 There is little doubt that Wittgenstein was invigorated by L.E.J. Brouwer’s March 10, 1928 Vienna lecture “Science, Mathematics, and Language” (Brouwer 1929), which he attended with F. Waismann and H. Feigl, but it is a gross overstatement to say that he returned to Philosophy because of this lecture or that his intermediate interest in the Philosophy of Mathematics issued primarily from Brouwer’s influence. In fact, Wittgenstein’s return to Philosophy and his intermediate work on mathematics is also due to conversations with Ramsey and members of the Vienna Circle, to Wittgenstein’s disagreement with Ramsey over identity, and several other factors.