Kazimierz Twardowski

Kazimierz Twardowski (1866-1938) was a Polish philosopher, psychologist and logician who shaped the intellectual life of his country in the first half of the twentieth century. Trained in the Austrian philosophical tradition, he is known as the father of Polish logic and as the founder of a style of philosophy built on clear, rigorous analysis.

He studied in Vienna under Franz Brentano and Robert von Zimmermann. He earned his doctorate with a dissertation on ideas and perception in Descartes and, in 1894, published his work on the content and object of presentations, which remains his best-known book. After lecturing in Vienna, he was appointed professor at Lwów, then Lemberg in Austrian Galicia and now Lviv in Ukraine, where he spent most of his career. He later served as rector of the university during the First World War. There he founded the Lwów-Warsaw school, whose members included Leśniewski, Łukasiewicz and Ajdukiewicz, and which gave Poland a tradition of scientific philosophy.

His thinking starts from Brentano's idea of intentionality: every mental act is directed at something. Twardowski noticed that the word presentation was sometimes used for the object in the world and sometimes for the inner content of the mind. To resolve this ambiguity, he distinguished content from object. Just as a painted picture depicts a painted landscape, a presentation has a mental content and an object to which it refers.

Twardowski also championed experimental psychology, opening the first laboratory of its kind in Poland in 1907. He founded the Polish Philosophical Society in 1904 and the journal Ruch Filozoficzny in 1911. He officially retired in 1930. His influence reached formal logic and analytic philosophy through his students, several of whom were close to the Vienna Circle.