Irish idealist. Born at Kilkenny in Ireland, Berkeley entered Trinity College, Dublin in 1700. In 1707 he became a Fellow of the College and two years later published An Essay towards a New Theory of Vision (his Philosophical Commentaries were unpublished notes of the years before 1709). This was followed by the first (and only extant) part of A Treatise concerning the Principles of Human Knowledge (1710) and the Three Dialogues between Hylas and Philonous (1713), which was an attempt to explain the doctrines of the earlier work in a more readily understood form. Berkeley moved to London and spent much of the next decade travelling in France and Italy. However, the fact that he was in London in 1715 seems to disprove the story that it was a fit of apoplexy, brought on by arguing with Berkeley, that carried off the philosopher Malebranche. In 1721 Berkeley published De Motu (‘On Motion’) attacking Newton's philosophy of space, a topic he returned to much later in The Analyst of 1734. In 1724 he entered with enthusiasm on a project for founding a College in Bermuda, for the Christian education of both colonial and indigenous people of America. With his new wife he set sail westward in 1728, arriving and settling in Rhode Island. While there he corresponded with the American philosopher Samuel Johnson, and wrote Alciphron, which was eventually published in 1732. Government support promised for his educational project never materialized, and Berkeley returned to London in 1732, and was made Bishop of Cloyne in 1734. Thenceforth his publications concerned the well-being of the people of his diocese, although Siris (1744) contains discussions of the philosophy of nature, as is promised by its full title (A Chain of Philosophical Reflexions and Inquiries concerning the Virtues of Tar-Water, and divers other subject connected together and arising from one another). He died in Oxford.
Berkeley is notorious for his immaterialism, or apparent denial of the reality of any external world, with the consequent shrinking of reality down to a world of minds and their own sensations or ‘ideas’. The theme of the impossibility of ‘inert senseless matter’, and the merits of a scheme based on a pervading, all-wise providence whose production is the conceptual world, the world of ideas, that make up our lives, runs through all Berkeley's writing. What he saw and emphasized with great rigour was the impossibility of bridging the gap opened up by the Cartesian split between mind and matter. Berkeley's target is the comfortable, commonsense view of mind as entirely different from matter, yet in satisfactory contact with a material world about which it can know a great deal. He deploys many of the arguments of ancient scepticism, and others found in Malebranche and Bayle, to undermine this synthesis, showing that once the separation of mind from the material world is as complete as Descartes makes it, the hope of knowing or understanding anything about the supposed external world quite vanishes. A relationship of resemblance, for example, whereby our ideas can be taken to resemble qualities in things that give rise to them, is unknowable and unintelligible. Unlike Cartesian scepticism, which stresses the bare possibility of things not being as we take them to be, Berkeley urges the actual inconsistencies within the conceptual scheme left by Cartesianism, that entrap such thinkers as Locke (and, arguably, common sense itself). His way out is not to advocate scepticism, which he consistently regards with extreme repugnance, but to reformat the relation between mind and the world so that contact is re-established. Unfortunately this introduces subjective idealism, in which what the subject apprehends as the world is just the relationship between the subject's own mental states (plus an uneasy relationship with archetypes of the subject's ideas in the mind of God). In promoting his system Berkeley makes brilliant use of the sceptical problems that will bedevil alternatives, as well as of the problems faced by particular elements of the conceptual scheme he opposes: problems of causation, substance, perception and understanding. Although his system has proved incredible to virtually all subsequent philosophers, its importance lies in the challenge it offers to a common sense that vaguely hopes that these notions fit together in a satisfactory way.