Christian Presuppositionalism - A General Response

I'm sure most of our readers are familiar with the style of apologetics known as Christian Presuppositionalism (CPS). In general, it argues against all other worldviews via reductio, or internal critique. One of the favorite sorts of positive arguments that CPS employ are the Transcendental Arguments for God's Existence (TAG) [also see here]. These all run along the same lines (If X, then God):
i) God is a precondition for X
ii) X exists
iii) Therefore, God exists
(X = logic, uniformity of nature, induction, morality, mathematical truths, universals...)
My student freethought group, AAFSA at UF, enjoys a hell of a faculty advisor -- a philosopher who specializes in religion and metaphysics. Prof. D. Gene Witmer (from Rutgers Phil Dept.!) is a pretty well-known guy in the world of physicalism (so far as I can tell from his numerous citations in academic works on the subject), and he teaches a phil of religion course every year, PHI 3700.

I attended a PhilSoc meeting in March where Prof. Witmer discussed the problem of evil, after which I asked him how he would respond to Van Tillian Presuppositionalists (from C. Van Til) on the PoE. He seemed taken aback, and had no idea what in the hell I was talking about. I later came to find out that this is because the CPS ideas are basically absent from awareness in academic circles (at least at secular universities). Following this, we exchanged quite a few emails discussing CPS, and I suppose I piqued his interest into the arguments and methods employed by CPS's.

On Sept. 26, I asked Prof. Witmer if he would talk to our group, and we discussed possible topics a bit before he decided to talk about CPS at our meeting 9. I have now made the abstract of the talk, and the full-text (.pdf) of his presentation available online. Please download and feel free to comment on his arguments and major points. I especially enjoyed his presentation of a "conditional PoE", wherein he argues that either there are moral facts or there aren't, but either way, the PoE shows that God does not exist.

Download the .pdf HERE.