfect being. But modal ontological arguments have a problem of symmetry; they can be run in both directions. Reverse ontological arguments argue from the possible nonexistence of a perfect being to the actual (necessary) nonexistence of a perfect being. Some familiar points about the necessary a posteriori, however, show that the symmetry can be broken in favour of the (...) ontological argument. (shrink)

If the words in Spinoza’s Ethics are considered as symbols, then certain words in the definitions of the Ethics can be replaced with symbols from set theory and we can reexamine Spinoza’s first definitions within a logical–mathematical frame. The authors believe that, some aspects of Spinoza’s work can be explained and illustrated through mathematics. A semantic relation between the definitions of the philosopher and set theory is presented. It is explained each chosen symbol. The ontological argument is developed (...) through modal logic. And finally, we present some conclusions drawn from this work. (shrink)

Any argument which attempts to prove God's existence a priori based only on His nature can be termed an "Ontological Argument". Historically, however, the term is inextricably associated with the famous argument presented in Anselm's Proslogion chapter II, and with the later variant advanced by Descartes in his fifth Meditation and subsequently developed by Leibniz. Some have claimed that Anselm's argument was anticipated in the thought either of various classical philosophers (notably Aristotle, Parmenides, Plato, and (...) Zeno of Cition) or of Augustine, but although there are indeed suggestive passages in their writings, Anselm's explicit "proof" of God's existence based on his Nature does appear to be a genuinely original discovery. (shrink)

Anselm's argument has two distinct conclusions: (a) we cannot intelligibly doubt that god exists, and (b) this god, whose existence we cannot doubt, exists necessarily. if we replace anselm's vague conception of god by the spinozistic conception of substance, a defensible version of the ontological argument, understood as having these two conclusions, can be constructed. two important consequences of this analysis are: (1) the ontological argument, properly understood, deals simply with the concept of substance. it (...) is a further question whether substance ought to be understood as god. (2) the ontological argument does not actually demonstrate the existence of anything. it simply makes clear the consequences of adopting a metaphysical view which employs the spinozistic conception of substance. (shrink)

This book is a unique contribution to the philosophy of religion. It offers a comprehensive discussion of one of the most famous arguments for the existence of God: the ontological argument. The author provides and analyses a critical taxonomy of those versions of the argument that have been advanced in recent philosophical literature, as well as of those historically important versions found in the work of St Anselm, Descartes, Leibniz, Hegel and others. A central thesis of the (...) book is that ontological arguments have no value in the debate between theists and atheists. There is a detailed review of the literature on the topic (separated from the main body of the text) and a very substantial bibliography, making this volume an indispensable resource for philosophers of religion and others interested in religious studies. (shrink)

This paper aims to show that Godel's ontological argument can be parodied in much the same kind of way in which Gaunilo parodied Anselm's Proslogion argument. The parody in this paper fails; there is a patch provided in "Reply to Gettings" (Analysis 60, 4, 2000, 363-7).

Leibniz's version of the ontological argument, a modal argument for theism on which he worked most intensively in the 1670s, has two stages. The first, an “incomplete” proof, concludes that God can only be a necessary being, and therefore if God's existence is possible, then God exists. The second stage is an a priori argument that the existence of such a necessary God is indeed possible. Leibniz's fullest attempts at a possibility proof turn on his conception (...) of a most perfect being, and the chapter concludes that they are not likely to succeed, in part because of difficulties in connecting the concepts of perfection and necessary existence. (shrink)

In this short note we respond to the claim made by Christopher Viger in [4] that Anselm’s so-called ontological argument falls prey to Russell’s paradox. We show that Viger’s argument is based on a flawed premise and hence does not in fact demonstrate what he claims it demonstrates.

An argument for the existence of gods given by the Stoic Diogenes of Babylon and reported by Sextus Empiricus appears to be an ancient version of the ontological argument. In this paper I present a new reconstruction of Diogenes' argument that differs in certain important respects from the reconstruction presented by Jacques Brunschwig. I argue that my reconstruction makes better sense of how Diogenes' argument emerged as a response to an attack on an earlier Stoic (...) argument presented by Zeno of Citium. Diogenes' argument as reconstructed here is an example of a modal ontological argument that makes use of the concept of being of such a nature as to exist. I argue that this concept is a modal concept that is based on the Philonian definition of possibility, and thus that Diogenes' argument is a source of important evidence about the use of non-Stoic modalities in the post-Chrysippean Stoa. I conclude by arguing that the objections made against considering Diogenes' argument as ontological are unfounded and that Diogenes' argument clearly resembles modern versions of modal ontological arguments. (shrink)

Yujin Nagasawa accuses me of attributing to Anselm a principle (the 'principle of the superiority of existence', or PSE) which is not present in his text and which weakens, rather than strengthens, his Ontological Argument. I am undogmatic about the interpretative issue, but insist on a philosophical point: that Nagasawa's rejection of PSE does not help the argument, and appears to do so only because he overlooks the same ambiguity that vitiates the original. My conclusion therefore remains: (...) that the fatal flaw in Anselm's argument—as in many other variants—is a relatively shallow ambiguity rather than a deep metaphysical mistake. (shrink)

Daniel Dombrowski contends that: a number of versions of the ontological argument [OA] are sound; the deity whose existence is most well established by the OA is the deity picked out by Hartshorne’s neoclassical concept of God; skeptics who insist that the OA only shows that “if God exists, then God exists necessarily” are contradicting themselves, and the OA is worth a great deal since it effectively demonstrates the rationality of theism. I argue that theses and are clearly (...) false and offer a presumptive case for thinking that is false, since, absent an independent proof of God’s existence, the theist appears to be in no position to rationally assert. I also show that the Anselmian OA harmonizes rather poorly with a Hartshornean neoclassical conception of God. I conclude by assessing the philosophical and dialectical worth of ontological arguments vis-à-vis establishing the rationality of theism. (shrink)

We offer a reading of Anselm's Ontological Argument inspired by Wittgenstein which focuses on the fact that the “argument” occurs in a prayer addressed to God, making it a strange argument since as a prayer it seems to presuppose its conclusion. We reconstruct the argument as expressive. Within the religious perspective, the issues are to be focused on the right object not to present an argument for the existence of God. While this sort of (...) reading lets us understand much about the argument, it also opens new avenues of criticism, one of which is the problem of worship. (shrink)

Assuming S₅, the main controversial premise in modal ontological arguments is the possibility premise, such as that possibly a maximally great being exists. I shall offer a new way of arguing that the possibility premise is probably true.

The intention of this article is to show that the Tractatus deals with the problem of the relation between reality, possibility, and necessity as traditionally considered in the ontological argument, that is, in relation to the idea of limit, and that in Section 5.5521, we find an especially clarifying formulation of this question; the formulation itself, however, is not at all clear, so that a lengthy commentary of it is justified.

Proving the existence of God is a perennial philosophical ambition. An armchair proof would be the jackpot. Ontological arguments promise as much. This Element studies the most famous ontological arguments from Anselm, Descartes, Plantinga, and others besides. While the verdict is that ontological arguments don't work, they get us entangled in fun philosophical puzzles, from philosophy of religion to philosophy of language, from metaphysics to ethics, and beyond.

This chapter contains sections titled: The Validity of Anselm's Ontological Argument The Truth of the Anselmian Premises On Whether Anselm's Ontological Argument Begs the Question On Parodies The Validity of the Ontological Argument of Descartes and Leibniz On the Truth of the Descartes–Leibniz Premises Critiques of the Descartes–Leibniz Ontological Argument Ontological Arguments of the Twentieth Century Gödel's Ontological Argument On Whether Gödel's Argument is Sound The Modal Perfection (...) class='Hi'>Argument The Temporal‐Contingency Argument Conclusion References Appendix 1. Logic Matters Appendix 2. Formal Proofs of Some Modal Arguments. (shrink)

In this Introduction, we begin with two relatively uncontroversial matters: the broad contours of the history of discussion of ontological arguments, and the major topics that require discussion in connection with ontological arguments. We then move on to consideration of the much more difficult task of the characterisation of ontological arguments—i.e. the task of saying exactly what ontological arguments are and explaining how they differ from, say, cosmological, teleological, and moral arguments for the existence of God—and (...) then the equally contested question of the provision of general objections to ontological arguments, including, in particular, attempts to show that there could not possibly be a successful ontological argument. Finally, we consider some often-neglected questions about how to assess the merits of arguments, with a particular eye on the assessment of the merits of ontological arguments. (shrink)

I argue that Descartes intended the so-called ontological "argument" as a self-validating intuition, rather than as a formal proof. The textual evidence for this view is highly compelling, but the strongest support comes from understanding Descartes's diagnosis for why God's existence is not 'immediately' self-evident to everyone and the method of analysis that he develops for making it self-evident. The larger aim of the paper is to use the ontological argument as a case study of Descartes's (...) nonformalist theory of deduction and his method of analysis, showing how he conceives the latter as a form of philosophical therapy. (shrink)

The first aim of this paper is to try and determine what St. Anselm meant in his original argument in the Proslogion. This needs to be done because not only are the writers who expound his demonstration divided in their interpretations of it, and these interpretations quite different, but, very strangely, one does not find that they mention that there is any ambiguity and that other writers construe Anselm's words differently from themselves. Since there are in fact two arguments (...) in the classical formulation of his proof, I want to try and disentangle them, decide which of them Anselm intendedand what is its connection with the demonstration in the third chapter of the Proslogion, and thus to offer an opinion on what exactly the ontological argument of St. Anselm is. Then on the basis of the clarification, I hope to show what it was that Gaunilo and St. Thomas attacked, to touch briefly on the relation of the 17th century ontological argument to Anselm's, and in general to indicate the curious round-aboutness of the historical criticism of Anselm. Anselm argued and Gaunilo and Thomas refuted something, though not, I think, precisely what Anselm meant, or, at any rate, not all that he meant. Actually it was Descartes that Thomas refuted by refuting half of Anselm. Kant refuted the other half of Anselm in an irrelevant criticism of Descartes. So that it could properly be said that Anselm's proof has been broken by philosophers who were either only partly aware of what he was maintaining, or who never had him in mind at all. Finally, because the important thing about the ontological argument, in my opinion, is not whether it is a demonstration of God's existence, but whether its refutation is a demonstration of the impossibility of God's existence, and because this question seems to arise most sharply in connexion with Anselm's position, I want to say something about that. (shrink)

This paper shows that a recent, simplified version of St. Anselm's proof of the existence of God has its flank open to Gaunilo's objection. Reformulating Anselm's line of reasoning in terms of the distinction between mediated and unmediated causal powers, as the simplified proof does, makes it harder for Anselm's supporters to refute the objection that the ontological argument absurdly entails the existence of all kinds of fictional entities.

I argue for modal realism from the following principles:(R1) p just in case there are truth-makers for the proposition that p.(R2) If there are truth-makers for the proposition that p and the proposition that p relevantly entails the proposition that q, then there are truthrmakers for the proposition that q.(M) The proposition that p relevantly entails the proposition that possibly p.(R3) I f there are truth-makers for the proposition that q, then necessarily, if q, there are truth-makers for the proposition (...) that q.All of the above principles are to be read as necessary truths. Also, the propositional variable 'p' is restricted to propositions that necessarily satisfy R1. 'q' is not so restricted.The argument is ontological because I argue that the possibility of modal reaUsm together with R3 entails that modal realism is true. The possibility of modal realism follows from R1, R2 and M. (shrink)

General discussion of ontological arguments. (Extended the discussion of ontological arguments in the then current version of my SEP entry on ontological arguments.).

In this chapter, I overview some important topics in the discussion of ontological arguments. Particular ontological arguments discussed are those of Anselm, Descartes, and Plantinga. I then consider objections from Kant, and the implications of some parodies of these arguments. The chapter concludes with some 'questions for reflection'.

Dombrowski and Murdoch offer versions of the ontological argument which aim to avoid two types of objection – those concerned with the nature of the divine, and those concerned with the move from an abstract concept to a mind-independent reality. For both, the nature of the concept of God/Good entails its instantiation, and both supply a supporting argument from experience. It is only Murdoch who successfully negotiates the transition from an abstract concept to the instantiation of that (...) concept, however, and this is achieved by means of an ontological argument from moral experience which, in a reversal of the Kantian doctrine, depends ultimately on a form of the cosmological argument. (shrink)

This essay examines how, in the early twentieth century, ontological arguments were employed in the defense of metaphysical idealism. The idealists of the period tended to grant that ontological arguments defy our usual expectations in logic, and so they were less concerned with the formal properties of Anselmian arguments. They insisted, however, that ontological arguments are indispensable, and they argued that we can trust argumentation as such only if we presume that there is a valid ontological (...) argument. In the first section I outline the history of this metalogical interpretation of the ontological argument. In the subsequent sections I explain how Royce and Collingwood each developed the argument, and how this impacted their respective conceptions of both logic and metaphysics. (shrink)

Anselm’s ontological argument is an argument for the existence of God. This paper presents Iris Murdoch’s ontological argument for the existence of the Good. It discusses her interpretation of Anselm’s argument, her distinctive appropriation of it, as well as some of the merits of her version of the argument. In doing so, it also shows how the argument integrates some key Murdochian ideas: morality’s wide scope, the basicness of vision to morality, moral (...) realism, and Platonism. (shrink)

This article serves to explore the historical development of the ontological argument from Anselm to Present. Initially, the main goal is to introduce the lay reader to one of the most perplexing arguments for the theistic conception of God. Logically, this is an a priori argument, similar to one of a mathematical proof. Oddly, the argument has sort of fallen out of place in contemporary philosophy, apart from a reboot from Alvin Plantinga. The goal is to (...) illustrate that the initial argument as stated by Anselm seems to be an unsolved problem in philosophical inquiry. (shrink)

There are good reasons for being dissatisfied with standard criticisms of the various arguments, all of which are referred to as being “The Ontological Argument”. While refutation by logical analogy is compelling, it merely teaches us that something is amiss. It does not specify the exact nature of the flaw. The first part of this paper examines and rejects several well-known attempts at refuting and clarifying the argument(s). The second part attempts to provide a principled uniform account (...) of what is wrong by treating the arguments as resting on definitions. Then, by bringing to bear Ajdukiewicz’s exhaustive classification of definitions, we arrive at a unified account of the flaw common to such arguments. In effect we have an explication of the dictum that one cannot define into existence. (shrink)

The ontological argument in Anselm’s Proslogion II continues to generate a remarkable store of sophisticated commentary and criticism. However, in our opinion, much of this literature ignores or misrepresents the elegant simplicity of the original argument. The dialogue below seeks to restore that simplicity, with one important modification. Like the original, it retains the form of a reductio, which we think is essential to the argument’s great genius. However, it seeks to skirt the difficult question of (...) whether 'exists' is a genuine predicate by appealing instead to a distinction between having only mediated causal powers and having unmediated causal powers. Pegasus has no unmediated causal powers, but he has mediated causal powers through the thoughts, depictions, and literature in which he figures. This distinction allows us to argue about the existence of God without begging any questions. (shrink)

The creeds of religion, not being open to objective review and confirmation, are subjective only. they presume that the idea internally raises the object. this is the ontological argument extended. it remains internal, of no external import, and issues in solipsism.

One of the more famous criticisms of ontological arguments is that provided by Kant in his Critique of Pure Reason, and two of the more frequent comments on it are essentially these: Kant points out that existence is no predicate; his criticism contains several puzzling elements which can just as well be neglected, since the first point is enough. It is the intent of this paper to substantiate a protest against such analyses of Kant’s anti–ontological–arguments argument and (...) to develop certain consequences from this for current attempts to rehabilitate ontological arguments. The protest is not that such analyses are simply wrong, but that they are dangerously misleading and represent Kant’s argument as weaker than it in fact is. The substantiation is provided by the examination of the three main elements of Kant’s criticism of ontological arguments: the distinction of real and logical predicates, the analysis of uses of ‘to be’, and the discussion of concepts of possible and of actual things. The consequences for current attempted rehabilitations of ontological arguments center upon the alleged distinction of ‘existence’ and ‘necessary existence’. On the basis of the foregoing substantiation it is shown that this distinction, despite its proponents’ claims, does not make Kant’s criticism inapplicable, that the sense of ‘necessity’ remains a problem, that Kant knew quite well what he was doing in criticizing ontological arguments, and that the necessary existence allegedly proved by ontological arguments is not that which is also alleged to be religiously required. (shrink)