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DragonGod comments on P: 0 <= P <= 1 - Less Wrong Discussion

5 Post author: DragonGod 27 August 2017 09:57PM

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Comment author: Vaniver 29 August 2017 03:50:38PM 0 points [-]

Consider the logical proposition "A xor".

Does it makes sense to call it true or false? Not really; when I try to call it a proposition the response should be "type error; that's a string that doesn't parse into a proposition."

Ah, but what probability do we assign to the statement "<A xor> results in a type error because it's a string that doesn't parse into a proposition"? 1-epsilon, and we're done. Remember, the probabilistic model of utility came from somewhere, and has an associated level of evidence and support. It's not impossible to convince me that it's wrong.

But does this make me vulnerable to Pascal's mugging? However low I make epsilon, surely infinity is larger. It does not, because of the difference between inside-model probabilities and outside-model probabilities.

Suppose I am presented with a dilemma. Various different strategies all propose different actions; the alphabetical strategy claims I should pick the first option, the utility-maximizing strategy claims I should pick the option with highest EV, the satisficing strategy claims I should pick any option that's 'good enough', and so on. But the epsilon chance that the utility is in fact infinite is not within the utility-maximizing strategy; it refers to a case where the utility-maximizing strategy's assumptions are broken, and thus needs to be handled by a different strategy--presumably one that doesn't immediately choke on infinities!

Comment author: DragonGod 12 September 2017 08:39:12PM 0 points [-]

I understand your argument about breaking the assumptions of the strategy. What does inside model probabilities and outside model probabilities mean? I don't want to blindly guessing.

Comment author: Vaniver 13 September 2017 06:52:16PM 0 points [-]

See here.