Yeah, this article seems overly harsh on the "restrainists." After all, their assumption could have started from the empirical observation that many species have reproductive strategies that do not emphasize "as many as possible." Humans, elephants, and Lions have few offspring per reproductive cycle relative to spiders and frogs. Clearly SOMETHING is restraining their reproductive rate and promoting a high investment strategy.

Even so, it was probably very improbable, considered in an isolated event—but it only had to happen once, and there were a lot of tide pools.

isn't it more likely that the "first replicator" was not a single event, but that it started multiple times and failed to survive in the vast majority of cases?

You forgot about MetaOmega, who gives you $10,000 if and only if No-mega wouldn't have given you anything, and O-mega, who kills your family unless you're an Alphabetic Decision Theorist. This comment doesn't seem specifically anti-UDT -- after all, Omega and No-mega are approximately equally likely to exist; a ratio of 1:1 if not an actual p of .5 -- but it still has the ring of Just Cheating. Admittedly, I don't have any formal way of telling the difference between decision problems that feel more or less legitimate, but I think part of the answer might be that the Counterfactual Mugging isn't really about how to act around superintelligences: It illustrates a more general need to condition our decisions based on counterfactuals, and as EY pointed out, UDT still wins the No-mega problem if you know about No-mega, so whether or not we should subscribe to some decision theory isn't all that dependent on which superintelligences we encounter.

I'm necroing pretty hard and might be assuming too much about what Caspian originally meant, so the above is more me working this out for myself than anything else. But if anyone can explain why the No-mega problem feels like cheating to me, that would be appreciated.