Remarks on Wittgenstein’s use of the terms “Sinn”, “sinnlos”, “unsinnig”, “wahr”, and “Gedanke” in the Tractatus

Abstract

In the Tractatus, Wittgenstein makes a tripartite distinction: “The certainty,possibility, or impossibility of a situation is not expressed by a proposition,but by an expression’s being a tautology, a proposition with a sense, or acontradiction” (5.525). In 4.464 Wittgenstein says: “A tautology’s truth iscertain, a proposition’s possible, a contradiction’s impossibile”. Of tautologies Wittgenstein further says that they are senseless, but not nonsensical.They are a sort of extreme cases in the operation with otherwise meaningfulsentences. Wittgenstein does not make a corresponding statement aboutcontradictions – but it appears to be correct to infer that they too are senselessthough not nonsensical. Since a meaningful sentence is neither necessarynor contradictory, it is contingent. This means that it and its negationare both possible. It is important to note that, on the Tractatus view, meaningfulsentences are contingent. This is something which commentatorshave not always clearly observed.