Freges Kriterien der Sinngleichheit

Abstract

Abstract: Frege’s mature writings apparently contain two different criteria of sense identity. While in „Über Sinn und Bedeutung“ (1892) and in „Kurze Übersicht meiner logischen Lehren“ (1906?) Frege seems to advocate a psychological criterion, his letter to Husserl of December 12, 1906 offers a thoroughly logical criterion of sense identity. It is argued that the latter proposal is not a „momentary aberration“, but rather Frege’s official criterion; his psychological criteria only serve as a way of illustrating questions of sense identity by appealing to the thoughts of ideal thinkers.