The laughter thing in argument is interesting. At BHTV there are a few that use it constantly and they come across as very likable people because of it but there is also lack of rigorous thought and defensibility of the POV. Or it is just recognition of the absurd in a very fundamental way, (nihilist)? They would never admit to nihilism but i think this is practice of it.

This is particularly a good watch if someone wanted to do an essay about laughter in argument. http://bloggingheads.tv/diavlogs/15319 (really, watch it. A fundamentalist that believes we should have lots of babies and militarize space so we can build a space elevator and go to mars.) Compare his argument and debate style with Laniers.