The probabilities for life in different galaxies aren’t independent if you’re uncertain about the fraction of stars/galaxies that spawn life. You could think that with p=.5 life is super-rare and with p=.5 life is super-common; then you’d put .5 on both questions.
The probabilities for life in different galaxies aren’t independent if you’re uncertain about the fraction of stars/galaxies that spawn life. You could think that with p=.5 life is super-rare and with p=.5 life is super-common; then you’d put .5 on both questions.