Debates about religion and physics are annoying because usually, no one has any idea what they’re talking about. Actually, this is true of all “religion and [science X]” debates where X is not psychology or evolutionary biology, because these are the only sciences for which half-decent popularizations are available. And, while unlike most people I can claim to know something about things like chemistry and neuroscience, I know basically nothing about most of the ideas in physics that ordinary people care about.
Thus, I get really uncomfortable when I read things like this post by Jim Manzi, which purports to say something worthwhile about the fine-tuning argument for the existence of God (the claim that we need God to explain why the laws of physics are [so the argument goes] “fine-tuned” for life). It’s clear Manzi doesn’t know much at all about the subject, but should I comment given that I don’t either? Well, actually, even without knowing the details of the science a few things are obvious.
1) Unlike most religious people who write about this issue, Manzi seems to recognize that there is no reason to prefer the God hypothesis to the multiverse hypothesis. You cannot ccomplain about the untestability of the multiverse hypothesis unless you have some proposal to test the God hypothesis. You cannot complain about the lack of evidence for the multiverse hypothesis unless you have evidence for the God hypothesis beyond the mere possibility of explaining something the multiverse hypothesis also explains.
2) In spite of this, Manzi seems to think that atheists are somehow in trouble on this one, because (Manzi claims) there is no reason to prefer the multiverse hypothesis to God. Huh? Believers are the ones claiming there’s an argument for God here, atheists tend to not care aside from that fact. No one is claiming there’s a proof of atheism here.
3) Both of the articles Manzi links to make clear that scientists have other reasons for liking the multiverse hypothesis, other than that it’s an alternative to God. When William Lane Craig runs around saying that the multiverse is a desperate attempt to avoid God, he’s bluffing, to put it politely.
4) Manzi seems oblivious to the above, even though he quotes a relevant part of one of the articles. What’s up with that? He rationalizes it all by declaring the multiverse a “metaphysical” idea, and therefore no scientific investigation can possibly be relevant to it. This is the same rather daft mistake made by people who think science cannot tell us anything about knowledge–using a bit of jargon (metaphysics) in order to pretend that a controversial claim is true by definition.
5) He makes the mistake of thinking that if something is unobservable, it is beyond scientific investigation. But obviously, something can be beyond direct observation and yet still have effects that scientists can observe.