Is The Question of God Intellectually Undecidable?

It seems that Pascal thought the question of God undecidable on the basis of evidence: The evidence just isn’t there one way or the other – that God exists or that God does not exist -, and we have no reason to presume one or the other. William James, too, seems to have thought something similar, and is famous for his claim that the question whether God exists “cannot by its nature be decided on intellectual grounds.”

William James

The fact that some very intelligent people have held to this position should give us pause and cause us to ask: Is this right? Is there truly insufficient evidence to support the belief that God exists and insufficient evidence to support the belief that God does not exist?

An interesting and important question. And a difficult one. A very, very difficult one — too difficult for the space or the energy (or the ability) I have available. I will, however, mention my suspicion on the matter: it is true for some people that they haven’t sufficient evidence one way or the other — a suspicion likely to be unpopular with apologists on all sides of the fence). I would like to briefly consider a more modest question:

Suppose it is true that the question of God is undecidable on the basis of evidence (or it is for some people; or it is undecidable on the basis of evidence immediately-accessible-without-a-certain-sort-of-inquiry, or some other qualified thesis). What would this mean?

Obviously, lots. But here’s three implicatory questions that come immediately to mind. The first is for the enterprise of apologetics. Apologists conduct their business on the basis of reasons. Almost always these reasons constitute evidence – and publicly available evidence at that. A Christian apologist, for instance, attempts to give an audience evidence which will lead them to believe such-and-such about God — and this evidence is not supposed to be evidence that only the apologist has access to; the evidence is intended to move the audience. The goal is to persuade, and the appeal to evidence invisible to someone is never very persuasive.

Now if the question of God is undecidable, the Christian apologist – at least when it comes to this question – will not have evidential reasons to appeal to. Now what? There are a few options: (1) The apologist quits his job. (2) The apologist quits appealing to evidence and starts attempting to manipulate the audience. (3) The apologist appeals to reasons which are not evidential (if such reasons exist). Which option to choose?

A second implicatory question: If the question of God is undecidable on the basis of evidence, does this commit us all to agnosticism? Is the agnostic the only rational one?

A third and final implicatory question: If the question of God is undecidable on the basis of evidence, does this fact itself constitute evidence against the claim that God exists, since God – if he is there and if he is like most theists suppose he is – would provide us with evidence?

I have a multitude of thoughts on all three of these “suppose-it’s-true” questions, but I am interested in hearing the thoughts of others. So…thoughts?

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  1. Todd Moody - July 1, 2013, 9:35 am

    I’m not sure “decidability” is the right approach. That term comes from computer science and finite mathematics, where there are such things as “decision procedures,” i.e., algorithms. To import these concepts into epistemology in general (and natural theology in particular) is asking for trouble, I think. The existence of other minds is “undecidable” too, but that doesn’t really get us very far.

    It’s possible to have evidence for P and evidence for not-P, but it’s not possible to have proof of P and not-P. I think there’s evidence, but not proof, for the existence of God. There’s also evidence against the existence of God. Our situation is one of having to weigh the strength of the different lines of evidence.

    Atheists like to claim that there isn’t a “shred of evidence” for God’s existence. For some reason, their preferred metric of evidence is “shreds”, I’ve noticed. So from an apologetics standpoint, the first job is to show that there is, in fact, evidence for God’s existence. It’s hard to make this point if evidence and proof are conflated, and the notion of “decidability” is more at home in the domain of formal systems and proof than it is in the domain of evidence pro and con.

    I hope this helps in some way.

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    Maximilian - July 4, 2013, 11:12 am

    Hi Todd,

    The language of “decidability” and “decisions” was actually an import from philosophy and folk discourse into computer science. The William James quote – that the question whether God exists “cannot by its nature be decided on intellectual grounds” – is from 1896, well before the arrival of computer science. And it is still commonplace for us – in our nonacademic discourse – to say things like, “I just can’t decide if I should marry so-and-so,” or “I can’t decide whether to go with the vente or grande” — and to do so without implying anything at all about proofs. But this aside, perhaps “decidability”, when used in an academic or quasi-academic setting, has been taken over by the field of computer science/mathematics. If this is true, then I should have used another word (I only used this one to coincide with James’ quote).

    But I did try to make it clear that my questions revolved around the notion of evidence, not proof. Recall that I first asked: Is it true that there is both insufficient evidence to support the belief that God exists and insufficient evidence to support the belief that God does not exist? That was the big question I asked. The rest of the post was concerned with asking questions about the implications if the answer to this big question is, Yes.

    So I think we’re in agreement that evidence, not proof, is at issue. But I am still interested in hearing what others have to say about these questions I’ve raised.

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    John Bowling - July 18, 2013, 10:42 pm

    Interesting post. I may have some more to say on this later. But right I’ll just point out that from what I’ve read from Pascal (some, but not all of the Pensees) he seems to have thought that reason couldn’t decide the issue because *reason* itself can be bent this way and that way, not because the question of God was unique.

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