Malcolm Gladwell's Blink
talks about how we make snap decisions -- how often they're dead on, and the situations in which they're not. He moves gracefully from a psychologist who can tell in 15 minutes if a couple will stay married for the next 15 years to the Amadou Diallo shooting to the election of Warren Harding (who looked
like a president even if he wasn't good at it) to the failure of New Coke. I have no idea if it will help you in your screenwriting or even in your life, but boy, what a fascinating book.
Erudition, yes, that's
the word I was looking for!