 There are, first, the propositions of logic itself. These do not represent states of affairs, and the logical constants do not stand for objects. “My fundamental thought is that the logical constants do not represent. That the logic of the facts cannot be represented” (TLP 4.0312). This is not a happenstance thought; it is fundamental precisely because the limits of sense rest on logic. Tautologies and contradictions, the propositions of logic, are the limits of language and thought, and thereby the limits of the world. Obviously, then, they do not picture anything and do not, therefore, have sense. They are, in Wittgenstein’s terms, senseless (sinnlos). Propositions which do have sense are bipolar; they range within the truth-conditions drawn by the truth-tables. But the propositions of logic themselves are “not pictures of the reality … for the one allows every possible state of affairs, the other none” (TLP 4.462). Indeed, tautologies (and contradictions), being senseless, are recognized as true (or false) “in the symbol alone … and this fact contains in itself the whole philosophy of logic” (TLP 6.113).