1820 in philosophy

Publications

 * Thomas Brown - Lectures on the Philosophy of the Human Mind
 * Georg Wilhelm Friedrich Hegel - Grundlinien der Philosophie des Rechts

Births

 * 22 January - James Hutchison Stirling, English philosopher (died 1909)
 * 27 April – Herbert Spencer, English philosopher and sociologist (died 1903)
 * 23 June – Friedrich Hermann Semmig, German author and philosopher (died 1897)
 * 28 November – Friedrich Engels, German revolutionary, political economist, philosopher, industrialist, and military historian (died 1895)

Deaths

 * 24 March – Jean-Baptiste-René Robinet, French philosopher (born 1735)
 * 2 April – Thomas Brown, Scottish philosopher and doctor (born 1778)
 * 20 July – Mattias Fremling, Swedish philosopher (born 1745)