Lvov-Warsaw School First published Thu May 29, 2003; substantive revision Wed Aug 28, 2013 The Lvov-Warsaw School (LWS) was the most important movement in the history of Polish philosophy. It was established by Kazimierz Twardowski at the end of the 19th century in Lvov, a city at that time belonged to the Austro-Hungarian Empire. The LWS flourished in the years 1918–1939. Kazimierz Ajdukiewicz, Tadeusz Kotarbiński, Stanisław Leśniewski, Jan Łukasiewicz and Alfred Tarski are its most famous members. It was an analytical school similar to the Vienna Circle in many respects. On the other hand, the attitude of the LWS toward traditional philosophy was much more positive than that of logical empiricism. Although logic became the most important field in the activities of the LWS, its members were active in all spheres of philosophy. World War II and political changes in Poland after 1945 caused the end of the LWS as an organized philosophical enterprise. One can consider it to have later been continued individually by its representatives. 1. The Origin and Development of the Lvov-Warsaw School Kazimierz Twardowski (1866–1938) began his post as professor of philosophy at Lvov University in 1895. He came to Lvov from Vienna, where he had studied philosophy under Franz Brentano and Robert Zimmermann. Twardowski belonged to the last group of Brentano's students. His Habilitationschrift (1894) concerned the concepts of the content and the object of presentations; it clarified and sharpened this important distinction. This work strongly influenced Meinong and Husserl. Twardowski appeared in Lvov with the ambitious plan of creating a scientific philosophy (in Brentano's spirit) in Poland (at that time, Poland was partitioned between Austro-Hungary, Germany and Russia; Lvov belonged to the Austro-Hungarian Empire.) In fact, he subordinated all his activities to achieving this task and considerably limited his own scientific work. Twardowski was an extraordinary and charismatic teacher. He very soon attracted many young people to philosophy. After ten years of teaching he sometimes had about 200 candidates for seminars and 2000 attendants of his lectures. He propagated a clear style of writing and speaking about philosophical matters, insisted upon justification of philosophical theses and sharply distinguished philosophy as a science from world-views. Following Brentano, he favoured problems on the borderline of descriptive psychology, grammar and logic (he supplemented his object/content distinction by that of actions/products). A photo of Twardowski's last seminar participants taken during the 1936–1937 academic year is available (see the supplement [1]), with most of the participants identified. Although Twardowski was not a logician and did not consider himself as such, his program formed a friendly environment for logic in all its subdomains: formal logic, semantics and methodology of science. Jan Łukasiewicz (1878–1956) was the first of Twardowski's students to be interested in logic. He began his lectures in logic in Lvov in 1906. Kazimierz Ajdukiewicz (1890–1963), Tadeusz Czeżowski (1889–1981), Tadeusz Kotarbiński (1886–1981) and Zygmunt Zawirski (1882–1948) studied mainly under Twardowski, but they also attended courses conducted by Łukasiewicz. Stanisław Leśniewski (1886–1939) joined this circle in 1910. Warsaw appeared on the stage exactly in 1915, when the University of Warsaw was reopened. The academic staff was mainly imported from Lvov; Łukasiewicz was appointed professor of philosophy. Poland recovered its independence in 1918 and Polish scholars began to build national academic life. The program for the development of mathematics elaborated by a mathematician Zygmunt Janiszewski (the Janiszewski program) had a great importance for the subsequent development of the LWS. According the Janiszewski program, Polish mathematicians should concentrate on set theory, topology and their applications to other branches of mathematics. In particular, the Janiszewski program attached great importance to mathematical logic and the foundations of mathematics. Two philosophers, namely Leśniewski and Łukasiewicz, became professors of the University of Warsaw at the Faculty of Mathematical and Natural Sciences. Both began intensive teaching of mathematical logic, mostly among mathematicians but also among philosophers. Thus, logic in the LWS had two parents: mathematics and philosophy. Alfred Tarski (1901–1983) opened the list of young mathematicians and philosophers attracted by logic in Warsaw. The logical community in this city included (in alphabetical order and covering the whole period 1918–1939: Stanisław Jaśkowski (1906–1965), Adolf Lindenbaum (1904– 1941?), Andrzej Mostowski (1913–1975), Moses Presburger (1904?-1943), Jerzy Słupecki (1904-1987), Bolesław Sobociński (1904–1980; a philosopher by training)) and Mordechaj Wajsberg (1902–1942?). The names of three other logicians who graduated shortly before 1939 or studied during War World II and began their academic work after 1945 should be added, namely Jan Kalicki (1922–1953; a mathematician), Czesław Lejewski (1913–2001; a classicist and philosopher) and Henryk Hiż (1917; a philosopher). The development of logic in Warsaw had two subperiods in 1918–1939, namely 1918–1929 and 1929–1939. The first decade consisted in intensive teaching and scientific work at the seminars of Leśniewski and Łukasiewicz. Not many results were published at that time. The explosion of publications took place in 1929 and later. There are several factors which caused the development of mathematical logic in Poland. The Warsaw school of logic appears to be model case, but the power of this circle influenced other places where the general environment was not so favourable to logic. The fruitful co-operation of mathematicians and philosophers in Warszawa had the utmost significance. The founders of the Polish mathematical school made a brave experiment consisting in inviting two philosophers with a modest mathematical background as professors at the Faculty of Mathematics and Natural Sciences; this did not happen in any other country. The gifts of Leśniewski and Łukasiewicz as teachers and the abilities of the latter as an organizer attracted young mathematicians. In Poland mathematical logic was considered to be an autonomous science, not a part of mathematics or philosophy. From the present-day point of view this might seem as an exaggeration, but this ideology contributed essentially to the strength of Polish logic. Their representatives were fairly conscious of the fact that the propagation and defence of the autonomy of this field had to be confirmed by important scientific results and international recognition. Moreover, this view about logic motivated various purely theoretical investigations on formal systems. On the other hand, Polish logicians strongly insisted that logic should not be restricted only to mathematics and required the co-operation of representatives of all field in which logic might be used. Still another factor played an important role, namely the conviction about the social significance of logic as a weapon against all kinds of irrationalism. Tarski once said “Religion [you can also say “ideology” — JW] divides people, logic brings them together.” According to Łukasiewicz, “Logic is morality of thought and speech”. Thus, Polish logicians doing logic and teaching it were convinced that they were performing an important social service. Kotarbiński was appointed professor of philosophy in Warsaw in 1919. His teaching activity resulted in a group of scholars working mainly in the philosophy of science, including Janina Hosiasson (later Mrs. Lindenbaum; 1899–1942), Edward Poznański (1901–1976), Dina Sztejnbarg (later Mrs. Kotarbiński) (1901–1997) and Aleksander Wundheiler (1902– 1957). Twardowski and Ajdukiewicz (appointed professor in 1928) remained in Lvov. They trained a group that included Izydora Dąmbska (1904–1983), Maria Kokoszyńska (1905–1981), Henryk Mehlberg (1904–1978) and Zygmunt Schmierer (?–1943). Although Twardowski's students also taught at other Polish universities (Czeżowski in Vilna, Zawirski in Poznań and Kraków), Lvov and Warsawa were the main centres of the LWS. The school was also joined by a group of catholic philosophers, including Father Innocenty (Józef) M. Bocheński (1902–1995) and Father Jan Salamucha (1904–1944). World War II had disastrous consequences for the LWS. Twardowski and Leśniewski died before September 1, 1939. Of the people mentioned above who lost their lives (mostly Jews murdered by the Nazis): the Lindenbaums, Presburger, Salamucha, Schmierer and Wajsberg. Zawirski died in 1947. Many emigrated from Poland during World War II or shortly after it: Łukasiewicz (Dublin), Tarski (Berkeley), Hiż (Philadelphia), Kalicki (Berkeley), Lejewski (Manchester), Mehlberg (Toronto, Chicago), Sobociński (Notre Dame) and Wundheiler (New York); Bocheński (Fribourge) and Poznański (Jerusalem, before 1939). The situation in Poland in 1945–1948 was similar as before 1939. The Marxist ideological offensive against bourgeois philosophy started in 1949. The policy became more liberal after 1956. Although many scholars of the LWS actively taught and worked in the new political reality, it would be difficult to say that the school continued its former manner of existence. The tradition of the LWS was rather preserved in individual hands, but not as an organized enterprise. Note: the present essay focuses on the logical wing of the LWS. In 1939, the entire school