Bill O'Reilly clashed with David Letterman during his appearance on The Late Show Friday night. Letterman took O'Reilly to task for his over-simplified views and "bonehead" remarks.

Letterman questioned the legitimacy of O'Reilly's network, Fox News, asking "You guys over there at Fox, and guys like Rush Limbaugh, you guys know it's all just a goof, right? You're just horsing around. Am I right about that? You're doing it because you know it'll be entertaining."

As the Huffington Post reported...