Richard, you see, has, um, --well it is best to use his own words:
"In fact, I show how the fine tuning of the physical constants actually proves God doesn’t exist. Quite conclusively in fact."
Quite conclusively? Really?
This is of course complete nonsense, which I pointed out on his blog. He has threatened to treat my comments as spam because I haven't actually read his chapter in some book that contains this "proof." I have read other such proofs, such as from Ikeda and Jefferys. I know exactly how they work.
I wonder if Carrier agrees with many of his FTB colleagues who argue that it is OK for Dawkins to criticize absurd theological arguments without actually studying them? Because I am using the same argument against him--I don't have to read his chapter to recognize it as utter nonsense. Can you say "Courtier's Reply?"
Now one can argue that under the assumptions of fine-tuning (the habitability of the universe is sensitive to the constants) and a low probability of the constants (something which nobody actually knows--but you can assume it for the sake of an argument) that multiverse explanations are more plausible, from an Occam's Razor sense, than supernatural design. But even then neither Carrier nor anyone else can prove "quite conclusively" that God doesn't exist. Total Kool-Aid. And he doesn't need Bayes' theorem--which if you don't know is a simple theorem in probability that freshmen learn--but like Heisenberg's Uncertainty Principle is disgustingly abused in the hands of the intellectually challenged/dishonest and the mathematically illiterate.
In this kind of argument, Bayes' Theorem--which is incredibly powerful when used properly--is merely obfuscatory, in a Sokal-like sense.
So... let's image an incredibly fine-tuned universe:
1. This universe has only one physical constant, C.
2. The universe is only habitable if C is within its measured value by one part in 1023.
3. The laws of this universe predict the value of C.
Now here is an extremely fine-tuned universe! I challenge Carrier to prove that such a universe precludes the existence of a god.
If you believe he can, there may be a lidless eye award in your future!