[wbhart]

This is an important computation. It's even scarier if you suppose that you are not in any way special. It is likely that you are not one of the first 5% of humans to ever live. Thus, given that such a great proportions of all humans who have every lived are alive now, the implication is that the human race hasn't got long to go even if the population remains constant! Or you could just assume you are special.

[jodrellblank]

By that calculation, no human should assume they are in the last 5% so the human race is immortal.

It sounds like nonsense; the people actually in the first 1% are not more special than the people in the 43rd 1%, but you have to be somewhere in the distribution.

No point is special in the sense that you have a stronger than usual reason to assume you aren't there and are more likely elsewhere.

[wbhart]

Not really. You shouldn't assume you are in the last 5%. Statistically, by definition, it is most likely (though not certain) that you are not.

[jodrellblank]

That's the sort of analysis I'm questioning - it's also 95% likely that I'm not in the second-last 5%, and the same for the third-last 5% and for any 5% slice.

How can we usefully reason anything from a start like that?