I think I’m going to tackle the OP from a different angle than a proof of god and stick, instead, with a logic versus materialism. This is a long post, but I believe it must necessarily be to make the point I want to make.
My first beef with materialism is that it assrets quite plainly that “everything is material”, that is, physical or affecting and affected by other physical things. It is nice to note that when everything is [something] we no longer need to define [something] (unfortunately I’ve found a few critiques of materialism which insist that it can still be defined, or at least should be). The definition is: “look around”. Dangerous grounds to stand on.
My second problem with materialism is the problem it presents for discussions of consciousness. I encountered in long-windedly but forcefully in my recent thread on private phenomena (reference private language, Wittgenstein). No one stepped up to offer a motivated discussion of how language can discuss private phenomenon; it either must be irrelevant (rug sweeping), defined as that which cannot be spoken of (rug sweeping), or denied (IMO, prima facie false: I sure as hell experience the sensation of green). I can find no account of consciousness, materialistically speaking. That does not mean I believe in a soul in any mystical or religious sense. But if I cannot account for consciousness, if I cannot recount my personal experience in language, then materialism needs to explain why we cannot form a perfect map between words and all physical things.
Now, ok, it is true that just because those private phenomena cannot be accounted for at all doesn’t mean they aren’t physical. But then, it seems to me that there should be some reason why they aren’t able to be accounted for. I don’t know, maybe not, that thread never came to any conclusions. But if the doctrine is that everything is physical, that must include consciousness. So why can’t we discuss consciousness in the same way we discuss other things that we can’t directly perceive (like, for instance, atoms).
My third problem with materialism is that it leaves no room for free will. At least, let me say, I have not seen a discussion of how free will manifests itself in a world where everything is physical (except for compatibilism, which I think sort of twists the idea of free will but whatever). Metaphysical materialism seems to demand no free will, where “free will” is a force that may manifest itself without cause and may not be acted on by anything other than itself (keep that in mind for discussion where reality is contingent on God’s will ;)). Where would it come from, and what could we do to it or with it (since it is physical)? Again, I understand that just because it can’t account for it now doesn’t mean it will never be accounted for. And though I am not sure I am a proponent of free will, I am not sure I am a materialist, either.
Materialism seems bound in thisness; which is to say: everything that is may be pointed at (I think that is a regular notion of physicalness). But if a material investigation into the nature of physical things leads us to the point where we demonstrate that individual particles don’t have a thisness (they cannot be pointed at) then I think there is a problem with the underlying assumption of thisness or at least our conception of it. In matters of theoretical science, however, it is possible that there are explantions which we may possess later that will restore thisness to reality (say, for instance, string theory).
Materialists, bound in thisness, have a hard time motivating a discussion on universals that isn’t immanent realism or nominalism, though no one who is a nominalist can claim to say anything about reality since all words are universals anyway (universals depend on sameness). But we then reach a strange case of literal pointing. Two people see a red ball, albeit from different angles. We may point to the ball and say “ball” and we may point to the ball and say “red”. We may also point to their (completely physical) brains’ state(s) of electrical and chemical activity and say “ball” and “red” as well. Right? (an epistemological limitation in saying “no”, a problem describing the sensation of green in saying “yes” since I’ve never seen it done).
Logic and materialism are not fundamentally opposed except to note the apparent discrepancy between building a complete and consistent framework of logic with which to study the universe. This is to say, we can never demonstrate that everything is physical through a rigid symbol-set unless everything can be explained by something like first-order predicate logic. Not something we would normally take very far, though I would appreciate any input on the matter (ultrafilter, if you are reading this then you might recognize my response to your research here!). (see if anyone can follow me here in the next paragraph)
I think this last point is especially important WRT free will. If everything is physical, and disregarding a symbol for “physical”, then in order to describe the universe we reach a point where we must lay out a symbol set representing classes of things: particles, forces, and so on. If there are no “random” forces in the universe, then the universe seems to be a completely deductive system (no free will). If there are random forces, how can they be described? Are they really physical, then? That is, a random force cannot be acted upon (else it wouldn’t be very random: that’s fixing the roulette wheel, my friends) but they can act. Is this not the standard conception of a “soul” or “free will”? I am at a loss to resolve this conflict.
Lib, WRT to my quoted comment. I mean to say that you can’t expect people to disagree with the proof. You can expect people to disagree with the definition or the axiom. This most recent example defines God as necessary existence period. No one would deny that necessary existence exists; it does so by definition, I would think. For me to be satisfied by a logical proof of God’s existence, I would need to see a logical description of God… a symbolic definition, should I say? A “meaningful” definition might not imply that we can simply pop it into a proof, miscible fluids being one such (possibly overused) example.
xenophon, not inly is it that “whatever must be, is” but “whatever must be, is, if it is”, except that the axiom of possibiliy asserts it “is” in at least one case, sealing the deal.
Sorry for the long post, and hope it isn’t excessively tangential.