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Comment by gradus_ad | Hacker News Reader

For life to emerge in the span of a few million years within liquid interiors of early solar system bodies, life would need to be a relatively high probability event. I don't think this changes the probability of life calculus vs the traditional life emerging on Earth story.

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No, that's wrong. You're ignoring that if it didn't happen, we wouldn't be here to see the result. Observer selection bias. The less common OoL is, the more biased our observation is.

Observer selection bias is independent of the earth vs non earth body question, it's an issue regardless.

Yes, it also demolishes the naïve Copernican argument that because life is on Earth, it must be common.

The more subtle argument was that because life originated early on Earth, OoL must be a high probability event. But that argument implicitly assumes the probability of OoL is relatively constant with time, so it wouldn't be biased to occur early. OoL on small planetesimals is naturally biased to occur early, due to decay of those short lived radioisotopes. After the planetesimals freeze OoL there doesn't seem possible.

Ok. What is an Ool?

Watch the movie Caveman to find out! Ool anyone?

In this context "Origins of life"

I would suggest replacing 'Ool' by 'origin of life' or even better just 'life' then. Is much easier to understand and it just adds one character to the term

I would think this point would be obvious, but apparently not given the many frustrating discussions I’ve had with smart people on the topic. (Maybe there is a subtlety I’m not appreciating?) It’s a relief to see the good solid sense in all your comments on this thread.

If there were enough of these warm, water-bearing bodies, then the probability could be low and still result in early life formation, right?

Especially if the "enough" is "enough around any star, anywhere". The a priori probability of it happening around any particular star need not be high. And "anywhere" can be something extremely broad, as in "on any branch of a universal Many Worlds wave function".

Yes but the window of time during which these bodies could have contained liquid water was very narrow, so there would have needed to be a very high number of such bodies to support the low probability of life hypothesis

Unless life can only appear on that kind of environment for some reason.

It's hard to imagine any such reason. Honestly I don't think there's any to find. But it's still an open question.

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