Alvin Plantinga

Chapter 7 concluded with the claim that the Classical Argument for possible non‐existent objects depends on both the possibility of singular negative existentials and the Ontological Principle. The Ontological Principle is the principle that any world in which a singular proposition is true is one in which there is such a thing as its subject, or in which its subject has being if not existence. In this chapter, I show that the Ontological Principle is false and that whatever plausibility it enjoys is explained by the truth of a similar principle, namely, the Restricted Ontological Principle. Thus, the Classical Argument fails. Moreover, I give an account of how fictional names function in order to show that statements about fictional subjects, for example, ‘Othello is a Moor’, do not express predicative singular propositions.

I begin by introducing the ideas of possible worlds, books on worlds, and essential properties. A possible world is a broadly logically possible state of affairs that is maximal. Furthermore, for any possible world W and proposition p, let the book on W be the set S of propositions such that p is a member of S if W entails p. Finally, an object x has property P essentially if and only if x has P and has it in every world in which x exists. I use the above three concepts to give a sound argument for the conclusion that human persons are essentially immaterial.

I discuss three objections to essentialism. The first objection is from Gilbert Harman, who claims that because numbers can be identified or reduced to sets it follows that numbers cannot have essential properties. In the second objection, William Kneale argues for the conclusion that objects have essential properties only relative to a certain way of specifying or selecting the object. Kneale's argument suffers from a de re/de dicto confusion and the disambiguated reading of his argument is unsound. The third objection, Quine's mathematical cyclist, contains a similar confusion.

I clarify the notion of necessity that I will be examining in the book. In the first section, I claim that the relevant notion of necessity is ‘broad logical necessity’, which I distinguish from causal necessity, unrevisability and a proposition being self‐evident or a priori. In the second section, I distinguish between modality de dicto and modality de re. An assertion of modality de dicto predicates a modal property of another dictum or proposition, while a claim of modality de re asserts of an object that it possess a property either essentially or contingently. I conclude by examining the use of the de dicto/de re distinction in the works of Aristotle, St. Thomas Aquinas, G.E. Moore, and Norman Malcolm.

Chapter 6 is an attempt to show that the Theory of Worldbound Individuals —i.e. the theory that any object exists in exactly one possible world—is false, and that there's no good reason to deny that objects exist in more than one world. First, arguments that attempt to show that a denial of TWI entails a contradiction fail, and the so‐called Problem of Transworld Identity is no problem at all. Second, TWI should be rejected because it entails that all of an object's properties are essential to it. The defender of TWI may attempt to defend his view by adopting Counterpart Theory. I conclude by arguing that the Counterpart Theory is both semantically and metaphysically inadequate.

Chapter 7 explores the question: Are there or could there be, possible but non‐existent objects? In the first half of the chapter, I critically assess the claim that an applied semantics for modal logic commits us to the claim that there are non‐existent possible objects. I conclude that it does commit us to there being some possible world distinct from the actual world that contains some object distinct from anything that exists in the actual world; but it does not, however, commit us to the claim that there really are some things that do not exist. In the second half of the chapter, I develop a historically based argument for the conclusion that there are non‐existent possible objects, which I call the Classical Argument. Importantly, the Classical Argument presupposes that singular negative existentials are possible. I end the chapter by showing that certain objections to the possibility of singular negative existentials fail, and that such existentials are indeed possible.

I argue that each object has many essences. A property E is an essence of object x if and only if E is essential to x and in every possible world everything distinct from x has the complement of E essentially. I then elaborate on the nature of essences and examine the relationship between essences and proper names. My view is that John Stuart Mill was mistaken in his belief that proper names do not express properties. In fact, proper names express essences and I make use of this fact in addressing the famous problem of Hesperus and Phosphorus.

Chapter 9 is the first of two chapters that apply the findings of the previous eight chapters of The Nature of Necessity to some traditional problems in natural theology. The Problem of Evil is the objection to theism that holds that the conjunction of the propositions, God is omnipotent, omniscient, and wholly good and There is evil in the world, is necessarily false. The Free Will Defense is an effort to show the two propositions are compatible, and in the process of the defence, I use the concept of transworld depravity. I then prove that the possibility that every essence suffers from such depravity entails that it is possible both that God is omnipotent, omniscient, and wholly good and that there is evil in the world. I conclude by addressing special problems caused by natural evil and by arguing that the Probabilistic Problem of Evil is unsuccessful.

In Ch.10, I apply the previous chapters’ account of modality to the Ontological Argument for the existence of God. I begin the chapter by attempting to develop a sound version of the Ontological Argument based on the work of St. Anselm. I conclude that this argument fails, as does a more recent attempt by Charles Hartshorne and Norman Malcolm. I then give a modal version of the Ontological Argument that is sound and is based on the claim that the property of unsurpassable greatness is possibly exemplified. I grant that this premise is not likely to be accepted by those who do not already hold that the property is actually exemplified, but I argue that it is still rational to accept the premise.

“1950’li yıllarda dönemin büyük felsefecileri arasında dinsel inancı savunan bir kişi bile yoktu. 1990’lı yıllarda Yale’den UCLA’ya, Oxford’dan Heidelberg’e kadar birçok yerde insanın manevi yanını savunan ve geliştiren yüzlerce kitap yazılacak, sel olup akacaktı. Aradaki 40 yıllık süre zarfındaysa sadece ve sadece Alvin Plantinga vardı.” Kelly James Clark Tanrı’nın veya tanrıların varlığı sorusu felsefenin ezeli sorularından biri olagelmişse de Nietzsche’nin Tanrı’nın ölümünü ilan ettiği günden bu yana onu doğrularcasına yaşanan acılar, savaşlar, kötülükler bu konudaki tartışmaların sesini uzun süre bastırdı. Ama özellikle yüzyılın ikinci yarısından sonra palazlanan analitik felsefede meydana gelen “metafiziğe dönüş”, dine yakınlık duyan, en azından dinle ilgilenen filozofların tekrar Yahudi-Hıristiyan ve İslam geleneklerinde anlaşıldığı şekliyle Tanrı’nın varlığına duyulan inancın gerekçelerini yeniden değerlendirmelerine, konuya yeni bir bakış ve araçlarla bakmalarına vesile oldu. Alvin Plantinga’nın bu kitabı, yayımlandığı tarihten itibaren “analitik din felsefesi” alanının da en önemli ve sarsıcı eserlerinden biri hâline geldi ve Tanrı’nın ölmediğini ilan etti. Anselmus’tan Hume’a, Kant ve pozitivistlerden John Mackie gibi modern ateologlara kadar felsefe geleneğiyle hesaplaşan Plantinga, bu abidevi çalışmasında ontolojik, kozmolojik ve teleolojik tanrı kanıtlamalarının eski ve yeni biçimlerinin çıkmazlarını, meziyetlerini ve sunduğu imkânları değerlendiriyor. Tanrı’nın varlığına duyulan inanç ile diğer insanların varlığına ve zihinlerine duyulan inanç arasındaki şaşırtıcı ve sarsıcı bağlantıyı ortaya koyuyor.

Ateistler, kötülük probleminin Tanrı’nın varlığı aleyhine en güçlü argüman olduğu konusunda hâlâ ısrarcılar. Felsefe tarihine baktığımızda da Epikuros’tan Hume’a ve yakın dönemde Mackie’ye kadar uzanan bir yelpazede çeşitli düşünürler tarafından bu konuda birçok eleştirinin dile getirildiğini görmek mümkün. Plantinga bu çalışmasında felsefe tarihinin en köklü sorunlarından biri olan ‘Tanrı’nın varlığı sorusu’nu cevaplamaya çalışmakla kalmayıp felsefi bir yöntem ve soruşturmanın nasıl olması gerektiği konusunda muhteşem bir örnek de sunmaktadır. Plantinga, bu kitabıyla bizi, felsefe tarihinin en temel ilkelerinden birini hatırlamaya çağırıyor: var olanın ardındakini anlamaya çalışmak.

Is belief in God epistemically justified? That's the question at the heart of this volume in the Great Debates in Philosophy series, with Alvin Plantinga and Michael Tooley each addressing this fundamental question with distinctive arguments from opposing perspectives. The first half of the book contains each philosopher's explanation of his particular view; the second half allows them to directly respond to each other's arguments, in a lively and engaging conversation Offers the reader a one of a kind, interactive discussion Forms part of the acclaimed Great Debates in Philosophy series