Title: Finite frequentism explains quantum probability

Abstract: I show that frequentism, as an explanation of probability in classical statistical mechanics, can be extended in a natural way to a decoherent quantum history space, the analogue of a classical phase space. The result is further a form of finite frequentism, in which the Gibbs concept of an infinite ensemble of gases is replaced by the total quantum state expressed in terms of the decoherence basis, as defined by the history space. It is a form of finite and actual frequentism (as opposed to hypothetical frequentism), insofar as all the microstates exist, in keeping with the decoherence-based Everett interpretation, and some versions of pilot-wave theory.