Philip Lee Wadler (born April 8, 1956) FRS FRSE is an American computer scientist known for his contributions to programming language design and type theory. He is the chair of Theoretical Computer Science at the Laboratory for Foundations of Computer Science at School of Informatics, University of Edinburgh. He has contributed to the theory behind functional programming and the use of monads in functional programming, the design of the purely functional language Haskell, and the XQuery declarative query language. In 1984, he created the Orwell programming language. Wadler was involved in adding generic types to Java 5.0. He is also author of the paper Theorems for free! that gave rise to much research on functional language optimization (see also Parametricity).