David Mann: I'd like to report a truck driver who's been endangering my life.
David Mann: That truck driver's crazy, he's been trying to kill me, I mean it.
Bus Driver: Well, mister, if I was to vote on who's crazy around here, it'd be you.
David Mann: Well it's about time, Charlie.
David Mann: Come on, car! come on, LET'S GO.
David Mann: Fill it with Ethel.
Gas Station Attendant: As long as Ethel doesn't mind.
David Mann: You can't beat me on the grade. You can't beat me on the grade.
David Mann: Come on you miserable fat-head, get that fat-ass truck outta my way.
David Mann: Where's the summit? Please... please... come ooooon.
Answer: As the title indicated this became a "duel." Once challenged, David got pulled into a fight mentality with the crazed truck driver to where his "road rage" pushed aside all logic and sense of safety. David became obsessed with defeating the "Goliath" opponent. Also, if he turned around and went home, that would have ended the movie.
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