scotpens wrote:
Lindley wrote:
I think it's fairly obvious that p(biosphere  habitable zone) > p(biosphere  !habitable zone).

Could you please explain that formula in layman's language? I never got any higher in math than firstyear algebra.

The probability of a biosphere given that a planet is in the habitable zone is greater than the probability of a biosphere given that a planet is not in the habitable zone.
This does not say a biosphere is likely, just that it's
more likely by a nonzero amount.