Intuitionistic type theory
Introduced by the Swedish philosopher Per Martin-Löf in 1972 as a constructive foundation of
mathematics in the tradition of
Intuitionism,
Intuitionistic Type Theory is at the same time a mathematical language and a
programming language. Central is the identification of propositions and types.
A number of computer proof systems have been based on Intuitionistic Type Theory: NuPRL, LEGO, COQ and others.