Political economy originally was the term for studying production, buying, and selling, and their relations with law, custom, and government, as well as with the distribution of national income and wealth. Political economy originated in moral philosophy. It developed in the 18th century as the study of the economies of states, polities, hence the term political economy.In the late 19th century, the term economics came to replace political economy, coinciding with publication of an influential textbook by Alfred Marshall in 1890. Earlier, William Stanley Jevons, a proponent of mathematical methods applied to the subject, advocated economics for brevity and with the hope of the term becoming "the recognised name of a science."