Jan ?ukasiewicz

Jan ?ukasiewicz (born 21 December, 1878 - 31 February, 1977) was a Polish mathematician born in Lw?w, Galicia (now L'viv, Ukraine). His major mathematical work centred on mathematical logic. He thought innovatively about traditional propositional logic, the principle of non-contradiction and the law of excluded middle.

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?ukasiewicz worked on multi-valued logics, including his own three-valued propositional calculus, the first non-classical logical calculus. He is responsible for one of the most elegant axiomatizations of classical propositional logic; it has just three axioms and is one of the most used axiomatizations today. He also pursued philosophy, approaching the human aspects of scientific theory-making with ideas similar to those of Karl Popper.

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?ukasiewicz's Polish notation of 1920 was at the root of the idea of the recursive stack a last-in, first-out computer memory store invented by Charles Hamblin of the New South Wales University of Technology (NSWUT), and first implemented in 1957. This design led to the English Electric multi-programmed KDF9 computer system of 1963, which had two such hardware register stacks. A similar concept underlies the reverse Polish notation (or postfix notation) of Hewlett Packard calculators, or the PostScript page description language.

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21 December: REDIRECT December 21...

1878: 1878 was a common year starting on Tuesday (see link for calendar)....

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Jan ?ukasiewicz related Images and Photos (experimental)

Jan Sterling	Jan-Michael Vincent	"Skiing Woman " Jan/Feb 84	1984 Jan Sterling Edmond O'Brien 1956
Jan Van Riebeeck Lands in Table Bay Where He Founds Cape Town	The Martyrdom of Jan Hus	The Brady Bunch 'Real Jan Brady' T-Shirt - Yellow	The Brady Bunch 'Real Jan Brady' T-Shirt - Yellow
Boris Mark and Jan Hambourg Russian-Born Musicians	The Landing of Jan Van Riebeeck (1619-77) 6th April 1652 1850	Portrait of Jan Pieterszoon Sweelinck 1624	Portrait of Jan Both Engraved by Johannes Meyssens