Specter of Reason

[See Update and Update II] Graham Oppy was kind enough to draw my attention to The Nature of Necessity   (1974), in which Plantinga puts forward his modal ontological argument (MOA). Plantinga considers an objection very much like my own  (pp. 218-219):  "consider the property of no-maximality, the property of being such that there is no maximally great being.  If this property is possible, then maximal greatness is not.  But, so claims the objector, [this property is] every bit as plausibly possible as maximal greatness." Thus, Plantinga imagines the following modal counter-argument to MOA: 1) No-maximality is possibly exemplified. 2) If no-maximality is possibly exemplified, then maximal greatness is impossible. Therefore, 3) Maximal greatness is impossible. Plantinga concludes that either MOA or this counter-argument is sound.  Clearly both cannot be.  I question whether either is sound, since I question the coherence of the notion of maxim...

Exapologist was kind enough to inform me that my objection to Plantinga's modal ontological argument (MOA) is similar to one made by Peter Van Inwagen.  I've just read Van Inwagen's argument, which can be found in the sixth chapter of his celebrated Metaphysics . I don't think his argument is strong enough, as I will explain. The MOA aims to show that belief in God is just as rational as believing that God is possible.  This would be an interesting result, since belief in God is widely regarded as less rational than belief in the mere possibility of God.  So if the MOA is valid, it would be very interesting.  What I have shown is that the argument is not valid.  It begs the question.  I show this by drawing attention to the premise that God's non-existence is possible.  That premise is just as plausible as the premise of the MOA, and yet it contradicts the conclusion of the MOA.  The defeat is therefore profound.  All the MOA really shows...

I was just checking out Ichthus77 , a philosophy blog that focuses on apologetics, because it is hosting the upcoming edition of the Philosopher's Carnival.  I noticed a recent entry on the modal ontological argument as developed by Alvin Plantinga and explained by William Lane Craig.  The modal ontological argument uses possible world semantics to recast the age-old ontological argument for the existence of God.  Here it is, as introduced by William Lane Craig (copied from Ichthus77): Plantinga conceives of God as a being which is "maximally excellent" in every possible world. Plantinga takes maximal excellence to include such properties as omniscience, omnipotence, and moral perfection. A being which has maximal excellence in every possible world would have what Plantinga calls "maximal greatness." So Plantinga argues:            1. It is possible that a maximally great being exists.            2. If ...