Bob’s reply is not concerned with the truth of whether X did Y in the Bayesian sense. Bob doesn’t argue about what the correct probability happens to be.
It’s concerned with dispute resolution. In a discussion about truth, wanting doesn’t matter. In a process of dispute resolution it matters a great deal.
Not generally but I notice that the argument I cited is usually invoked when there is a dispute, e.g.:
Alice: “I have strong doubts about whether X really did Y because of...”
Bob: “But X already admitted to Y, what more could you want?”
Bob’s reply is not concerned with the truth of whether X did Y in the Bayesian sense. Bob doesn’t argue about what the correct probability happens to be.
It’s concerned with dispute resolution. In a discussion about truth, wanting doesn’t matter. In a process of dispute resolution it matters a great deal.