"Wed. evg." "—This raised a lot of complicated problems, which we were in the middle of when an unknown German appeared, speaking very little English but refusing to speak German. He turned out to be a man who had learnt engineering at Charlottenburg, but during his course had acquired, by himself, a passion for the philosophy of mathematics, and has now come to Cambridge on purpose to hear me. This took till 5.15;...."

Russell wrote (presumably later) up the left margin of the page by this paragraph: "This was Wittgenstein". [Perhaps the annotation dates from #441. (q.v.), record 17538.]