Lewis' Presuppositionalism

I first noticed that Lewis had some things in common with the presuppositionalism of Bahnsen et al when I read this from "The Case for Christianity".

"There are all sorts of different reasons for believing in God, and here I will mention only one. It is this. Supposing there was no intelligence behind the universe, no creative mind. In that case nobody designed my brain for the purpose of thinking. It is merely that when the atoms inside my skull happen for physical or chemical reasons to arrange themselves in a certain way, this gives me as a by-product, the sensation I call thought. But if so, how can I trust my own thinking to be true? It is like upsetting a milk-jug and hoping that the way the splash arranges itself will give you a map of London. But if I cannot trust my own thinking, of course I cannot trust the arguments leading to atheism and therefore the reason to be an atheist, or anything else. Unless I believe in God, I cannot believe in thought or anything else: so I can never use thought to disbelieve in God."

Interestingly, this quote is not in "Mere Christianity" even though "Mere" is supposed to be composed of "The Case for Christianity" and other smaller compilations. I bought several copies of "The Case for Christianity" when I was in college (and the book was still in print), but I wound up giving them all away.

Although this exact quote does not appear in "Miracles", the concept is given a whole chapter near the beginning of the book. I will look for similar quotes from "Miracles" when I get the chance.


One interesting thing about the similarity between Lewis' and Bahnsen's apologetic is that I had always associated Lewis with evidential apologetics because Josh McDowell (the quitensential evidentialist) uses Lewis' trilema (Lord, Liar, or Lunatic from "Mere") argument in many of his published works (e.g. Evidence that Demands a Verdict, and More than a Carpenter). It was only after I had digested the arguments of Bahnsen that I thought to myself "I've heard that somewhere before . . ."

**UPDATE 04/09/2005**
While visiting some friends in Baton Rouge, I noticed that they have a copy of "The Case for Christianity". The above quote is from Part II, What Christians Believe, Chapter 1, page 32. The quote is deleted from page 44 of the same section from "Mere Christianity" by the same publisher, Touchtone (Simon & Schuster Inc.) 1996 ed. I'm not sure why Touchtone deleted this quote from "Mere". It was a very enlightning concept to me when I first read it, and as I said above, when I was exposed to Bahnsen and his presuppositionalism, I realized that Lewis had generally the same argument. Although of course, Bahnsen's was much more Bibically based and exegetical than Lewis'.