Allows for multiple interpretations

The few people out there who bastardize the term "multilayeredness" usually when speaking about some rather lame sci-fi film, would do well in watching this movie and realize what real multilayeredness is. In spite of the simplicity of the storyline - or maybe because of it - Duel allows for different readings, for instance:

1. David Mann represents mankind, the truck is every possible catastrophe or desaster that comes in the way - war, diseases, earthquakes, climate change ...-.
2. The fight between car and truck is an allegory for every possible situation, where the strong and powerful abuse the weak and small, be it a war between nations, economic struggle, corporations and consumers, bosses and workers, adults and children, men and women....
3. A movie about attitude in life; a guy thinks that the best way of dealing with problems is fleeing away from them. When he is finally forced to turn around and, literally, confront the problem face to face, he is able to solve it.
4. A Nietzschean parable about the narcotic effects of social life on the primary animal instincts; Mann´s natural instincts of survival have been dampened by the conventions of society, the luxury of modern life and overreliance in tools and technology. When he learns to get rid of the tools - the car - and the conventionalisms of society - the briefcase with his name in it - he is ready to deal with the menace.
5. Finally, my favourite interpretation - and the one that is more hinted at by the script -; the truck symbolizes Mann´s inability to live up to the expectations that society puts on men in general and on him in particular. Notice his wife´s insatisfaction with him, because he had failed to defend her the day before, the double meaning of the dialog about the radiator hose or that guy in the radio programm and his doubts about being called "head of the family". Also observe that when he enters the cafe he doesn´t ask for the restroom; his questions is "Can I go to the men´s room?".