Formalization of a scholastic solution of the paradox of the "liar"

Joseph Bocheński

pp. 64-66

in: Albert Menne (ed), Logico-philosophical studies, Berlin, Springer, 1962

Abstract

Paulus Venetus ¹ (died 1429) enumerates no fewer than fourteen distinct solutions of the paradox of the "Liar"² of which one corresponds precisely to the modern; the author nevertheless declines all of them and offers another, the fifteenth. This solution comes about from the distinction of two modes of meaning: (a) the meaning (significatio) with no further determination, (b) the "precise and adequate" meaning (significatio vraecisa et adaequata). A proposition means in the first place precisely what it means and nothing else; in the second place, it means also that it is itself true.