From an interview with the former T.V. host about his undergraduate days at Yale:

Q: To what extent did Yale teach you the art of critical thinking?

DC: Any critical thinking that I got from Yale was in my undergraduate courses, maybe in the true sense of the term, from the great Paul Weiss, Sterling professor of philosophy. Paul Weiss taught his class Socratically, asking to have questions fired at him, and he never failed to take down any five students simultaneously, if he needed to. I later put him on television, on the Jack Paar Tonight Show, and then I had Paul Weiss on my own show, as I did William F. Buckley, [whose] faculty advisor was Paul Weiss.

Weiss, by the way, was the first Jew hired with tenure in philosophy at Yale.  (The episode is described in Neil Gross's biography of Richard Rorty:  basically, Brand Blandshard championed the appointment, but it met with opposition from his anti-semitic colleagues and administrators, but Blandshard prevailed.)  Fifty years on, the former Sterling Professor of Philosophy at Yale is now barely known or read.

(Thanks to Joseph Shieber for the pointer.)

UPDATE:  David Gordon calls to my attention that Prof. Weiss was also on Buckley's TV show.