Philosopher, born in Königsberg, Germany. He spent his entire life there, studying at the university, and becoming professor of logic and metaphysics in 1770. His main work, now a philsophical classic, is the Kritik der reinen Vernunft (1781, Critique of Pure Reason), in which he provided a response to the empiricism of Hume. His views on ethics are set out in the Grundlagen zur Metaphysik der Sitten (1788, Critique of Practical Reason), in which he elaborates on the Categorical Imperative as the supreme principle of morality. In his third and last Critique, the Kritik der Urteilskraft (1790, Critique of Judgement), he argued that aesthetic judgements, although universal, do not depend on any property (such as beauty or sublimity) of the object. His thought exerted great influence on subsequent philsophy.