Who said it: Owen Wilson in The Darjeeling Limited (2007)
Argument: Over politics.

When someone's fiery passion about domestic fracking erupts into loogies traveling dangerously close to your face, it's time to end the conversation. Shoot, you're not even sure how you got in the middle of the debate in the first plae. You're just trying to play Grand Theft Auto while your faux-activist friend and genuine Romney supporter friend duke it out nearby.