Van Til on an Absolutely Certain Proof of Christianity

Cornelius Van Til, The Defense of the Faith, 4th ed., p. 381:

The best, the only, the absolutely certain proof of the truth of Christianity is that unless its truth be presupposed,there is no proof of anything.

Van Til's  claim, to employ some Kantian jargon, is that the truth of Christianity is a condition of the possibility of proving anything. That's quite a claim. Let's put it to the test.

One can prove that the null set is unique by reductio ad absurdum. We begin the reductio by assuming that the null set is not unique, that there are two or more null sets. By the Axiom of Extensionality, two sets differ numerically only if one has a member the other doesn't have, or vice versa. But the null set, by definition, has no members. So the assumption leads to a contradiction. Therefore there cannot be two or more null sets. Hence the null set is unique. 

The proof presupposes the Law of Non-Contradiction (LNC), and I am willing to grant that LNC and the other laws of logic can be argued to presuppose in their turn the existence of an omniscient necessary being. One argument to this conclusion is the Anderson-Welty argument which I critically examine here. I conclude that, while the argument is not rationally compelling, it does contribute to the rationality of belief in God.  In other words, the Anderson-Welty argument is a good reason to believe in the existence of God. It does not, however, establish the existence of God in a definitive manner. It does not show that the existence of God is absolutely certain.

At the very most, then, one can plausibly argue to, but not prove, the existence of an omniscient necessary being whose existence is a presupposition of our rational operations in accordance with the laws of logic.  But this is a far cry from what Van Til asserts above, namely, that the truth of Christianity with all its very specific claims is a condition of the possibility of proving anything. Trinity and Incarnation are among these specific claims. How are these doctrines supposed to bear upon the laws of logic?  Perhaps the Van Tilians have an answer to this. If they do, I would like to know what it is. But not only is Van Til's conception of God Christian, it is also Calvinist so that all the characteristic claims of Calvinism are also packed into the conception of a God that is supposed to be a condition of the possibility of all  proof.  How does predestination, for example, bear upon the laws of logic?

Comments

[The Bad Ostrich]

Is there no prefatory remark to the text you cite, or subsequent explanation? Otherwise it reads very strangely.

[Casey]

I myself have been frustrated by Van Til's bald assertion that Christianity must be assumed if there is to be proof of anything. I think it was intellectual malfeasance on his part not to have clarified this statement; even if he did so elsewhere, he should have done so near where he actually said it. Perhaps he meant something like the Anderson-Welty paper spells out (in philosophical detail, none of which I see in Van Til). Another possibility: given Van Til's emphasis on the need for Christianity, and not just theism, to be presupposed if any proof is to be possible, I wonder if he may have meant that Christianity must be presupposed precisely because Christianity is true, and being true, our intellects are darkened to the point of not being able to ever prove anything unless we presuppose (i.e. accept on faith, and without argument) the Christian faith, thus rehabilitating our reasoning powers and opening the door to reliable reasoning. I know from his essay "Why I Believe in God" that Van Til thought that as long as a person remains unregenerated, he will be able (and will be motivated) to twist evidence for God such that it suits his preconceived (non-Christian) worldview (Lawrence Krauss: "The world did begin, BUT..."), whereas one only sees things as they are after Christianity has been "presupposed," i.e. accepted in the mode of a true believer.

[BV]

Casey,

The quotation is taken from a 427 page book. To be fair to the man you have to read the book. I have read big chunks of it, and I am trying to understand his thesis and the reasoning that supports it. So far, the quoted bit strikes me as preposterous. But I have an open mind and will read on.

>>I wonder if he may have meant that Christianity must be presupposed precisely because Christianity is true, and being true, our intellects are darkened to the point of not being able to ever prove anything unless we presuppose (i.e. accept on faith, and without argument) the Christian faith, thus rehabilitating our reasoning powers and opening the door to reliable reasoning.<<

Good comment. It raises the question what Van T means by 'presupposition.' I get the impression he uses the word in different ways. In one sense, to presuppose Christianity is just to assume that it is true. He was brought up Calvinist, he unshakably believes it to be true, and so he feels no need to inquire whether it is true. Why inquire into what one knows to be true? In this sense Calvinist Xianity is an absolute presupposition, an ultimate starting point that must not be called into question.

But this doesn't sit well with his transcendental method whereby he starts with some obvious fact and then attempts a regress to the conditions of its possibility.

For example, we make assertions and we draw inferences from the propositions asserted. But asserting would not be possible if there were no truth, and valid inference would not be possible were there no logical laws. So truth and the laws of logic are transcendental presuppositions of these activities we engage in. From there we can regress to an omnisicient necessary mind as the ultimate condition of the possibility of truth and laws of logic.

So there are these two senses of presupposition or presuppositum, absolute and transcendental.

My view is that the transcendental regress cannot take us to the Calvinist God or the Thomist God either. It gets us to a presupposition FOR something but not an absolute presupposition. And so Van T just posits the Calvinist God. The latter is *aus der pistole geschossen* to borrow a line from Hegel.

[Brian Bosse]

Hello Bill,

I believe the Van Tillian argument used to establish the claim for the necessity of Christian theism is along these lines: (1) the Christian worldview can account for rationality, intelligibility, proof, etc...; (2) no other worldview can provide an adequate account. Assuming there is rationality, intelligibility, proof, etc..., this would establish the claim. Dr. Greg Bahnsen in Van Til’s Apologetic – Readings & Analysis states...

"Within the Christian worldview, knowledge…can be affirmed and made intelligible. But when we...look into the character and consequences of non-Christian philosophies, we encounter the repeated epistemological failure of unbelief. Christianity is therefore epistemologically necessary; that is, it must be true because of the impossibility of the contrary (p. 487)."

To this end, Van Til divided all worldviews into two categories: (a) the Christian worldview submitting to God’s authority; and (b) all other worldviews. Those in the latter category all suffer from the defect that they are “based on human autonomy”. Again, Bahnsen says...

"In the argument between Christian faith and unbelief, it is important to remember that the two positions are mutually exclusive: one submits to the authority of God’s revelation; the other asserts human autonomy...Either the living or true God is a person’s philosophical point of reference and final authority, or in some fashion man...takes over that position and function. Despite ‘family squabbles’ and secondary deviations among unregenerate men in their thinking, they are united at the basic level in setting aside the Christian conception of God (pg.s 487-489)."

Presumably, it is the shared defect of human autonomy by all other worldviews that makes it impossible for them to provide the necessary preconditions for intelligibility. There really are two claims here: (1) all non-Christian worldviews are based on human autonomy; and (2) all worldviews based on human autonomy fall into epistemological failure. I have never seen these two claims demonstrated - only asserted.

Bill, you point out in the last paragraph of your post that Calvinism is packed into their conception of God, and ask how predestination bears upon this. I can do one better. I have heard Greg Bahnsen go so far as to say that paedo-baptism, too, is packed into this claim.

Brian

[BV]

Thanks for the comment, Brian. Are you an adherent of the Van Tilian point of view or something like it?

Why should anyone think that (2) is true? Judaism would serve just as well to account for rationality, intelligibility, etc. There are forms of Platonism that could also do these jobs.

As for (1), Christianity is committed to Trinity and Incarnation, doctrines of dubious logical coherence. Indeed, distinguished Christians from Tertullian to Kierkegaard have held that the God-Man is an absurdity, i.e., a logical contradiction, but a reality nonetheless. It is at least arguable that Christianity is for this reason less suited to ground logic than, say, Judaism.

[Chris Brown]

Hey Bill,
I am not a Van Tillian per-se, however I do agree with a great deal of his thought. I think Brian has an accurate assessment, and just to respond to your comment:

#2 follows because though alternative beliefs like Judaism or middle Platonism (or something like that)may have a logical account for the items you suggested, they nevertheless end in absurdity when pushed to their logical conclusions. Ie how can a singular monad (Judaism) beget or create? Would not the monad be sterile? To add to this you also have the issue of the one-and-the-many. And within forms of Platonism, how can a singular demiurge/monad do the same, even supposing that the Demiurge has eternal/perpetual forms co-existing within his mind? And does it really give an acceptable account of the reality of things in se (ie why shouldn't we believe this is all just a hologram if Platonism is true)?

Last, I think that Van Til's discussion of the noetic effects of sin is probably a sufficient response to Tertullian and Kierkegaard. In this discussion, he suggests that while only the Triune God of Scripture is entirely reasonable, yet our reason itself is fallen! So, to fallen, distorted, and rebellious human reason (Rom. 1) the only reasonable thing itself seems absurd. Only when reason is restored by grace do we perceive how true this reality is. That, at least, I believe to be Van Til's response to that.