Less Wrong is a community blog devoted to refining the art of human rationality. Please visit our About page for more information.

Eliezer_Yudkowsky comments on Conservation of Expected Evidence - Less Wrong

68 Post author: Eliezer_Yudkowsky 13 August 2007 03:55PM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Comments (77)

Sort By: Old

You are viewing a single comment's thread.

Comment author: Eliezer_Yudkowsky 17 August 2007 04:45:24PM 14 points [-]

...

Barkley, you don't realize that Bayes's Theorem is precisely what describes the normative update in beliefs over time? That this is the whole point of Bayes's Theorem?

Before black swans were observed, no one expected to encounter a black swan, and everyone expected to encounter another white swan on occasion. A black swan is huge evidence against, a white swan is tiny additional evidence for. Had they been normative, the two quantities would have balanced exactly.

I'm not sure what to say here. Maybe point to Probability Theory: The Logic of Science or A Technical Explanation of Technical Explanation? I don't know where this misunderstanding is coming from, but I'm learning a valuable lesson in how much Bayesian algebra someone can know without realizing which material phenomena it describes.