July 14, 2026

Bayes Theorem with Regard to Vincent Torley

I previously mentioned knowing only one Christian who utilized Bayes and calculated a lower probability for the resurrection of Jesus than before. He went from a 60% probability to 50% to 25% probability. He still believes because after all, it's faith. All other Christians who use Bayes end with their probabilities well into the probability zone, some as high as 95%!

That's what I see. All but one Christian who utilized Bayes comes away with a high probability that Jesus arose from the dead, or that Christianity is true, or that God exists. On the surface Bayes only helps believers confirm their faith. Bayes ought to help believers re-think their faith, but it does no such thing. Granted, not much can change the diehard believer. But my point is that there is something wrong with an allegedly helpful theorem that doesn't force more believers to change their minds [edit: or the minds of non-believers for that matter]. If using Bayes won't help them [edit: or us] why bother?

The Christian believer I mentioned is Vincent Torley. You can read his cogitations on the matter at The Skeptical Zone. Here's his conclusion:
Since my estimate of the total probability of the various Type A skeptical explanations is less than 50%, and since the posterior probability of the Resurrection is much greater than that of the various Type B explanations, belief in the Resurrection is rational, from my perspective.

Based on the evidence, I estimate that there’s about a 60-65% 55-60% chance that Jesus rose from the dead. That means I accept that there’s a 35-40% 45-50% chance that my Christian faith is wrong. [Notice his lowering edits?]

However, I can understand why someone might rate the probabilities of hypotheses 3(a), 3(b) and 3(c) at 20% each, instead of 10%. For such a person, belief in the Resurrection would be irrational, since the total probability of the Type A skeptical hypotheses would exceed 50%.

Summing up: a strong case can be made for the reality of Jesus’ Resurrection. However, a responsible historian would not be justified in asserting that Jesus’ Resurrection is historically certain. As we’ve seen, such a conclusion depends, at the very least, on the claim that there is a significant likelihood that there exists a supernatural Being Who is capable of working miracles, which is something the historian cannot prove. In addition, estimates of the probabilities of rival hypotheses will vary from person to person, and there seems to be no way of deciding whose estimate is the most rational one.
Later, after reading through Michael Alter's book, Resurrection: A Critical Inquiry, Torley came to calculate the probability of the resurrection of Jesus to be 20-25%. LINK But here is the rub that doesn't feel too good. Torley was not prompted to change his mind due to any Bayesian analysis since Alter doesn't use it! Alter merely hammered home a comprehensive evidential case! Checkmate Bayesians!

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