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Comment by cwp | Hacker News Reader

No. That's like flipping a coin and then saying the probability of getting heads is 1. The fact that something happened is not proof that it was guaranteed to happen.

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Re-read what the GP claimed. Given the initial conditions of the universe, the probability it might eventually lead to my own existence may well be infinitessimal, but in the context of the probability of me winning the lottery (for example), my existence is already a given.

No, what he was saying was that the probability of you winning the lottery is quite high compared to the probability of you existing in the first place. His point was that mathematicians sometimes try to contextualize these very low probability scenarios so that lay-people don't collapse them all into a single "basically impossible" bucket. They're not wrong, but it's not a useful way to think about whether buying a lottery ticket is a good idea.

I'll quote: "the probability of you winning the lottery is 10000000000000x more favorable than the probability of you existing in this universe". That statement is categorically wrong. If you're going to consider the probability of my ever coming to existence in the first place, you need to count it as part of the probability of winning the lottery too. If it had said "the probability of anybody winning" I would've cut it some slack (though the probability that a universe might develop with sentient beings capable of inventing lotteries is still a prerequisite in both cases).

> I'll quote: "the probability of you winning the lottery is 10000000000000x more favorable than the probability of you existing in this universe". That statement is categorically wrong.

Yup -- it was written in a universe where the poster they replied to exists, so that probability is = 1 here.

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