Gaunilo presents Anselm with a dilemma in section 7 of his Responsio: I know most certainly that I exist. But If I cannot think my non-existence at the same time, then Anselm's claim in Proslogion 3 (that my inability to think God's non-existence, while knowing most certainly that He exists, is a unique property of God) would be false. If I can do so, however, then I should also be able to know most certainly that God exists and, at (...) the same time, think his non-existence. I will show that Anselm's response to Gaunilo's attack is not adequate because it does not address the issue of certainty, which is at the heart of Gaunilo's objection. (shrink)

Gaunilo assumes that there is no greatest conceivable island, and most philosophers have followed him in this assumption. But the option was open for Anselm (and remains open for us) to bite the bullet and ‘give him his island.’ I argue that such a response is perfectly reasonable for a Platonist like Anselm, and that even a theist who isn’t a Platonist can tolerate the island as a fairly minor addition his or her ontology.

Modal ontological arguments are often claimed to be immune to the flqqperfect islandfrqq objection of Gaunilo, because necessary existence does not apply to material, contingent things. But Gaunilo’s strategy can be reformulated: we can speak of non-contingent beings, like quasi-Gods or evil God. The paper is intended to show that we can construct ontological arguments for the existence of such beings, and that those arguments are equally plausible as theistic modal argument. This result does not show that this (...) argument is fallacious, but it shows that it is dialectically ineffective as an argument for theism. (shrink)

Gaunilo argued that Anselm could prove the existence of many perfect objects, for example, the happiest island, that is, happier than any other island. More formally, Gaunilo’s arguments were intended to show that the sentence “God exists‘ does not follow from premises accepted by Anselm. Contemporary versions of the ontological proof use the maximalization procedure in order to demonstrate that God exists as the most perfect being. This paper argues that this method, which is based on maximalization, is (...) not sufficient to prove God’s existence. Thus, a “contemporary Gaunilo‘ can repeat objections raised by his ancestor. (shrink)

The purpose of this paper is twofold. First, it aims at introducing the ontological argument through the analysis of five historical developments: Anselm’s argument found in the second chapter of his Proslogion, Gaunilo’s criticism of it, Descartes’ version of the ontological argument found in his Meditations on First Philosophy, Leibniz’s contribution to the debate on the ontological argument and his demonstration of the possibility of God, and Kant’s famous criticisms against the (cartesian) ontological argument. Second, it intends to critically (...) examine the enterprise of formally analyzing philosophical arguments and, as such, contribute in a small degree to the debate on the role of formalization in philosophy. My focus will be mainly on the drawbacks and limitations of such enterprise; as a guideline, I shall refer to a Carnapian, or Carnapian-like theory of argument analysis. (shrink)

Brian Garrett claims, in defence of Gaunilo’s Perfect Island and contra Plantinga, that ‘Properly understood, the great-making qualities of an island are maximal’. This article demonstrates that they are not, thus ‘the greatest conceivable island’ remains an incoherent concept and Gaunilo’s parody fails.

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).

A metaphysical system engendered by a third order quantified modal logic S5 plus impredicative comprehension principles is used to isolate a third order predicate D, and by being able to impredicatively take a second order predicate G to hold of an individual just if the individual necessarily has all second order properties which are D we in Section 2 derive the thesis (40) that all properties are D or some individual is G. In Section 3 theorems 1 to 3 suggest (...) a sufficient kinship to Gödelian ontological arguments so as to think of thesis (40) in terms of divine property and Godly being; divine replaces positive with Gödel and others. Thesis (40), the sacred thesis, supports the ontological argument that God exists because some property is not divine. In Section 4 a fixed point analysis is used as diagnosis so that atheists may settle for the minimal fixed point. Theorem 3 shows it consistent to postulate theistic fixed points, and a monotheistic result follows if one assumes theism and that it is divine to be identical with a deity. Theorem 4 (the Monotheorem) states that if Gg and it is divine to be identical with g, then necessarily all objects which are G are identical with g. The impredicative origin of D suggests weakened Gaunilo-like objections that offer related theses for other second order properties and their associated diverse presumptive individual bearers. Nevertheless, in the last section we finesse these Gaunilo-like objections by adopting what we call an apathiatheistic opinion which suggest that the best concepts `God’ allow thorough indifference as to whether God exists or not. (shrink)

This article is a reply to Michael Gettings' criticisms of a previous paper of mine on Godel's ontological argument. (All relevant bibliographical details may be found in the article.) I provide a patch to my previous -- faulty -- attempt to provide a parody of Godel's ontological argument on the model of Gaunilo's parody of Anselm's Proslogion 2 argument.

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 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 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.

This chapter gives an exposition and critique of Anselm's Proslogion II argument.