Born Aug. 29, 1632, in Wrington; died Oct. 28, 1704, in Oates. English Enlightenment philosopher and political thinker who developed an empirical theory of cognition and the political philosophy of liberalism.

Locke’s father was a Puritan and a small landowner. Locke graduated from Westminster School and Oxford University, where he subsequently taught. He studied experimental chemistry, meteorology, and medicine, and in 1668 he was elected to the London Royal Society. In 1667 he became the private physician and later the personal secretary of Lord Ashley, Earl of Shaftesbury, a prominent public figure during the Restoration. His association with Shaftesbury led him into politics. Like Shaftesbury, he escaped the persecution of the English government by emigrating in 1683 to Holland, where he joined the supporters of William of Orange. Locke returned to his native land in 1689, after William of Orange had become king of England, and from 1691 he lived at the Masham estate in Oates, devoting himself chiefly to scholarship.

Locke’s philosophy rests on his theory of knowledge, which he constructed in the tradition of F. Bacon’s empiricism and materialism, in opposition to Cartesianism, the Cambridge Platonists, and the scholastic philosophy prevailing in the universities. Locke was also influenced by P. Gassendi, R. Boyle, T. Sydenham, and I. Newton. His principal work, An Essay Concerning Human Understanding (1690), on which he worked for almost 20 years, examines the origin, types, and potentials of human cognition.

According to Locke, innate ideas and principles—whether theoretical or practical (moral), including the idea of god—do not exist; all human knowledge proceeds from experience. All ideas originate in two fundamental sources: external experience (sensation) and internal experience (reflection). Knowledge is based on simple ideas, for example, those which are stimulated in the mind by various qualities of bodies, either primary characteristics, which these ideas resemble (length, shape, density, movement), or secondary qualities (color, sound, smell, or taste), which these ideas do not resemble. Reason forms complex, general ideas (modes, substances, relations) from simple ones by combination, contrast, and abstraction. Locke distinguishes between clear and obscure ideas, real and “fantastical” ideas, and ideas that are adequate or inadequate to their archetypes. He believes that cognition is real only insofar as its ideas conform to reality. He defines truth as the joining or separating of ideas or their signs according to the correspondence or lack of correspondence between the ideas and the objects designated by them. With respect to the meaning of general terms, Locke tends toward conceptualism, noting that the real essence of objects remains unknown and that the mind deals with nominal substances. Locke divides cognition into intuition (self-evident truths, our own existence), demonstration (mathematical and ethical propositions, the existence of god), and sensitive knowledge (the existence of individual objects). He regards sensitive knowledge as the least clear and certain, thus introducing an obviously rationalist element into his conception.

Related to Locke’s Essay Concerning Human Understanding are his works On the Use of Reason (published in 1706) and Examination of the Opinion of Father Malebranche on Seeing All Things in God (1694), as well as his replies to the theologians Norris and Stillingfleet. Of special interest in Locke’s correspondence with Stillingfleet (1697–98) are his ideas about the ability of material substance to think and the criteria for authentic knowledge.

Opposing the fanaticism of different religious groups, Locke persistently advocated toleration. In defense of religious freedom he wrote four letters on toleration (published 1689, 1690, 1692, and 1706). In The Reasonableness of Christianity (1695), Locke attempted to separate, from a Protestant standpoint, the “true” teachings of Christ from subsequent alterations. Locke’s views were close to deism and unitarianism. He believed, however, that since human reason is limited, Christianity, even rational Christianity, requires revelation and the experience of god “through his spirit,” without which any religion is meaningless.

Although Locke held that ethics could become a science similar to mathematics and precisely analyzed ethical terms and statements, he did not create a consistent ethical theory. By defining moral good as the subjection of man’s volitional acts to law rooted in the divine will (the “true basis of morality”), Locke modified his utilitarian maxims that the good is that which causes or increases pleasure and reduces suffering and that happiness (the striving for which is the basis of all freedom) results from the attainment of the good. Harmony between personal and public interests is ultimately achieved in wise and devout consciousness.

In Some Thoughts Concerning Education (1693), Locke proceeds from the idea of the decisive influence of environment on education and of the importance of considering the child’s natural aptitudes and developing a sound mind and body. The work became a classic treatise on pedagogy. Initially, the child is completely under the influence of parents and educators, who should set an example; as the child matures, he gains his freedom. Attributing to maturity “the use of reason” and thus fruitful instruction, Locke believes that education should begin only after the child’s character has been formed (in the family and not in school) and principles of morality inculcated. Locke opposes the goals, content, and methods of scholastic instruction, advocating a curriculum that would meet the practical needs of bourgeois society. Education should be based on developing the child’s interest in learning and curiosity. He reduces to a minimum the teaching of ancient languages and stresses the importance of studying the native tongue. Besides modern languages and mathematics (which particularly aids the development of thinking), he introduces into the curriculum the study of history, geography, principles of law, and “natural philosophy.”

Locke’s sociopolitical concepts are contained in Two Treatises of Government (1690). The first treatise attempts to refute R. Filmer’s views on the divine right of absolute monarchy, and the second expounds a theory of constitutional parliamentary monarchy that essentially justifies the sociopolitical structure established in England after the Revolution of 1688–89. Locke shows the inevitability of state authority from the standpoint of the theory of natural law and the social contract. In contrast to T. Hobbes’ absolutist theory of the state, Locke believes that government is entrusted with only certain “natural rights” (the rendering of justice, foreign relations) so that all the other rights—freedom of speech, religion, and, above all, property—might be effectively protected. In order to prevent abuses, the state’s legislative authority must be separated from its executive (including judicial) and “federative” (foreign relations) powers; moreover, the government itself must obey the law. The people remain the unquestioned sovereign and have the right to refuse to support and even to overthrow an irresponsible government. In his economic theories, he adheres to mercantilism and the labor theory of value.

Locke’s ideas were extremely important for the philosophical and sociopolitical thought of the European Enlightenment, significantly influencing the English deists J. Toland and J. Priestley, Voltaire and Condillac in France, and, particularly, the French 18th century materialists La Mettrie, C. Helvétius, and D. Diderot. The English idealist G. Berkeley and the agnostic D. Hume were also indebted to him. Locke’s ideas laid the foundation for the development of associationism in psychology. Progressive pedagogy in the 18th century and Utopian socialism in the early 19th century were based on Locke’s theory of education. According to Marx, Locke’s political philosophy was “the classical expression of bourgeois society’s ideas of right as against feudal society” (K. Marx, and F. Engels, Soch., 2nd ed., vol. 26, part 1, p. 371). It was developed by Montesquieu and was reflected in the political theories of the French and American bourgeois revolutions.