December 21

Jan Łukasiewicz was born in 1878 and became a pioneering figure in modern logic and philosophy. He introduced Polish notation, a parenthesis-free system for writing logical expressions that streamlined formal proofs. Łukasiewicz also developed multi-valued logics, extending classical true-false logic to include additional truth values. His work on the logic of Aristotle and on the foundations of mathematics influenced thinkers across Europe. In 1940, he accepted an academic position at University College Dublin, where he continued his research and teaching. Łukasiewicz published numerous papers and books that remain central to studies of logic and the history of philosophy. He held that logic and clarity of thought were essential for philosophical inquiry until his death in 1956.