A Scotch philosopher and historian, born at Logierait, Perthshire; after passing through the universities of St. Andrews and Edinburgh, he in 1745 was appointed Gaelic chaplain to the Black Watch Highland Regiment, and was present at the battle of Fontenoy; in 1757 he became keeper of the Advocates' Library in Edinburgh; two years later professor of Natural Philosophy, and subsequently of Moral Philosophy in the university there; during his professorship he, as secretary, was attached to the commission sent out by Lord North to bring about a friendly settlement of the dispute pending between England and the North American colonies; resigning his chair in 1785 he retired to Neidpath Castle, to engage in farming at Hallyards, an estate in the same neighbourhood; died at St. Andrews; his best-known works are "Institutes of Moral Philosophy," "History of the Roman Republic," and "Principles of Moral and Political Science" (1723-1816).