The Lwów–Warsaw school (Polish: Szkoła lwowsko-warszawska) was a Polish school of thought founded by Kazimierz Twardowski in 1895 in Lwów. Although the members represented a variety of disciplines, from mathematics through logic to psychology, the School is widely considered to have been a philosophical movement. Developed in the 1920s and 1930s, the school's work was interrupted by the outbreak of World War II. Despite this, the members went on and fundamentally influenced modern science, notably mathematics and logic, in the post-war period. Perhaps the most prominent member of this school, Alfred Tarski, has been ranked as one of the four greatest logicians of all time — along with Aristotle, Gottlob Frege, and Kurt Gödel.