Three-valued logic

Hilary Putnam

pp. 99-107

in: Clifford A. Hooker (ed), The logico-algebraic approach to quantum mechanics I, Berlin, Springer, 1975

Abstract

If either component in a disjunction is true (“T”), the disjunction is true; if both components are false, the disjunction is false (“F”); and in all other cases (both components middle, or one component middle and one false) the disjunction is middle (“M”).