We’re speaking here not of Bayesianism as a religion but of the use of Bayesian inference to assess or validate the evidence regarding religious belief, in short, the probability that God !=0 or the probability that the Pope is Catholic or, as Tyler Cowen put it, the probability that Lutheranism is true.
As a statistician and social scientist I have a problem with these formulations in large part because the states in question do not seem at all clearly defined—for instance, Lutheranism is a set of practices as much as it is a set of doctrines, and what does it mean for a practice to be “true”; also the doctrines themselves are vague enough that it seems pretty much meaningless to declare them true or false.
Nonetheless, people have wrestled with these issues, and it may be that something can be learned from such explorations.
So the following email from political philosopher Kevin Vallier might be of interest, following up on my above-linked reply to Cowen. Here’s Vallier:
Philosophers of religion have been using Bayesian reasoning to determine the rationality of theistic belief in particular for many years. Richard Swinburne introduced Bayesian analysis in his many books defending the rationality of theistic and Christian belief. But many others, theist and atheist, use it as well. So there actually are folks out there who think about their religious commitments in Bayesian terms, just not very many of us. But I bet there are at least 1000 philosophers, theologians, and lay apologists who find thinking in Bayesian terms useful on religious matters and debates. A nice, accessible use of Bayesian reasoning with regard to religious belief is Richard Swinburne’s The Existence of God, 2nd ed.
Wow—I had no idea there were 1000 philosophers in the world, period. Learn something new every day.
In all seriousness . . . As indicated in my post replying to Cowen, I’m interested in the topic not so much out of an interest in religion but rather because of the analogy to political and social affiliation. It seems to me that many affiliations are nominally about adherence to doctrine but actually are more about belonging. This idea is commonplace (for example, when people speak of political “tribes”), but complications start to arise when the doctrines have real-world implications, as in our current environment of political polarization.