Abstract: Physical probability is a measure of the extent to which an event is predetermined by its causes. Statistical probability is a measure of the proportion of events of some kind in a population; I distinguish the proportion in an actual population from the proportion in a hypothetical population (a population that would be generated by a certain process). Inductive probability is a measure of the extent to which one proposition makes another one likely to be true; I distinguish the true measure of this— logical probability, from the best judgement of this that could be produced by a person using correct criteria but with limited abilities —epistemic probability, and from the measure that uses a person's own criteria—subjective probability. Whether or not a belief is rendered probable by its grounds (and so has adequate grounds) varies with the kind of probability being used.

Keywords: adequate grounds, belief, epistemic probability, inductive probability, Keynes, logical probability, physical probability, probability, statistical probability, subjective probability,