George BERKELEY (1685-1753), philosopher, was born at Dysart Castle in Co. Kilkenny, and educated at Kilkenny College and Trinity College, Dublin. He travelled abroad and in 1728 went to America in connection with an abortive scheme for a missionary college in Bermuda. He was appointed dean of Derry in 1724 and bishop of Cloyne in 1734. His chief philosophical works were "An Essay towards a New Theory of Vision" (1732), "A Treatise concerning the Principles of Human Knowledge" (1734) and "Three Dialogues between Hylas and Philonous" (1734). In 1712 hi published controversial sermons on "passive obedience" and a year later contributed essays against the Whig free-thinkers. His three-volume compilation "The Ladies Library" appeared in 1714. In his works of vision, Berkeley seeks to show the mind-dependence of the ideas derived from sight, and explains their arbitrary though constant connection with the more primary ideas of touch by analogy with the way in which written words signify speech. Berkeley was a master both of English prose and of the dialogue form; he is remarkable for his lucidity, grace, and dignity of expression.