Locke, John (1632-1704), one of the greatest English metaphysicians, and the establisher of the empirical system of moral philosophy, was born at Wrington, in Somersetshire, and educated at Westminster and Christ Church, Oxford. In 1658 he took up the study of physic, and in 1666 became physician to Lord Ashley (the first Earl of Shaftesbury), in whose house he took up his residence, and who enabled and induced him to devote himself to politics and philosophy. Eventually his patron made him secretary to the Board of Trade, but he lost the appointment in 1674, and resided in France for his health from 1675 to 1679. In 1682 he accompanied the exiled Shaftesbury to Holland, and, falling under the suspicion of disloyalty, was deprived of his studentship in Christ Church by King Charles. After Monmouth's rising his person was demanded by King James's envoy at the Hague, so that he had to spend a year in hiding (1685-86), when he wrote his first Letter concerning Toleration. At the Revolution he returned to England, and was made a Commissioner of Appeals. His celebrated Essay concerning Human Understanding, which had been in preparation for nearly twenty years, was published in 1690, when he also produced his second Letter on Toleration and his two Treatises on Government (one attacking Filmer (q.v.), the other adapting the Social Contract theory to justify the English revolution), in opposition to the doctrines of passive obedience. In the next year he wrote on finance; in 1692 he issued his third Letter on Toleration; in 1693 his Thoughts concerning Education. He was made a Commissioner of Trade and Plantations in 1695, which post he held until failing health, caused by asthma, induced him to retire. His latest works were the Reasonableness of Christianity, Two Vindications against the attacks of Dr. Edwards, who had charged him with Socinianism, and his controversial writings in answer to Dr. Stillingfleet's animadversions on the Essay concerning Human Understanding. In his great work he studied the origin of ideas and mental operations and affections by careful analysis of his own consciousness, with the result that he derived all knowledge from experience. Considering that a loose and inaccurate use of words was one of the main sources of error, Locke aimed with considerable success at being simple and clear in his style, and at investing with distinctness the notions with which he dealt; so that (in spite of a tendency to diffuseness) he exercised a great and beneficial influence on literary style, as well as on mental and moral philosophy. The declining portion of his life was solaced by the friendship of Lady Masham, the daughter of his intimate friend, Dr. Cudworth (q.v.).