In 1819 Leslie, who had been the professor of mathematics at Edinburgh since 1805, resigned the chair when appointed to the more prestigious post of professor of natural philosophy.
Sa 1819 Leslie, na may been ang mga propesor ng matematika at Edinburgh mula noong 1805, ang kalooban ng upuan kapag hihirangin upang angkinin ang mas prestihiyoso-post ng mga propesor ng pilosopiya ng kalikasan.