[see the new pushback on this at notsobig.html, Oct 2004]
Mary...

About the question "Can God make a rock so big he cannot pick it up?" as a problem for a view of God as omnipotent...

Couple of points here...

First, Omnipotence has historically been understood as the ability to perform any task consistent with His character and essence. (At least that's the classical definition/understanding of it). This would exclude 'things' like...

Re his character:
It is impossible for God to lie (He actually is the one who told us this in the scriptures).
It is impossible for God to break an promise.
It is impossible for God to deny his existence and character (tantamount to lying, of course).
Re his essence:
It is impossible for him to split into two essences (a la cell division).
It is impossible for him to will himself out of existence.
(These above statements are beyond the scope of this email.)

Secondly, there are some things that we can build pseudo-sentences about, that actually don't end up being 'tasks'...some can be quite comical...
"Can God make this question into a declarative sentence?"
"Can God change the subject of this sentence to 'jello'?"
"Can God make this sentence so long that he cannot read it?"
"Can God make the slithy toves gyre and gimble in the wabe?"
(for any fellow Alice-in-Wonderland-Enthusiasts out there!)
These 'sentences' seem odd to us, for they look like regular sentences, but they have what philosophers of language call 'ungrammaticality' (cf.Language and Reality--An Introduction to the Philosophy of Language, by Michael Devitt & Kim Sterelny, MIT Press, pps.89-92).

Then there is another class of sentences in which grammaticality is present, but there are improper referents and relations, similar to the linguists' favorite: "Colorless green ideas sleep furiously". These sentences (and any questions based upon them like "Do colorless green ideas sleep furiously?") are said to have no truth value (neither true nor false)--they just don't have any meaning to BE true or false.

It is into this category that the following sentences/questions fit:
God can make a square circle.
(and the Q-version of it: Can God make a square circle?)
God can make colorless green ideas sleep furiously.
God can make a rock so big it turns into a peach.
God can make a rock so invisible that it casts a shadow 2 parsecs long!
It is in this category that the famous "God can make a rock so big he cannot lift it" fits. As a 'sentence' it actually has no meaning, and hence is neither true nor false.

Hope this helps...(And doesn't confuse the issue any farther!)

Glenn
The Christian ThinkTank...[http://www.Christian-thinktank.com] (Reference Abbreviations)