Dissolving the Fermi Paradox, and what reflection it provides

If asked to bet about the probability of alien life (with payoffs measured in pleasure rather than dollars), most people would recommend making an anthropic update. That implies a much more likely future filter, as Katja has argued, and the best guess is then that we are in a universe with large amounts of life, and that we are overwhelmingly likely to soon die.

(Of course, taking this line of argument to its extreme, we are even more likely to be in a simulation.)

Action-wise, the main upshot is that we ought to be much more interested in averting apparently-insurmountable local risks than we otherwise would be. For example, one might be tempted to simply write off worlds in which there are incredibly potent information hazards that almost always end civilizations at a certain stage of development, since that seems like a hopeless situation. But the anthropic update suggests that such situations contain so many observers like us that it can roughly cancel out the hopelessness.

More precisely, the great filter argument suggests that increasing your survival probability by 10% in doomed worlds is actually very good, same order of magnitude as decreasing risk by 10% in a "normal" world with doom probabilities <50%.

(The importance of coping with nearly-certain doom still depends on the probability that we assign to settings of background variables implying nearly-certain doom. That probability seems quite low to me, since it's easy to imagine worlds like ours with strong enough world government that they could cope with almost arbitrary technological risks.)

I’m not sure I understand why they’re against point estimates. As long as the points match the mean of our estimates for the variables, then the points multiplied should match the expected value of the distribution.

Removed from the frontpage for now, since we try to keep frontpage discussion free from being primarily about the rationality community and it's specific structure. I would recommend putting the last section into its own post, which is then on your personal blog, and then I am happy to promote this to the frontpage.

Possibility-if panspermia is correct (the theory that life is much older than Earth and has been seeded on many planets by meteorite impacts), then we might not expect to see other civilizations advanced enough to be visible yet. If evolving from the first life to roughly human levels takes around the current lifetime of the universe, rather than of the Earth, not observing extraterrestrial life shouldn't be surprising! Perhaps the strongest evidence for this is that the number of codons in observed genomes over time (including as far back as the Paleozoic) increases on a fairly steady logarithmic trend, which extrapolates back to shortly after the birth of the universe.