I think there are three steps to writing a script. First, you have to have a theme, something you want to say. It doesn’t have to be a particularly great thing, but you have to have something that’s bothering you. In the case of Taxi Driver, the theme was loneliness. Then you find a metaphor for that theme, one that expresses it. In Taxi Driver, that was the cabbie, the perfect expression of urban loneliness. Then you have to find a plot, which is the easiest part of the process. All plots have been done; they’re fairly easy, you just work through all the permutations until the plot accurately reflects the theme and the metaphor. You push the theme through the metaphor and you should come out with the plot.
- Paul Schrader