Abstract John Crossley settled in Australia 1968 having been a graduate student and later University Lecturer at Oxford. This is brief account of his logical career. It revised version webcast talk for World Logic Day on 14 January 2022.

This paper examines critically the contributions of Cournot, Jevons and Walras as the founders of classical mathematical economics from a methodological standpoint. Advances in different economic schools and doctrines in the 19th century produced an environment of multi-dimensionality in economic analysis which was regarded by the pioneers of classical mathematical economists as a chaotic state...