Philosopher, born at Ardchattan, Argyllshire; after a university training at Edinburgh and Glasgow he entered the Free Church; was for a brief term Free Church minister of Cramond, from which he was transferred to a chair in the Free Church College, but in 1856 succeeded Sir William Hamilton as professor of Logic and Metaphysics at Edinburgh, a position he held till 1891, when he resigned; his writings include the standard edition of Berkeley, with notes and a life, monographs on Locke and Berkeley in the series of "Philosophical Classics," and two vols. on the "Philosophy of Theism," being the Gifford Lectures delivered 1895-96; b . 1819.