>The Bayesians believe you can look at past results to make good guesses about what will happen in the future. I must be missing something, because I don't unde

>The Bayesians believe you can look at past results to make good guesses about what will happen in the future. I must be missing something, because I don't understand how anyone could disagree, but apparently Karl Popper famously does. Deutsch and Popper disagree with the notion of recording specific "probabilities" as (usually rational) numbers between 0 and 1 for the occurrence of specific future events. This is because the product law for coincidence and the law of the excluded middle lead to a contradiction when you try to do this. Similar arguments have been made elsewhere, e.g.: https://faculty.fuqua.duke.edu/~rnau/definettiwasright.pdf https://faculty.fuqua.duke.edu/~rnau/definettiwasright.pdf Looking at past results to make predictions about what will happen in the future is something everyone does, but that doesn't mean that the means of doing so produces a list of values in [0,1] updated in a very specific way.