Eulogy: Alfred Tarski, 1901-1983

Of his numerous investigations, outlined in seven books and more than 300 other publications, Tarski was most proud of two: his work on truth and his design of an algorithm in 1930 to decide the truth or falsity of any sentence of the elementary theory of high school Euclidean geometry. Today this is viewed as a pioneering, landmark result in the burgeoning branch of theoretical computer science which considers what problems can or cannot be settled, either practically or in principle, by computers.