Frege’s Influence on the Thesis of the Determinacy of Sense in Wittgenstein’s Tractatus

Wittgenstein introduces the notion of blurred boundaries (verschwommen Ränder) in the Investigations (e.g., IF §71) as a critical response to Frege’s spatial metaphor of a logically genuine concept (Begriff) having sharply defined boundaries. However, this metaphor and the Principle of Completeness for a concept’s logical definition in §56 of Frege’s Grundgesetze der Arithmetik was highly significant in the Tractarian commitment to the thesis of the Determinacy of Sense (der Bestimmtheit des Sinnes) expressed by TLP 3.23. This presentation therefore explores this influence by focusing first on the Fregean notion of concept in terms of the relationship between the function-object logical structure and the sense-meaning semantic structure. On the other hand, this work in progress finally analyses the main critical views from Wittgenstein’s early philosophy to Frege´s differentiation between sense (Sinn) and meaning (Bedeutung) and what it is for a proposition to have a fully determined sense in Wittgenstein’s Tractatus.