This article is a brief overview of major ontological arguments. The most noteworthy feature of this article is the statement of a new parody of the Anselmian and Cartesian arguments that is obviously immune to objections adverting to intrinsic minima and maxima.

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)

Latest version of my SEP entry on ontological arguments, which first appeared in 1996. General discussion of ontological arguments. Includes a brief historical overview, a taxonomy of different kinds of ontological arguments, a brief survey of objections to the different kinds of ontological arguments identified in the taxonomy, and more extended discussions of Anselm's ontological argument (Proslogion 2), Godel's ontological argument, and Plantinga's ontological argument.

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.

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)

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 Argument The Temporal‐Contingency Argument Conclusion References (...) Appendix 1. Logic Matters Appendix 2. Formal Proofs of Some Modal Arguments. (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 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)

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.

This is a short introduction to ontological arguments. It begins with a brief characterization of ontological arguments that proceeds mainly by way of example. The rest of the discussion is given over to consideration of what looks like a very simple ontological argument. This consideration turns up many of the issues that arise when more complex ontological arguments are examined.

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)

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.

Among the rational arguments for God’s existence there is the ontological argument, originally put forth – in its classical form – by the scholastic theologian and philosopher Anselm of Canterbury and subsequently reiterated, in slightly altered versions, by some of the modern thinkers. The present paper aims to outline a comparative presentation of the ontological argument as formulated by Anselm and Descartes, respectively, and to investigate the ways in which the two Christian philosophers perceived the relationship between (...) faith and reason, between unconditional acceptance of divine Revelation and its expression in the terms of discursive thinking. (shrink)

The ontological argument- proposed by St. Anselm and developed by Descartes, Leibniz, Kant, Hegel, and Marx- furnishes a key to understanding the relationship between thought and reality. In this article, we shall focus on Hegel’s attitude towards the ontological argument as set out in his Science of Logic, where it appears as a paradigm of the relationship between thought and reality. It should be remarked, moreover, that our choice of the subject was not random and that it was (...) selected for the reason that belief in God is a preeminent social reality, inasmuch as faith in God creates His existence. Therefore, an investigation of the concept of God is an inquiry into the most profound recesses of human consciousness. The great opponents of the ontological argument, from Hume down to our day--and even Kant--have based their arguments upon the fundamental empiricist assertion that existential judgments are not analytical. This paper attempts to defend the ontological argument against its opponents. (shrink)

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.

Ontological arguments like those of Gödel (1995) and Pruss (2009; 2012) rely on premises that initially seem plausible, but on closer scrutiny are not. The premises have modal import that is required for the arguments but is not immediately grasped on inspection, and which ultimately undermines the simpler logical intuitions that make the premises seem plausible. Furthermore, the notion of necessity that they involve goes unspecified, and yet must go beyond standard varieties of logical necessity. This leaves (...) us little reason to believe the premises, while their implausible existential import gives us good reason not to. (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)

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).

This paper discusses: (1) Anselm’s ontological argument and its criticism by Gaunilo; (2) Plantinga’s ontological argument and its criticism by Mackie and Sobel; and (3) a simplified version of Gödel’s ontological argument. It also looks carefully at (4) Kant’s attempt to show that it is impossible for there to be a successful ontological argument.

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.

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)

Review of Graham Oppy *Ontological Arguments and Belief in God* (CUP).

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)

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

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)

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)

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.

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)

The modal ontological argument (MOA) proceeds from God’s possible existence to God’s actual existence. A prominent objection to the MOA is that it suffers from a symmetry problem: an exactly parallel modal ontological argument can be given for God's non-existence. Several attempts have been made to break the symmetry between the arguments. This draft is a mostly comprehensive survey of those attempts. -/- The draft was initially written as a supplement to the 2024 Summer edition of the (...) SEP entry on Ontological Arguments. However, the draft is not included in the SEP entry. (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)

The ontological argument, as understood by the first interpretation, runs as follows: The concept of God is the concept of a being than which nothing greater can be conceived. This latter concept includes the concept of a being which exists necessarily, for necessary existence is one of the perfections of an absolutely perfect being; that is, the concept of God is the concept of a being which exists necessarily. God then must conceived as existing necessarily, and hence we must (...) attribute to his essence necessary existence. According to the first interpretation, this inference from concepts alone constitutes the whole of the ontological argument. The argument is thus analytic and purely rational. (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.

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)

The ontological argument from reason aims to show that deliberative reasoning cannot be located in a naturalistic ontology, because such reasoning requires a unified, enduring self with libertarian free will. The most popular way of avoiding this argument is to claim that some version of naturalistic compatibilism suffices for human reason, because even in a world of event causation, some creatures may be responsive to reason. In this paper, I argue that the best versions of this approach either smuggle (...) in nonnaturalistic commitments or else cannot distinguish between compulsive rationality merely occurring in someone’s brain from reasoning an agent does. (shrink)

This paper introduces the special issue on Formal Approaches to the Ontological Argument of the Journal of Applied Logics (College Publications). The issue contains the following articles: Formal Approaches to the Ontological Argument, by Ricardo Sousa Silvestre and Jean-Yves Béziau; A Brief Critical Introduction to the Ontological Argument and its Formalization: Anselm, Gaunilo, Descartes, Leibniz and Kant, by Ricardo Sousa Silvestre; A Mechanically Assisted Examination of Begging the Question in Anselm’s Ontological Argument, by John Rushby; A (...) Tractarian Resolution to the Ontological Argument, by Erik Thomsen; On Kant’s Hidden Ambivalence Toward Existential Generalization in his Critique of the Ontological Argument, by Giovanni Mion; The Totality of Predicates and the Possibility of the Most Real Being, by Srećko Kovač; An Even More Leibnizian Version of Gödel’s Ontological Argument, by Kordula Świętorzecka and Marcin Łyczak; A Case Study On Computational Hermeneutics: E. J. Lowe’s Modal Ontological Argument, by David Fuenmayor. (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)

This chapter presents and critically discusses the main historical variants of the “ontological argument,” a form of a priori argument for the existence of God pioneered by Anselm of Canterbury. I assess the contributions of Anselm, Descartes, Leibniz, and Gödel, and criticisms by Gaunilo, Kant, and Oppy among others.

Review of Graham Oppy *Ontological Arguments and Belief in God* (CUP).

The article examines Kant's various criticisms of the broadly Cartesian ontological argument as they are developed in the Critique of Pure Reason. It is argued that each of these criticisms is effective against its intended target, and that these targets include—in addition to Descartes himself—Leibniz, Wolff, and Baumgarten. It is argued that Kant's most famous criticism—the charge that being is not a real predicate—is directed exclusively against Leibniz. Kant's argument for this thesis—the argument proceeding from his example of a (...) hundred thalers—although it may seem to beg the question, in fact succeeds against Leibniz. It does so because the charge of begging the question can be rebutted if one makes certain Leibnizian assumptions. (shrink)

This chapter contains sections titled: The History of the Argument The Modal Ontological Argument The Possibility of a Perfect Being: Leibniz The Possibility of a Perfect Being: Gödel The Rationality of Belief in a Perfect Being: Plantinga Summary Works cited.

I argue that spinoza's ontological argument is successful when it is understood to have two premises: (i) it is possible for god to exist, (ii) it is necessary that, if god exists, he necessarily does. the argument is valid in s5. spinoza is in a position to establish the second premise of the argument on the basis of his definitions and axioms. the first premise was assumed to be true, but, as leibniz noted, it must be established for the (...) conclusion of the argument to be forthcoming. this is one of the main problems with the argument, and it requires a solution to the problem of the attributes. certain alternate interpretations of spinoza are then argued to be deficient on textual and logical grounds. (shrink)

Proof and perception : the context of the argumentum cartesianum -- Refutations of atheism : ontological arguments in English philosophy, 1652-1705 -- Being and intuition : Malebranche's appropriation of the argument -- An adequate conception : the argument in Spinoza's philosophy -- Ontological arguments in Leibniz and the German enlightenment -- Kant's systematic critique of the ontological argument -- Hegel's reconstruction of the argument.