Olaf, here's a quote from Michael Kruger original article "The Sufficiency of Scripture in Apologetics", TMSJ Spring 2001, that you missed:

Every philosophy must use its own standards in proving its conclusions; otherwise it is
simply inconsistent. Those who believe that human reason is the ultimate authority
(�rationalists�) must presuppose the authority of reason in their arguments for
rationalism. Those who presuppose the ultimacy of sense experience must presuppose
that in arguing for their philosophy (�empiricism�). And skeptics must be skeptical of
their own skepticism (a fact which is, of course, the Achilles heel of skepticism). The
point is that when one is arguing for an ultimate criterion . . . one must use criteria
compatible with that conclusion. If that is circularity then everybody is guilty of
circularity.
The words of Bahnsen sum up the need to argue presuppositionally:
The Believer must defend God�s word as the ultimate starting point, the unquestionable
authority, the self-attesting foundation of all thought and commitment. . . . The fact that
the apologist presupposes the word of God in order to carry on a discussion or debate
about the veracity of that word does not nullify his argument, but rather illustrates it.


Notice that big IF in there. He does not say it's circularity, he postulates the question of "what if" that is circularity, and used his IF as an excuse to dismiss all arguments that do not begin and end with the Bible. Overall, his article is just 18 pages of a weak attempt to justify Christian use of one of the weakest forms of argument that exists.

You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.

You cannot over estimate the unimportance of nearly everything. John Maxwell