I found it delightful to see a real philosopher on The Daily Show. And I was pleased to see that Stewart was smart enough to have genuine respect for a genuinely erudite and wise man like Frankfurt.
For those of you who didn't have to read any Frankfurt essays in grad school, he is a philosopher of unusual sensitivity, creativity, subtlety, and depth. He is most well known for his work on free will, especially his famous thought experiment designed to show that the openness of alternative possibilities is not a necessary condition for freedom. Frankfurt's work on the structure of the self, and the relation between higher and lower order aims and desires, is central to contemporary discussion of the nature of agency. And Frankfurt's ideas about care and love as sources of normativity I find to be more satisfactory than almost all the alternatives.
If you're one of those people who thinks that contemporary analytic philosophy is obscure, scholastic, and irrelevant to real human concerns, you need to read Harry Frankfurt.
Here's an interview with Frankfurt on “the necessity of love.” [.pdf]
And here you can see video of Frankfurt in his natural habitat giving a lecture on “Some Mysteries of Love” at UC Riverside in 2000. [Realplayer]
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