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0 pointslupire3y ago0 comments

Probability is weight/count of cases of interest divided by weight/count of all possible cases.

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4 comments · 2 top-level

quickthrower23y ago· 2 in thread

I just rolled a 6 sided die here and looked at the outcome. For you the probability it is a 6 is 1/6. For me is isn’t 1/6. Same object!

deltasevennine3y ago

For you it isn't 1/6 but for him it is. From your perspective can you derive from the knowledge you have why that for him the probability is 1/6?

And I mean derive as in derive the mathematical probability from all your knowledge about physics and the dice to explain why the lack of knowledge appears to him as a probability.

This is the essence of my question. We assume it. Probability is taken to be true for no reason, similar to how we just assume logic to be true.

quickthrower23y ago

Probability is an abstract concept so if he has a really good model of the universe there is no reason he couldn’t have better information.

We don’t really know if “god plays dice” so to speak. We probably will never fully understand the underlying fabric of the universe even with lots of theories and experiments.

It is like we get to run valgrind on the program but never see the source code.

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mturmon3y ago

Perhaps you're just kidding around, but of course that's not good enough for a definition.

It doesn't handle continuous random quantities. It doesn't even handle situations with a discrete outcome but where counting the possible cases isn't well-defined (Buffon's needle being one, but an even better one being the chance of a tossed thumbtack landing point-up). It also doesn't handle cases where symmetry or physics can give the answer, but you can't count cases because they aren't finite or aren't necessarily a-priori equiprobable.

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