It might be worth considering a mixed or hybrid path -- if you can get a high-paying traditional (software, finance, etc.) job, while being very frugal and saving money (and you don't have much or any debt), you can get pretty quickly to the point of having a very comfortable savings buffer. If at that point you use your savings for living frugally, but not for funding your startups (do that with Other People's Money), I think you'll have more runway and more options than you might otherwise, and should you find that the startup life is not working out you should have a good backup trajectory available where you go back to a high-paying traditional career and retire.

I'm curious why you think (4) seems unlikely -- is this a fact about your personality, or about the world (i.e. you think there will be no normal-ish jobs, and/or the world will not survive to see your retirement?) Considering again high-paying jobs like software and finance, I think the math shows that a very frugal person can effectively retire after very few years in such a job -- perhaps as little as a decade, certainly as little as two, which is similar to your stated startup timeframe -- depending on what your goals are. And once you're in "effective retirement" (i.e. you don't have a problem supporting yourself), then you're in a great position to try to get a startup going.

"Baba Yaga and her 52 apprentices"? That's possible, but I'm not actually sure how this can become a battle because the obvious move is for Riddle to "bombarda" his own skull.

I'm thinking we are going to get some more talking. And it is pretty likely we are about to have explained to us how he already lost...

Wait. Are we at all sure the Tom's are still outside the mirror? If the plan was to trap Voldemort in the mirror, how do we know that didn't already happen, and this is years later when they finally finished tracking down the horcruxes? Because the best mirror-plane prison would be one with no passage of time in it.

This also fits the prophecy, because in this case, Harry did defeat him, by being willing to go down with him. Which is a power he knows not.

Another part of coherence is that, for groups, it's supposed to reconcile differing viewpoints - to only act on what's shared.

My son's teacher creates special projects for him to work on to better challenge him. I very much don't want that to stop.

I like these things, and I've added myself, but... there've been similar ones in the past, they don't stay up to date. I feel like without some way for users to know, six months from now, that the information they're looking at is still accurate, any given iteration is never going to be very useful for long.

An idea that's floating around in my head, I think I've mentioned it before, is that a service like this could require everyone to occasionally confirm that they're still in the same place. Send out an email once a month, they can click a link or reply to remain on the map, or ignore it to be removed.

If possible, I think it would be nice if the digest contained at least an excerpt from the beginning of the posts/comments in question, in addition to the link.

I don't see a dilution of that magnitude as a problem when the material is the core material of the site. It wouldn't be obviously silly to have this as a lasting feature of the site, and start again when we finally finish.

The most plausible pattern for that one is exclusive or; an element is only in the third item if it is in exactly one of the preceding two items.

As several people have asked about my intentions in posing these problems, I'll answer here.

What I was interested in was seeing how people deal with extreme probabilities.

Some people have in the past expressed the view on LW that it is not humanly possible to be justifiably 80 decibans sure of anything. You would have to able to be right about it with an error rate of no more than 1 in 100 million. Who can be right that often about anything? Surely, some would say, it must remain more likely that you're dreaming, or hypnotised, or being trolled by the Matrix Lords, or something else that you haven't even thought of, for who can scour out every last hundred millionth of possibility space? And yet, ordinary people, who have never learned to believe that it is impossible, have no difficulty in collecting the Euromillions jackpot, which has approximately those odds against. If they are as sure afterwards that they have won as they would have been sure before that they would not, that's a swing of 160 decibans.

BTW, that was the lottery I had in mind in composing the example, and is not a fly-by-night operation. I might have sharpened the example by adding that. Someone wins the Euromillions jackpot every few weeks, for a prize of 10 to above 100 million pounds, depending on how many weeks it has rolled over.

The current consensus in the comments, though, is that the evidence of the house keys is strong enough that the posterior certainty that I have them is not perceptibly swayed by methodological flaws gross enough to completely discredit any paper that relied on statistical techniques to support its claims, and that I can be justifiably sure I have won the lottery at least by the time my bank confirms receipt of the money. These are my own views too.

"0 and 1 are not probabilities", people still say here from time to time, yet a lot of everyday life runs well enough on 0s and 1s.

I think I might summarize the lesson here (at least from part 1) as "strong enough evidence covereth a multitude of sins", but I'd like to hear the poster's thoughts as to what the lesson is meant to be.