Stephan Körner, FBA (26 September 1913 – 17 August 2000) was a British philosopher, who specialised in the work of Kant, the study of concepts, and in the philosophy of mathematics. Born to a Jewish family in Czechoslovakia, he left the country to avoid certain death at the hands of the Nazis after the German occupation in 1939, and came to the United Kingdom as a refugee, where he began his study of philosophy; by 1952 he was a professor of philosophy at the University of Bristol, taking up a second professorship at Yale in 1970. He was married to Edith Körner, and was the father of the mathematician Thomas Körner and the biochemist, writer and translator (née) Ann M. Körner.
Körner was born in Ostrava, then part of Austria-Hungary, in 1913, the son of a teacher of classics and his wife. His father had studied classics in Vienna, while at the same time, winning prizes in mathematics to supplement his meager income (a fellow student was a certain Leo Trotsky, who was frequently asked, "When is that great revolution that you are always talking about going to happen?"). Despite an early wish to study philosophy, Stephan was dissuaded by his father, who feared that his son would become a penniless academic; he was persuaded to study something more practical, and took his degree in law at Charles University in Prague, completing it in 1935. (He practised law only briefly but retained a strong interest, attending seminars at Yale Law School after his appointment as a visiting professor at Yale in the 1970s.) From 1936 to 1939 he carried out his military service, serving as an officer in the cavalry (see photograph).