The two main topics here are Brouwer's Berlin lectures and the Vienna lectures. The Berlin lectures were held in 1927 on invitation of the math faculty. Reports tell us that Brouwer made furor in Berlin, students form all over the country flocked to Berlin to hear the mysterious great man. Students called themselves putschists, in reaction to a reaction of Hilbert to Weyl's battle cry "And Brouwer, that is the revolution'. The future for intuitionism looked rosy for a while.A year later Brouwer lectured in Vienna, this was essentially the first public exposition of his philosophy since his dissertation. Wittgenstein attended the lecture, which influenced his return to philosophy.