Let us finally say something about two deaths: the murder that justifies the title of the book we have been discussing, "The Murder of Professor Schlick," and four decades later the mental-illness driven death of the mathematician/logician Kurt Godel. On the morning of June 22, 1936, Schlick was due to present his final lecture of the semester to his class at Vienna University. He took Tram D and arrived at the University at 9:15. He walked through the iron gate, down the hall, and turned right onto a staircase. Students in Room 41 were waiting for him. He must have walked right past Johann Nelbock on his way. Nelbock, a mentally unhinged student, had become extremely agitated by a lecture Schlick had given on immortality earlier in the semester. (For the positivists, there was a puzzle as to whether the claim of immortality was even meaningful.) After Schlick walked past him, Nelbock ran forward to get ahead of Schlick, turned around and fired four ...