James Thomson's first contact with Newtonian philosophy was as a student at the University of Edinburgh between 1715 and 1725. Newtonianism had been first introduced there by David Gregory, who, upon graduation in 1683, was appointed Professor of Mathematics. William Whiston, Newton's successor at Cambridge, says that it was to one of Gregory's papers that he owed his conversion to Newton's philosophy. When David Gregory accepted the Savilian professorship of astronomy at Oxford in 1691, he was succeeded at Edinburgh by his brother, James Gregory, another Newtonian. In 1725, on the recommendation of Newton himself, Colin Maclaurin was appointed to assist James Gregory at Edinburgh; thus, from 1683 on, Newtonianism was firmly established in the University of Edinburgh.