Why are so many philosophers atheists? Can philosophers believe in God? Can they even be Christians? Check out the comment thread, specifically DSH's comment:
Jonathan's comments are precisly on target. But a careful read of my ad hominem is not "Christian philosopher," but "Biola philosopher." Let me explain.
Jonathan situates philosophy rightly as a discipline that asks ultimate questions. But the necessary prerequisite to all philosophical is the doubting of all presumptions, even the presumptions of faith.
Further, there is a strong bifurcation in philosophy. The ancient Platonic tradition is extremely metaphysical (beyond the physical), often giving "armchair speculation" as answers. A Being qua Being is conceivable to the imagination, even if such a Being is unknowable (isn't it a tenet of Christian faith that God is inscrutable?). Even Anselm's God is "the Being beyond which all other being can be conceived"). In the ancient scheme, giving imaginable ideas as answers to fundamental questions was permissable.
The Empirical tradition, on the other hand, has falsifiability as its criterion (esp. Hume, Popper, and the Vienna Circle). But the falsification of religious propositions is literally impossible (how can one falsify something that has no materiality, and the last time I checked a necessary property of God is immateriality?). I think Jonathan explained himself extremely well on these two points.
But that does not mean that one cannot be a Christian philosopher. Rather, it means if one is to adopt a philosophical "attitude," one must be prepared to question everything, including articles of faith. Most Christian philosophers simply do philosophy and leave religious tenets to the side. Some Christian philosophers, notably Aquinas in the 12th C. and Maritain in the 20th C., tried to incorporate insights from both disciplines into whole cloth. For whatever reason, such hybrids simply do not work in the modern era. Maybe when the Metaphysical tradition held sway, the hybrid might be defensible. But when the Empirical tradition came to the fore, the hybrid had to be divided, once and for all. And, let's not forget that Descartes, the "first" modern philosopher, was a Catholic Christian, and gave God as an explanation for why he "knew" his sensory experience had not been deceived. So being a modern philosopher and being a believing Christian are not mutually exclusive, but they can no longer be "held" in the same way. Faith and Philosophy are just incommensurate.
But my ad hominem was not "Christian philosopher," it was "Biola philosopher." What's the difference? What was my "silly" point?
Fundamentalist Christian academies, and Biola, Liberty, and Oral Roberts' University are certainly instances of the kind, take their faith not only as a presumption toward "everything," but literally "informing" everything. Their who raison d'etre is to incorporate a fundamentalist Christian perspective into every academic discipline, even where that perspective might be a tad bit untenable. I grant that one might admit of Christian "veil" over political science, a Christian "veil" over Language and Literature, maybe even a Christian "veil" over anthropology. But a Christian "veil" over Biology, Chemistry, and Physics is just a bit challenging. And since modern philosophy adopts the scientific method as elementary, having a Christian "veil" over "Philosophy" is contrary to both its method and its purpose. Thus, to put a Christian "veil" over philosophy is not only untenable, because the two are incommensurate, but imposing an attitude is contrary to its very method. Even the "scientific method" is not universally accepted by philosophers (e.g., Feyerabend), but as philosophical methods, only the scientific method and logic are admitted tools (but not "unquestioned" tools). Thus, deliberately casting any kind of "veil" over philosophy so that a certain perspective is entailed is wholly contraindicated. But Biola's mission is to "Christianize" academia, and philosophy's mission is to "question everything," which are totally at cross-purposes. One deliberately imposes a definite perspective onto academic questions, the other calls all presumptions into question. The two approaches are opposite each other.
And that's why I made the ad hominem "Biola philosopher." Perhaps it's not a fallacy after all.