By the early 1880s it is clear his competence had expanded to the full spectrum of the mathematical sciences: Fourier's theory of heat, Poisson's mechanics, Cournot, Gossen, Jevons and Walras on mathematical economics, Airy, Thomson and Tait, and Clerk Maxwell on physics, and, above all, Laplace on the theory of probability.

Statistics on the Table: The History of Statistical Concepts and Methods. Harvard University Press. p. 91