Book excerpt: First published in 1994. Concepts of probability are an integral component of economic theory. However there are a wide range of theories of probability and these are manifested in different approaches to economic theory itself. In this book Charles McCann, Jr provides a clear and informative survey of the area which serves to standardize terminology and so integrate probability into a discussion of the foundations of economic theory. This is illustrated by examples from Austrian, Keynesian and New Classical Economics.