suppose that you live on average 80 years. [...] 80.01 years [...] 79.99 years
I started writing a completely wrong response to this, and it seems worth mentioning for the benefit of anyone else whose brain has the same bugs as mine.
I was going to propose replacing "Compute how many times you expect this to happen to you; treat it as normal if n>=1 and ignore completely if n= 1, ignore completely if n<0.01, and interpolate smoothly between those for intermediate n".
But all this does, if the (dis)utility of the event is hugely greater than that of everything else you care about, is to push the threshold where you jump between "ignore everything except this" and "ignore this" further out, maybe from "once per 80 years" to "once per 8000 years".
I fear we really do need something like bounded utility to make that problem go away.
I fear we really do need something like bounded utility to make that problem go away.
If what you dislike is a discontinuity, you still get a discontinuity at the bound.
I am not a utilitarian, but I would look for a way to deal with the issue at the meta level. Why would you believe the bet that Pascal's Mugger offers you?
At a more prosaic level (e.g. seat belts) this looks to be a simple matter of risk tolerance and not that much of a problem.
Summary: the problem with Pascal's Mugging arguments is that, intuitively, some probabilities are just too small to care about. There might be a principled reason for ignoring some probabilities, namely that they violate an implicit assumption behind expected utility theory. This suggests a possible approach for formally defining a "probability small enough to ignore", though there's still a bit of arbitrariness in it.