Who was Jan Łukasiewicz?

Jan Łukasiewicz was a Polish logician who contributed much to the study of Mathematical Logic. He was able to show that the Symbolic Logic that is taken as an introductory class by philosophy students is both consistent and complete. (Consistent means that there are no contradictions. Complete means that every true statement can be proved.)

There were other logicians who lived about the same time as Łukasiewicz and also deserve recognition for their contributions to logic, mathematics, and philosopy. Among these are Gottlob Frege, Ernst Zermelo, Bertrand Russell, Rudolf Carnap, Abraham Fraenkel, Alfred Tarski, Kurt Gödel, and Willard Van Quine. (In fact, one reference states that the four greatest logicians of all time were Aristotle, Gottlob Frege, Alfred Tarski, and Kurt Gödel. Another reference states that the two most important logicians of the 20th century were Bertrand Russell and Kurt Gödel.)

However, Jan Łukasiewicz deserves a special recognition for another reason as well, and that is for a way of writing algebraic expressions, known today as the Polish Notation--something with which all students of Computer Science become familiar.