Lies, damned lies, and material conditionals

William Lane Craig claims that atheists agree with him that, “if the universe has an explanation of its existence, that explanation is God.” It seems to me a pretty clear example of Craig’s tendency to falsely claim his opponents agree with him, but there’s one way of defending Craig’s claim that I know occurred independently to both me and at least one other person: invoking material conditionals.

Let me say at the start that I’ve never heard Craig use this defense, and the defense is so bad that it almost feels unfair to Craig to suggest he might use it. However, because it may occur to other people, and there’s some chance it’s what Craig had in mind, I think it’s worth addressing.

A material conditional is a way of understanding if-then statements that comes from formal logic.  A material conditional is defined to be false if both the “if” part is true and the “then” part is false, and true otherwise. That is to say, if the “if” part is false, then by definition the material conditional is true. If the “then” part is true, then by definition the material conditional is true. If both of these latter conditions hold, then by definition the material conditional is true.

Material conditionals are only weakly related to what we ordinarily mean by if-then statements. In particular, there’s no requirement for the “if” and the “then” parts to have anything to do with each other. This allows all sorts of bizarre sentences to count as true material conditionals. For example, “if the Earth is the fourth planet from the sun, then 2 + 2 = 5″ (because the “if” part is false) as well as “if the Earth is the third planet from the sun, then 2 + 2 = 4″ (because the “then” part is true).

Now you see what Craig could say here: “Most atheists think the universe does not have an explanation for its existence. So they think the ‘if’ part of the material conditional, ‘if the universe has an explanation of its existence, that explanation is God’ is false, so they must think the conditional is true.”

I hope, for Craig’s sake, he doesn’t mean to argue that way. To see why, suppose you (mistakenly) believe that Hong Kong is the capital of China. Then you would have to believe the material conditional “If Hong Kong is not the capital of China, then I have four arms,” because you’d think the “if” part is false. But if someone corrected you about Hong Kong being the capital of China, that would not mean you should reason:

  1. Hong Kong is not the capital of China.
  2. If Hong Kong is not the capital of China, then I have four arms.
  3. Therefore, I have four arms.

The reason you shouldn’t reason this way is that once you know Hong Kong is not the capital of China, you no longer have any reason for accepting (2), not even as a material conditional.

Also note that while “the universe does not have an explanation for its existence” commits you to “if the universe has an explanation of its existence, that explanation is God” (read as a material conditional), it commits you equally to “if the universe has an explanation of its existence, that explanation is the Flying Spaghetti Monster,” “if the universe has an explanation of its existence, that explanation is Carrier’s exploding God,” and so on.

That should underline how little material conditionals have to do with what we ordinarily mean by if-then statements.

  • Dunc

    I suspect that the main issue is hiding behind the word “explanation”… Perhaps, if pushed, Craig might argue that the laws of physics don’t actually explain anything? Is the law of gravity an “explanation” for why massive objects are attracted to each other, or is it simply a description?

    • http://www.facebook.com/chris.hallquist Chris Hallquist

      Oh, even if you agree the laws of physics explain stuff, Craig gets to say, “Aha! Laws of physics! You can’t explain that!”

      • Dunc

        Indeed. Given his position on libertarian free-will, I suspect that he genuinely can’t conceive of anything that doesn’t originate from an agent’s will in some way or another. Turtles all the way down…

        • mnb0

          Thus Craig’s explains everything – hence nothing, as all scientists know.

  • Kevin K

    All theists agree that if there is explanation for the universe, it will be giant interdimensional alien monkeys shitting the universe into existence out of their red monkey butts.

  • eric

    Far more likely WLC is just playing the definition switch game. Use an abstract notion of causa causans with atheists. If/when they agree such a thing exists, imply to a different audience that they agreed about the existence of the theistic Christian God.

    I only have limited anecdotal experience with this, but my impression is that many folks fall into this error. An academic formally argues (i.e. in publications, books etc.) for a concept of God much more limited than the vernacular Christian one, but when making statements to the public they don’t draw a distinction between the God of their proof and their public audience’s concept of God.

    You also see this in fundie political rhetoric. For example, claiming that the reference to ‘the Creator’ in the Declaration of Independence refers to the Christian God when it more correctly refers to Jefferson’s deistic “nature’s God.” That’s another definition switch game.

  • gshelley

    Could he be doing a bait and switch with the word god? Defining god simply as “the cause of the universe” without any attributes or properties, then switching that to his version of god and hoping no one notices?

  • jamessweet

    I really think it’s simpler than all that. Not this “material conditionals” thing, nor the bait-and-switch that other commenters have suggested… rather, I think it all boils down to this:

    Craig knows that most of his audience cannot conceive of a cause for the universe that is not god. Therefore, they will accept this absurd assertion without questioning it, because it seems prima facie plausible to them.

    Simple as that.

    • http://www.facebook.com/chris.hallquist Chris Hallquist

      That’s probably true in a sense. But it’s like Craig has two sets of arguments: the set that works on uninformed audience members, and then the set he can pull out as his REAL arguments when called out on his nonsense by people who know what they’re talking about.

  • http://Skepticali.blogspot.com Skepticali

    I disagree with Craig. If the universe has a cause, it is an infinitely great snack cake.

    • mithrandir

      That’s a big Twinkie.

      • http://Skepticali.blogspot.com Skepticali

        :-D
        I’m obsessed with the idea:

        From a blog post elsewhere…I present to you the Ontological Argument for the Existence of InfiniTwinkie:
          
        1. It is possible that a maximally great snack cake exists.
        2. If it is possible that a maximally great snack cake exists, then a maximally great snack cake exists in some possible world.
        3. If a maximally great snack cake exists in some possible world, then it exists in every possible world.
        4. If a maximally great snack cake exists in every possible world, then it exists in the actual world.
        5. If a maximally great snack cake exists in the actual world, then a maximally great snack cake exists.
        6. Therefore, a maximally great snack cake exists.

        Therefore the universe was created by a Twinkie.

      • http://diaphanus.livejournal.com/ Ian Andreas Miller

        No, it’s the Tiny Timbit.

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