I was reading from the Christian Presuppositional Apologist, Cornelius Van Till recently. In his Survey of Christian Epistemology he pretty much sums it all up,
Christianity is no hypothesis at all. It is accepted on the authority of the self-attesting Christ of Scripture and at the same time it is the presupposition without which predication is unintelligible.
Christians of this kind seem to be stating explicitly what many other Christians simply take for granted. This is demonstrated by straightforward appeals to the bible and “proof texting”. Presuppositional Apologists speak for mainstream evangelicals who don’t question the claims made in the bible, and lack the articulation skills that Presuppositional Apologists excel at.
I assess that it is a false epistemology.
You’ll notice Van Till is in fact speaking of two different authorities; one is the Christ of scripture and the other is reason (the belief that unintelligible presuppositions can’t be true). When he appeals to the law of non-contradiction by claiming that alternatives to Christianity are unintelligible, he is violating his bible-based epistemology.
If you consider it, the bible cannot attest unto reason. Even if it said explicitly, “reason is true”, rationality needs to already be presupposed by interpreting the claim as other than, “reason is not true”.
It would be very difficult but not impossible to show that reason attests unto the bible. The bible is a bundle of claims, and showing that the alternatives to some of the claims are impossible does not show that the other claims are also true.
Suppose I write on a piece of paper three things -- “God is real”, “Mahalalel begat Jared”, and “I can see through clothes”, it might be the case that alternatives to the first claim is impossible, but that doesn’t mean that my piece of paper is inerrant.
On the other hand, reason would be able to attest to Christianity if it were shown that alternatives are impossible. But Christianity cannot mean the whole of scripture. It means those claims that distinguish it from all else. That means the basic claims of theism – God exists and his fundamental attributes, and the redemptive claims specific to Christian theism– People are in sin and are therefore in need of redemption and Jesus was that redemption.
I wrote another similar post about a month ago called, If there was one thing I could tell Christians
