One day in the late 1940s, Robert Turnbull and I drove to the Minneapolis airport to meet Rudolf Carnap, who was coming to speak to the graduate philosophy club and to visit his good friend Herbert Feigl. At the time, I was discussing his Logische Aufbau in my seminar in Philosophical Analysis, and we had scarcely settled in the car for the return journey when I began to bombard my captive audience with questions. I have long since forgotten the detail of what I was after, but I vividly remember that his first reaction was to expostulate, "But that book was written by my grandfather!"

Sellars, Autobiographical Reflections