My probability of ending up the original couldn’t have been 0.5^99, that’s effectively impossible, less than the probability of hallucinating this whole conversation.
Does anyone have a sense of what the lower limit is on meaningful probability estimates for individual anticipation? Right, like there should be some probability p(E) where, upon experiencing E, even a relatively sane and well-balanced person ought to predict that the actual state of the world is ~E, because p(I’m Crazy or I’ve Misunderstood) >> p(E).
More to the point, p(E) should be roughly constant across apparently sane people; I would guess that the probability of hallucination doesn’t vary by much more than a factor of 10 among people who have no reason to expect that they are hallucinating. 10^1 might be small relative to whatever the Minimum Probability turns out to be.
Morendil, my guess is that you don’t question whether having a car is the “normal” choice, either, but you have started to question whether it’s the efficient choice. Most people don’t evaluate the economic efficiency of owning a car precisely because everyone agrees that it’s normal to own a car, and people often just do what they see as normal without stopping to think about it.
Incidentally, zipcar.com, an hourly car rental service, sometimes runs ads that break down the cost of using a Zipcar for your driving needs on an annual basis vs. the cost of owning a car. I checked the math on one of those ads and found it persuasive; I’ve been using Zipcar for 3 years now and have never felt the need to own a car.