(Or to say that in a more mathy way, say we started with a .4 chance of a young man being a conformist, a .6 chance for a young man to be wearing earrings, and a .9 chance for the conformists to be wearing earrings. Then we'd calculate (0.9 * 0.4) / (0.6) and get a 0.6 chance for the man in question to be conformist. We don't have exact numbers like these in our heads, of course, but we do have a rough idea.)

Love this example. I have been a HPMOR fan and a LWer for a while now, but i'm just taking my first steps into solid bayesian reasoning. Just out of curiosity the 0.6 probability assigned, includes "conformists" and "non-conformists" right? I think i'm pretty much right, but just feel that I need some validation to make sure I havent completely misunderstood what's going on.