Anne Sjerp Troelstra (born 10 August 1939) is Emeritus professor of pure mathematics and foundations of mathematics at the Institute for Logic, Language and Computation (ILLC) of the University of Amsterdam.He is a constructivist logician, who has been influential in the development of intuitionistic logic. With Georg Kreisel, he was a developer of the theory of choice sequences. He also wrote one of the first texts on linear logic, and with H.