Can We Prove the Existence of God?

The Gospel Coalition invited me to answer the titular question in two thousand words or less. Go here to read the result. Unfortunately, due to the word limit, a number of witty asides and clever illustrations from the first draft didn’t make the final cut. (You’ll just have to take my word for that.)

7 Responses to Can We Prove the Existence of God?

  1. Prof. Anderson,

    It’s a very well-written and, perhaps more importantly, well-constructed essay. Of course I disagree with just about everything in it, but that’s to be expected.

    However I did want to comment about one point in particular. You write:

    If they fail to see that the existence of God follows from what they already believe or take for granted, or if they prefer to abandon other beliefs rather than to affirm the existence of God, the problem doesn’t lie in the proof.

    This seems false. It could be, for instance, that the premises in a valid argument are already accepted by a person, but one of those premises is false.

    Even if the premises happen to be true, though, there can still be plenty wrong with the argument. Namely, an argument can exploit misconceptions to trick someone into believing something true, but for the wrong reasons.

    For example, consider a person who has never before encountered the problems associated with vagueness. This inexperienced person may naively affirm, for a suitable collection of natural numbers n, the premises that “if n grains make a heap, then n-1 grains make a heap.” Ordinarily this sort of move would be used towards “proving” an absurdity, say that zero grains make a heap. Suppose instead it was used to prove something that happened to be true, but was nevertheless quite dubious, for instance that nine grains make a heap. Consider:

    If 50 grains is a heap, then 49 grains is a heap.
    If 49 grains is a heap, then 48 grains is a heap

    If 10 grains is a heap, then 9 grains is a heap.
    50 grains is a heap.
    Therefore, 9 grains is a heap.

    Now, I think all these premises are true, and so too the conclusion. However this is not a good argument as presented to our subject, since his reasons for accepting the first 41 premises are the same reasons he would have for affirming similar premises, at least some of which must be false since from them it would follow that zero grains make a heap, which is absurd. In this way, the argument—which, again, is perfectly sound—exploits an error which our inexperienced subject had committed. In so doing, it alerts him to his error, and thus he is moved (quite rationally) to doubt the premises.

    Also, I’m not sure if you intended this, but you seem to imply that if a person reacts to a sound argument by doubting previously-accepted premises instead of embracing the conclusion, then this is somehow indicative of an irrational bias against the conclusion. Hopefully you agree that this is not actually the case.

    Especially, if one has pre-existing beliefs about what we can expect arguments to accomplish given their structure and content, then that can lead us to rationally doubt premises which were previously acceptable to us. For instance Anselm’s ontological argument strikes many folks as bizarre since it appears to accomplish what some might consider impossible—proving the existence of an object external to ourselves from nothing more than reflecting on the meaning of our terms. Maybe you think that Anselm’s argument was sound, but even if so, hopefully you will agree that someone who doesn’t understand the relevant differences (if any) between Anselm’s proof and Gaunilo’s parody should not accept either one, despite having started off naively believing all their premises.

    Anyway, those are some thoughts.

    Regards,
    Ben

    • You weren’t persuaded, Ben? Well, I guess that just proves my point! ;)

      Seriously, thanks for the comments. You raise some good points. I’m sure you can appreciate that when you’re up against a word limit, you can’t nuance and qualify every statement in the way that you would want to in a more thorough treatment.

      It could be, for instance, that the premises in a valid argument are already accepted by a person, but one of those premises is false.

      Sure, but remember that at that point in the article I was assuming that the theistic argument in question is sound. I’d also add that TAG is a theistic argument that can proceed even from false premises. “Antitheism presupposes theism” — remember? :)

      I’m not sure I understand your sorites illustration. You suggest that the argument is sound, but that the person has been misled into accepting the (true) premises for the wrong reasons. Fair enough. But why think that the fault lies in the argument?

      In any event, I accept your general point that there can be other problems with an argument than the ones I identified. There were certain other assumptions lying behind my statement (e.g., assumptions about basic beliefs and proper function rationality) that I had to gloss over for the sake of conciseness.

      Also, I’m not sure if you intended this, but you seem to imply that if a person reacts to a sound argument by doubting previously-accepted premises instead of embracing the conclusion, then this is somehow indicative of an irrational bias against the conclusion. Hopefully you agree that this is not actually the case.

      I agree that it isn’t always the case.

  2. Boy I wish there was a preview function on this site… formatting woes!

    • Fixed.

      I’m still looking for a reliable (and free!) WP plugin that will support previewing or user-editable comments.

  3. Loved that article! It was interesting that after I posted it on Facebook, several of my friends who are atheists “liked” it. Perhaps there was some baggage there of past debate experiences with Christians (probably myself) who thought they had developed a conversation-stopper argument for the existence of God. From my perspective, it encouraged me to go deeper than a quick fix logical argument, but rather engage in some specific validity of the premises within the argument. I have a friend who became an atheist after several years of being in the church and he wants to chat about it. Should be interesting!

  4. Prof. Anderson,

    Oh, that’s great that you fixed the formatting of my post, thanks! (It’s also a little troubling that wordpress allows blog owners to selectively modify the contents of comments, but oh well, I guess it’s for the best in this case.)

    Anyway, about the sorites thing… What’s wrong with the argument in that example is that, first, it fails to persuade, and second, it *should* fail to persuade since it alerts an observant person to his bad reasons for having (up to that point) naively assumed the premises.

    Regards,
    Ben