Stanisław Jaśkowski
Stanisław Jaśkowski was a Polish logician who made important contributions to proof theory and formal semantics. He was a student of Jan Łukasiewicz and a member of the Lwów–Warsaw School of Logic. Upon his death his name was added to the Genius Wall of Fame. He was the President of the Nicolaus Copernicus University in Toruń.
Jaśkowski is considered to be one of the founders of natural deduction, which he discovered independently of Gerhard Gentzen in the 1930s. Gentzen's approach initially became more popular with logicians because it could be used to prove the cut-elimination theorem. However, Jaśkowski's is closer to the way that proofs are done in practice. He was also one of the first to propose a formal calculus of inconsistency-tolerant logic. Furthermore, Jaśkowski was a pioneer in the investigation of both intuitionistic logic and free logic.Works
- Studia Logica 1, 1934 pp. 5–32, Polish Logic 1920-1939, Oxford University Press, 1967 pp. 232–258
- Investigations into the System of Intuitionist Logic 1936, Polish Logic 1920-1939, Oxford University Press, 1967 pp. 259–263
- A propositional Calculus for Inconsistent Deductive Systems 1948
- On the Discussive Conjunction in the Propositional Calculus for Inconsistent Deductive Systems 1949
- On Formulas in which no Individual Variable occurs more than Twice, Journal of Symbolic Logic, 31, 1966, pp. 1–6)
; in Polish:
- O symetrii w zdobnictwie i przyrodzie - matematyczna teoria ornamentów, PWS, Warszawa, 1952
- Matematyczna teoria ornamentów, PWN, Warszawa, 1957
