Plantinga's Ontological Argument

The ontological argument has proved to be a constant source of fascination for philosophers, all the way down through the ages since its first statement by Saint Anselm, Archbishop of Canterbury, in the eleventh century. Countless words have been written on this most perplexing and confounding of theistic arguments, with new vigour being attended to it in contemporary times by such philosophers as Malcolm, Findlay and Plantinga. This constant flurry of words is an inevitable result of its totally unique nature, for it claims to be, to the antipathy of both empiricists and atheists, a completely a priori, analytic proof of God's existence.

Anselm [1078a: chs 3–5] presented his original argument in his Proslogion. His argument can be characterized briefly as this: if God is a being than which none greater can be thought and to exist in reality is greater than to exist in the understanding alone, then God must exist in reality, for if he existed in the understanding alone, he would not be a being than which none greater can be thought. Gaunilo, a contemporary of Anselm's, objected to Anselm's argument by means of analogy. As the objection is retold by Anselm [1078b], Gaunilo likened Anselm's God to a most perfect island and proceeded to prove its existence in the style of Anselm's treatise.

In the eighteenth century, Kant [1872] provided a most damaging criticism in his seminal work, Critique of Pure Reason. In this book, he argued that Anselm's treatment of existence as a property is mistaken and that only synthetic propositions are justifiably existential. (Kant's argument was developed further by Russell's [1919: ch. 16] logical analysis of the term 'exists' in his Introduction to Mathematical Philosophy.)

In his seminal paper, Findlay [1955] struck upon a most controversial ontological disproof of God's existence. After first rejecting Anselm's argument, he argued that the proper object of religious worship must be a necessary and not a contingent being. Since all existential propositions are not logically necessary, he argued, then it is impossible for God to exist. In turn, Malcolm [1964] sought to obviate Findlay's conclusion. After questioning Anselm's assumption that existence is a perfection, Malcolm reconstructed his argument in an attempt to show that the logical necessity of God's existence can be derived from his independence and eternity alone.

Hick is a contemporary theist who agrees with Hume's dictum that existential claims can only have an empirical basis. As such, he was faced with a dilemma. He cannot accept either Malcolm's or Findlay's conclusion. As a saving grace, Hick [1973] contends that the object of religious worship is a factually and not logically necessary being. Ironically, Hick derives this factual necessity from the same attributes of God that Malcolm derived God's logical necessity.

Since a substantial amount of material has already been written on the arguments cited above, I now wish to leave this historical perspective to examine in some detail the most contemporary version of the ontological argument. This latest version is advanced by philosopher of religion, Alvin Plantinga. I will assume, with him, that all of the previous versions have failed.

Copyright © 2017 Leslie Allan