Computer scientist and applied category theorist, 28th June 1941 – 3rd July 2006. His theoretical work includes the algebraic theory of abstract data types, initial model semantics, institutions, order sorted algebra, parameterized programming, database integration, hidden algebra, sheaf semantics of interacting objects, and algebraic semiotics. Very important to computer science was his rôle in founding algebraic specification, including abstract data types, modules and module composition, and the OBJ language family. Goguen wrote A Categorical Manifesto, which tried to encourage the use of category theory in computer science.