A Logic for Parametric Polymorphism

Abstract

In this paper we introduce a logic for parametric polymorphism. Just as LCF is a logic for the simply-typed -calculus with recursion and arithmetic, our logic is a logic for System F. The logic permits the formal presentation and use of relational parametricity. Parametricity yields—for example—encodings of initial algebras, final co-algebras and abstract datatypes, with corresponding proof principles of induction, co-induction and simulation.