What is an ensemble probability of something that has never occurred and is essentially impossible to model? Have you seen all infinite alternate universes? Probability does not make sense.
Compare the following:
What is the probability that you will die today?
What is the probability that you will die today given that you belong to the category of people with A_i characteristics and whose ensemble probability of dying on a given day has been measured?
Compare the following: What is the probability that you will die today?
What is the probability that you will die today given that you belong to the category of people with A_i characteristics and whose ensemble probability of dying on a given day has been measured?