Anon. (fresh from his smashing success writing Greensleeves) says:
We now know that the world works in a mechanistic fashion. Plagues, droughts, floods, etc. that were formerly thought to be the work of God are now recognized as the mindless workings of nature. But the question of how it all began remains unanswered. That's about the only turf left for theists to make their stand.
There is a story that when scientists concluded that there must be intelligent life on other planets Enrico Fermi asked, "But where are they?" It's that kind of reality check which separates science from philosophy.
My point is that after all the philosophical arguments are made for the existence of God we are still faced with that reality check, "But where is He?"
I hope this doesn't fall into the rude habbit of picking at rhetorical trifles, but I'm struck by the phrase "when scientists concluded that there must be intelligent life on other planets". Don't get me wrong, I find it highly likely that there's life on other planets out there. No reason for there not to be, and the probabilities seem (from what we know) to be in its favor. But where exactly could any scientist get off "concluding that there must be"? There's no "must" about any such thing until you have some evidence of it, as Fermi points out in the anecdote.
There's a deeper sense, however, in which I think the anecdote provides a useful metaphor for the discussion here. Let's say these scientists lay out some compelling reasoning for why they believe it highly probably that there is intelligent life elsewhere in the universe. Fermi responds: "But where are they?" Now the question is, has he devastated their argument?
I think not. Fermi is right to point out that there's no evidence (other than probability given certain assumptions) that intelligent life does exist elsewhere. However, unless his opponents are suggesting a situation where intelligent life would be so common as to be positively crawling out of the woodwork, his "where are they" rejoiner is only disproves the other scientist's claim to the extent that their claim suggests that the other intelligent life would be near enough (in both space and time) and similar enough to actually provide us with any evidence of its existence. If the theory is that there is intelligent life elsewhere in the universe, but it's relatively few and far between, and that highly technological civilizations are even rarer and don't last for terribly long, than a lack of obvious evidence doesn't necessarily do much to disprove the theory. (It's also a fairly speculative theory at that point, since the key prediction, intelligent life, cannot be easily proved or disproved, though the requirements for it -- frequency of the right kind of planets, etc. -- could be successfully attacked or confirmed.)
So, to address Anon's question, for all the philosophical evidence that one may muster to support God's existence, where is he?
One of the things that I often notice in these kinds of situations is that there's a tendency on the part of many agnostics and atheists who have a strongly skeptical bent to adopt a very primitive, almost shamanistic idea of what a supernatural being (if one existed) would be like. Thus, one gets statements such as: "We now know that the world works in a mechanistic fashion. Plagues, droughts, floods, etc. that were formerly thought to be the work of God are now recognized as the mindless workings of nature."
Now, the fact is that humans (including religious ones) have known for thousands of years that plagues, droughts and floods were primarily the result of natural processes. Certainly, those who believe the divine to be active in the world attribute may some natural events to God's direct agency, but few serious religious thinkers in the last 2500 years or so have attempted to attribute all natural events to God's active will. In the Christian tradition, theologians from Aquinas to Augustine and before all agreed that while God clearly allowed the natural processes which caused disasters, disasters should not necessarily be considered the active will of God. This notion even makes an appearance in scripture, where in Luke 13 Jesus comments that those killed in the collapse of the tower of Siloam were no more or less deserving of death than those who were spared.
Nor is this strictly a Christian phenomena. Reading Herodotus and Thucydides one heres of many great disasters, but even in the pagan world of ancient Greece, the cause of the disasters was generally not directly attributed to divine agency, except in the metaphorical sense.
The fact that life changing events are often the result of purely natural causes is thus hardly new. (If I were ever to post one of the lists of laws which so many bloggers compile, at the top of the list would be: Any argument which is based on the claim that basic things about life and the world we live in were not known until "the modern age" is probably flawed.)
So where then is God, if he is not in the mighty wind, and not in the earthquake, and not in the fire? Does he lurk in what Douglas Adams mocked as the realm of philosophy: rigidly defined areas of doubt and uncertainty?
I'd say that in immediate everyday experience there are two things that strongly suggest to me a more-than-physical level of existence. First, consciousness. For all the work that's been done in neuroscience (some of it very, very good), I can't see we're any closer to providing a satisfactory reduction of human thought to nothing more than neurons firing. There is without question a physical element to what goes on "in our heads", but it seems to me also pretty clear that we are mentally more than the sum of our physical parts. That suggests to me something along the lines of what is generally called a "mind" or "soul".
Secondly, it seems to me that there are certain qualities that have objective existence such as "justice", "goodness", etc. (Justifying why I believe this would take a while, so I'll leave that aside for now.) Given that, these qualities must exist in some way that is both non-physical and unchanging.
Again, neither of these will get you directly to the God found in any of the major monotheistic religions, however it is certainly enough, I think, to point on in the direction of looking for something that exists in an eternal and unchanging fashion, beyond the confines of the physical world.