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Rolf_Nelson2 comments on Probability is in the Mind - Less Wrong

60 Post author: Eliezer_Yudkowsky 12 March 2008 04:08AM

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Comment author: Rolf_Nelson2 14 March 2008 03:38:00AM 0 points [-]

if the vast majority of the measure of possible worlds given Bob's knowledge is in worlds where he loses, he's objectively wrong.

That's a self-consistent system, it just seems to me more useful and intuitive to say that:

"P" is true => P
"Bob believes P" is true => Bob believes P

but not

"Bob's belief in P" is true => ...er, what exactly?

Also, I frequently need to attach probabilities to facts, where probability goes from [0,1] (or, in Eliezer's formulation, (-inf, inf)). But it's rare for me to have to any reason to attach probabilities to probabilities. On the flip side, I attach scoring rules in the range [0, -inf] to probability calculations, but not to facts. So in my current worldview, facts and probabilities are tentatively "made of different substances".