I reported a 1% chance of extra-Earth sentient aliens in our galaxy, on Yvain’s survey. Is that overconfident? I was reasoning that, if the rest of the universe is real (which it may not be under some simulation hypotheses), the odds of there being extra-Earth intelligence in this particular time-window, which has already acquired sentience and has not yet become lightcone-tiling or made itself extinct, was rather small. (The galaxy is about 100,000 light-years across).
Now that I write this, I’m inclined to think I didn’t pay enough heed to uncertainty in whether I set up the analysis correctly or was missing a major consideration.
I meant the people who reported 99% chances, mostly. The Fermi paradox is probably good info.
One thing I do worry about is if some anthropic idea (self-indication principle) may favor densely populated universes over sparsely populated universes. Something like that is true in this model, but I’m not sure it could work (probability of intelligent life is a matter of logical necessity, what other implications do you get if you apply this model of anthropic reasoning to uncertain logical necessities?) and even if it does it should only imply a serious probability for aliens in the observable universe, not the galaxy.
Maybe other people think they have good info.
But they don’t in fact have good info, so there must (with very high probability) have been some sort of rationality blunder involved.
I reported a 1% chance of extra-Earth sentient aliens in our galaxy, on Yvain’s survey. Is that overconfident? I was reasoning that, if the rest of the universe is real (which it may not be under some simulation hypotheses), the odds of there being extra-Earth intelligence in this particular time-window, which has already acquired sentience and has not yet become lightcone-tiling or made itself extinct, was rather small. (The galaxy is about 100,000 light-years across).
Now that I write this, I’m inclined to think I didn’t pay enough heed to uncertainty in whether I set up the analysis correctly or was missing a major consideration.
I meant the people who reported 99% chances, mostly. The Fermi paradox is probably good info.
One thing I do worry about is if some anthropic idea (self-indication principle) may favor densely populated universes over sparsely populated universes. Something like that is true in this model, but I’m not sure it could work (probability of intelligent life is a matter of logical necessity, what other implications do you get if you apply this model of anthropic reasoning to uncertain logical necessities?) and even if it does it should only imply a serious probability for aliens in the observable universe, not the galaxy.