Intensional expressions

Kazimierz Ajdukiewicz

pp. 96-125

in: Jerzy Pelc (ed), Semiotics in Poland 1984–1969, Berlin, Springer, 1979

Abstract

Intensional expressions can both be expressions containing free variables and expressions which do not contain such variables. The expression E, which contains no free variables, is an intensional expression if it can be transformed into a non-equivalent expression E" by replacing one of its members by an expression which is equivalent to that member.