Good points. However: (1) Most of the cataclysms we see are either fairly explicable (supernovae) or seem to occur only at remote points in spacetime, early in the evolution of the universe, when the emergence of intelligent life would have been very unlikely. Quasars and gamma ray bursts cannot plausibly be industrial accidents in my opinion, and supernovae need not be industrial accidents.
(2)Possible, but I can still imagine large civilizations of people whose utility function is weighted such that "99.9999% death plus 0.0001% superman" is inferior to "continued mortal existence."
(3)Again possible, but there will be a selection effect over time. Eventually, the remaining people (who, you will notice, live in a universe where people who try to ascend to godhood always die) will no longer think ascending to godhood is a good idea. Maybe the ancients were right and there really is a small chance that the ascent process works and doesn't kill you, but you have never seen it work, and you have seen your civilization nearly exterminated by the power-hungry fools who tried it the last ten times.
At what point do you decide that it's more likely that the ancients did the math wrong and the procedure just flat out does not work?
(4)The minority might have no problems with risks that do not have a track record of killing everybody. However, you have a point: a rational civilization that expects the galaxy to be heavily populated might be well advised to hide.
(2)Possible, but I can still imagine large civilizations of people whose utility function is weighted such that "99.9999% death plus 0.0001% superman" is inferior to "continued mortal existence."
You have to keep in mind that subjective experience will be 100% superman. The whole idea is that the MWI is true and completely convincingly demonstrated by other means as well. It is like if someone would tell you: you enter this room and all you will experience is that you leave the room with one billion dollars. I think it is a seducing pros...
We have a sample of one modern human civilization, but there are some hints on how likely it was to happen.
Major types of hints are:
Data for:
Data against:
To me it looks like life, animals with nervous systems, Upper Paleolithic-style Homo, language, and behavioral modernity were all extremely unlikely events (notice how far ago they are - vaguely ~3.5bln, ~600mln, ~3mln, ~200k or ~600k, ~50k years ago) - except perhaps language and behavioral modernity might have been linked with each other, if language was relatively late (Homo sapiens only) and behavioral modernity more gradual (and its apparent suddenness is an artifact). Once we have behavioral modernity, modern civilization seems almost inevitable. Your interpretation might vary of course, but at least now you have a lot of data to argue for your position, in convenient format.