Consensus gentium and double counting

Here’s a way that an atheist could undercut the consensus gentium argument, building on my previous post.

Suppose that views about God or “big gods” came into the world as follows: Brilliant very early thinkers came up with plausible arguments for the existence of God. These arguments may have, for instance, included some selection taken from among cosmological, teleological, moral and religious experience arguments. These arguments were rationally taken up by their followers, but eventually supernaturalistic and maybe even theistic belief was simply passed on by testimony, with the selective advantages of supernaturalism (say, social cohesion effects) helping to keep communities where these beliefs were widespread going.

If this is right, then treating the consensus gentium argument as evidence for theism involves double counting. For the theist presumably also counts the evidential force of arguments like cosmological, teleological, moral and religious experience ones, and since on the above story theism (a) started with one or more of these, and (b) its further spread and persistence can be explained naturalistically quite well by selection effects.

Now, the above argument-focused story may not be plausible to all. But the atheist can make a further move. Dilemma. Either the above story is true or not. If it’s true, then the consensus gentium argument involves double counting. If it’s not true, then likely theism started in some way that is not rational, and then spread and persisted by naturalistic selection effects, and that’s not evidence for theism, either. So, either way, we can dismiss consensus gentium?

What do I say to this? As a theist who is convinced that the other arguments for theism do provide significant evidence, I don’t find it particularly hard to just concede the point.

But there is another move: a merely partial concession. The story about how belief in God is helpful to communities is a plausible story. But it is even more plausible on theism! For on theism, there is an additional probability that God would “go out of his way” and have rational animals exist in conditions where belief in God is helpful, precisely as a means to making belief in God persist and spread naturally. Thus, widespread of theistic belief may be probable on naturalism, but on theism is even more so. This may not be strong evidence for theism (the Bayes ratio can’t exceed 2, which is “substantial” but not “strong” on Jeffreys’ scale), but is still some evidence.