  Professor Sir Karl Popper (1902-1994) was one of the most influential
philosophers of science of the twentieth century, best known for his doctrine
of falsifiability. His axiomatic formulation of probability, however, is
unknown to current scientists, though it is championed by several current
philosophers of science as superior to the familiar version. Applying his
system to problems identified by himself and his supporters, it is shown that
it does not have some features he intended and does not solve the problems they
have identified.
