Immanuel Kant

Immanuel Kant was a Prussian philosopher of the Enlightenment who spent nearly his entire life in Königsberg. After years as a private tutor and then as a lecturer, he became professor of logic and metaphysics at the city's university. His "critical philosophy" examined the limits and conditions of human knowledge, most famously in the Critique of Pure Reason (1781). In ethics he formulated the "categorical imperative," a proposed universal test for moral action. His writings on knowledge, ethics, aesthetics, and politics, including the essay Perpetual Peace, became central reference points for later European thought. He died in Königsberg in 1804.