Immanuel Kant

Immanuel Kant was born in Königsberg, in East Prussia, on 22 April 1724, the son of a harness-maker. Brought up in a devout Pietist household, he studied at the Collegium Fridericianum and from 1740 at the University of Königsberg, where he was drawn above all to mathematics and Newtonian physics. After his father's death he spent several years as a private tutor in country houses, then returned to the university in 1755 as a lecturer. In the same year he published his Universal Natural History and Theory of the Heavens, which explained the origin of the solar system from a rotating cloud of matter.

For fifteen years he lectured on an astonishing range of subjects — logic, metaphysics, ethics, physics, mathematics, geography and anthropology — and became known as a brilliant and witty teacher. In 1770 he was appointed professor of logic and metaphysics. There followed a "silent decade" in which he published almost nothing while working out a new foundation for philosophy. In 1781 it appeared: the Critique of Pure Reason, which asked what reason can know without experience and answered that the mind itself gives form to the world it knows.

The great works then came in quick succession: the Prolegomena (1783), the Groundwork of the Metaphysics of Morals (1785), with its categorical imperative, the Critique of Practical Reason (1788) and the Critique of the Power of Judgement (1790). Alongside them he wrote short essays for a wider public, among them An Answer to the Question: What Is Enlightenment? and Idea for a Universal History with a Cosmopolitan Aim (both 1784), and later Toward Perpetual Peace (1795). His Religion within the Bounds of Mere Reason (1793) brought a royal reprimand under Frederick William II, and Kant promised to write no more on religion during the king's lifetime.

Kant never travelled far from Königsberg, and the regularity of his days became legendary. He lectured until 1796 and died in his native city on 12 February 1804. His last words are said to have been "Es ist gut" — "It is good." He is buried beside the cathedral of Königsberg.

Few philosophers have changed the course of thought so profoundly. Kant's critical philosophy stands at the source of German idealism and of most later theories of knowledge; his ethics of autonomy and human dignity remains a foundation of moral and legal thought; and his writings on enlightenment, cosmopolitan right and perpetual peace still shape debates on freedom of thought, human rights and international order.