 To show (2), Wittgenstein begins by asking (§5), what he takes to be, the central question, namely, “Are there true propositions in Russell’s system, which cannot be proved in his system?”. To address this question, he asks “What is called a true proposition in Russell’s system…?”, which he succinctly answers (§6): “‘p’ is true = p”. Wittgenstein then clarifies this answer by reformulating the second question of (§5) as “Under what circumstances is a proposition asserted in Russell’s game [i.e., system]?”, which he then answers by saying: “the answer is: at the end of one of his proofs, or as a ‘fundamental law’ (Pp.)” (§6). This, in a nutshell, is Wittgenstein’s conception of “mathematical truth”: a true proposition of PM is an axiom or a proved proposition, which means that “true in PM” is identical with, and therefore can be supplanted by, “proved in PM”.