Received via e-mail, this is why ‘Christian philosopher’ is a contradictions in terms. Plantinga's definition of the word ‘atheist’ applies to very few people – maybe one person I know, and I doubt that many. This means that either he is confused about the meaning of the word, either etymologically and in common use, possibly both, in which case he is no scholar, or he knows better and simply prefers to abuse straw dogs, in which case he is a liar. Given his status as ‘emeritus’, the first seems unlikely, so the second is probable.
Since Plantinga and Gutter mentioned him, let's take Richard Dawkins as an example: In his book The God Delusion, Dawkins proposes a ‘spectrum of theistic probability’, a seven-point scale of belief by which a ‘one’ is complete certainty that God exists and ‘seven’ is complete assurance to the contrary. On this scale, Dawkins, who is a proselytizing anti-theist, declares himself to be a six. That is, he is willing to look at new evidence if anyone can provide such, but he's seen it all already and would like everyone to please quit with the fairy tales. In fact, he insists. Questioned closely on the point, he later conceded (with a chuckle) that maybe he's a 6.9.
I'll go with that. I was raised Baptist. I've read the Bible (all of it), I've heard all the arguments (mostly non-arguments), I even went to a Christian junior high-school for one year (it didn't work out), and I must say that, though I won't completely foreclose the possibility of new evidence upon which I will need to modify my opinion (it wouldn't be the first time), after millennia of recorded attempts to come up with a reasonable argument for the existence of great spirits, the possibility seems pretty damned slim.
Logically, it's not my business to prove the negative – a fool's errand in any case – but rather the believer's responsibility to prove that his belief in the supernatural, which none can see nor hear, is true. (Or, at the least, barely plausible!) So far, the faithful haven't even gotten off zero, so I'm classing the entirety of spiritual belief down around Santa Claus and the Easter Bunny. Mind you, if someone can provide valid and sufficient evidence of colored-egg-laying bunnies at the spring equinox, I'll have to consider it, but let's just say that I'm not holding my breath – and I doubt that anyone will accuse me of being agnostic on the point! I'm not into imaginary friends. (Which might explain my aversion to Facebook, too.)