 The interwar period was most fruitful for Łukasiewicz. He was a leading figure, with Leśniewski and Tarski, in what became known as the Warsaw School of Logic. He made a friend of the only German professor of mathematical logic, Heinrich Scholz, and was awarded an honorary doctorate by the latter’s University of Münster in 1938. Other honors awarded him in this period were Grand Commander of the Order of Polonia Restituta (1923), Grand Commander of the Hungarian Order of Merit, a monetary award from the City of Warsaw (1935) and memberships of the Polish Academy of Arts and Sciences in Kraków, and the Polish Scientific Societies in Lwów and Warsaw.