John Locke

John Locke was an English philosopher and physician, often regarded as the founder of British empiricism and one of the main sources of liberal political thought. In An Essay Concerning Human Understanding he argued that all our ideas come from experience, and in the Two Treatises of Government he defended natural rights, government by consent and the right to resist tyranny. His ideas on toleration, property and the limits of power were taken up by the Enlightenment and the American revolutionaries.

Locke was born on 29 August 1632 at Wrington in Somerset, in the Kingdom of England, to a Puritan family. His father was a country lawyer who served as a captain in the Parliamentary cavalry during the first years of the English Civil War. Through his father's commander, Locke gained a place at Westminster School in London, and in 1652 he went on to Christ Church, Oxford.

Like many of his contemporaries he found the Oxford curriculum, still based on Aristotle and scholastic disputation, dry and unprofitable. He was more excited by the new philosophy of René Descartes and by experimental science. He became a lecturer at Christ Church, studied medicine and worked with the chemist Robert Boyle and the physician Thomas Sydenham, who taught him the value of careful observation of disease.

In 1666 Locke met Anthony Ashley Cooper, later the first Earl of Shaftesbury, one of the most powerful politicians of Restoration England. He moved into his household in London as physician and adviser, and in 1668 supervised an operation on a liver abscess that was credited with saving Shaftesbury's life. That year he was elected a Fellow of the Royal Society.

Through Shaftesbury Locke became involved in government and colonial affairs. He served as secretary to the Lords Proprietors of Carolina and helped draft its Fundamental Constitutions (1669), which gave colonists absolute power over enslaved Africans, and he invested in the Royal African Company, which traded in slaves. His involvement in slavery sits uneasily with his theory of natural freedom and is much discussed by historians. From 1675 to 1679 he lived in France, where he met leading scholars and kept detailed journals.

Back in England, Shaftesbury led the campaign to exclude the Catholic Duke of York, the future James II, from the succession. When this failed he fled to the Netherlands, where he died in 1683. After the discovery of the Rye House Plot to kill Charles II and his brother that year, Locke, who was under government watch, also left for the Dutch Republic. He lived there, partly in Amsterdam, for more than five years, at times under a false name, and was expelled from his studentship at Christ Church on royal orders.

The Glorious Revolution of 1688 replaced James II with William of Orange and Mary. Locke crossed back to England in February 1689 on the same ship as the new queen. Within the next year, three of his major works appeared. He served as a commissioner on the Board of Trade from 1696 to 1700, advised on the reform of the coinage, and spent his last years at Oates, the Essex manor of Sir Francis Masham and his wife Damaris, a philosopher and old friend. He died there on 28 October 1704 and is buried at High Laver nearby.

An Essay Concerning Human Understanding was published in December 1689, though dated 1690. Locke set out to find the origin, extent and limits of human knowledge. He rejected the doctrine of innate ideas, arguing that the mind at birth is like a blank sheet of paper, often called a tabula rasa, and that all our ideas come from experience, either from sensation of the outside world or from reflection on the workings of our own minds. Complex ideas are built from simple ones.

He distinguished primary qualities, such as size, shape and motion, which really exist in objects, from secondary qualities, such as colour, taste and sound, which are powers in objects to produce sensations in us. He offered an influential account of personal identity, holding that what makes someone the same person over time is continuity of consciousness and memory rather than the same body or soul. He stressed that much of what we believe is probable rather than certain, and that the strength of belief should match the evidence. These ideas were developed and challenged by George Berkeley, David Hume and Gottfried Wilhelm Leibniz.

The Two Treatises of Government were published anonymously in 1689, also dated 1690, though much of the text was written years earlier, during the crisis over the succession. The first treatise attacks Sir Robert Filmer's theory that kings inherit absolute power from Adam. The second sets out Locke's own theory. In the state of nature, people are free and equal and bound by a natural law that forbids harming others in their life, health, liberty or possessions. People gain property by mixing their labour with what nature provides. They form civil society by consent to protect these rights more securely. Government is a trust, and when rulers violate it by seizing people's property or acting outside the law, the people may resist and set up a new government.

Unlike Thomas Hobbes, who had used a similar starting point to defend an unlimited sovereign, Locke argued for limited government with a separate legislature and executive. In A Letter Concerning Toleration (1689) he argued that the state's task is to protect civil interests, not to save souls, and that belief cannot be forced, so religious persecution is both wrong and useless. He did not extend this toleration to atheists or to Catholics, whom he regarded as loyal to a foreign power. His other works include Some Thoughts Concerning Education (1693) and The Reasonableness of Christianity (1695).

Locke's Essay became one of the most widely read philosophical books of the eighteenth century, and Voltaire did much to popularise him in France, making him a hero of the Age of Enlightenment. His political theory was used to justify the revolution of 1688, although historians note it was cited less at the time than later. Its language of natural rights and government by consent echoes in the American Declaration of Independence drafted by Thomas Jefferson and in the American Revolution more widely. He stands at the turn from early modern philosophy to the Enlightenment, and is a key figure in the history of the United Kingdom.