# Mathematician:Jan Łukasiewicz

## Contents

## Mathematician

Polish philosopher who contributed significantly to logic.

Most famous for his innovation Polish notation, a technique which allows one to write expressions without the need for parentheses.

## Nationality

Polish

## History

- Born: 21 Dec 1878, Lwów, Austrian Galicia, known as Lemberg in German (now L'viv, Ukraine)
- 1890–1902: studies with Kazimierz Twardowski in Lemberg
- 1902: Doctorate (mathematics and philosophy), University of Lemberg with the highest distinction possible
- 1906: Habilitation thesis completed, University of Lemberg
- 1906: Becomes a lecturer
- 1910: Essays on the Principle of Non-Contradiction and the Law of Excluded Middle
- 1911: Extraordinary professor at Lemberg
- 1915: Invited to the newly reopened University of Warsaw
- 1916: New Kingdom of Poland declared
- 1917: Develops three-valued logic
- 1919: Polish Minister of Education
- 1920: Professor at Warsaw University
- 1920–1939: Founds with Stanisław Leśniewski the Lwów–Warsaw school of logic (see also Alfred Tarski, Stefan Banach, Hugo Steinhaus, Zygmunt Janiszewski, Stefan Mazurkiewicz)
- 1928: Marries Regina Barwińska
- 1944: Flees to Germany and settles in Hembsen, where he was brought for his own safety.
- 1946: Exile in Belgium
- 1946: Offered a chair by the Royal Irish Academy, held at University College Dublin
- 1953: Writes autobiography
- Died: 13 Feb 1956, Dublin, Ireland

## Theorems and Definitions

## Publications

- 1903:
*On Induction as Inversion of Deduction* - 1906:
*Analysis and Construction of the Concept of Cause* - 1910:
*On Aristotle's Principle of Contradiction* - 1913:
*On the Reversibility of the Relation of Ground and Consequence* - 1920:
*On Three-valued Logic* - 1921:
*Two-valued Logic* - 1922:
*A Numerical Interpretation of the Theory of Propositions* - 1928:
*Concerning the Method in Philosophy* - 1929:
*Elementy Logiki Matematycznej*(*Elements of Mathematical Logic*) - 1929:
*On Importance and Requirements of Mathematical Logic* - 1930:
*Philosophical Remarks on Many-Valued Systems of Propositional Logic* - 1930:
*Untersuchungen über den Aussagenkalkül*("Investigations into the Sentential Calculus") (*Comptes Rendus des Séances de la Société des Sciences et des Lettres de Varsovie, Classe III***Vol. 23**: 30 – 50) (with Alfred Tarski) - 1931:
*Comments on Nicod's Axiom and the 'Generalizing Deduction'* - 1934:
*On Science* - 1934:
*Importance of Logical Analysis for Knowledge* - 1934:
*Outlines of the History of the Propositional Logic* - 1936:
*Logistic and Philosophy* - 1937:
*In Defense of the Logistic* - 1938:
*On Descartes's Philosophy* - 1943:
*The Shortest Axiom of the Implicational Calculus of Propositions* - 1951:
*On Variable Functors of Propositional Arguments* - 1951:
*Aristotle's Syllogistic from the Standpoint of Modern Formal Logic* - 1952:
*On the Intuitionistic Theory of Deduction* - 1957:
*Aristotle's Syllogistic from the Standpoint of Modern Formal Logic*(2nd Edition, enlarged) - 1958:
*Elementy logiki matematycznej*(translated as*Elements of Mathematical Logic*by Olgierd Wojtasiewicz in 1964)

## Sources

- John J. O'Connor and Edmund F. Robertson: "Jan Łukasiewicz": MacTutor History of Mathematics archive

- 1946: Alfred Tarski:
*Introduction to Logic and to the Methodology of Deductive Sciences*(2nd ed.) ... (previous) ... (next): $\S \text{II}.7$: Sentential Calculus (footnote)