Steven Spielberg's new film, "Minority Report," is not exactly a deep take on the problems of "knowing," but since you'll probably see it anyway, here's where it brought me.
The film, based on a science fiction story by Philip K. Dick, argues that the future can indeed be known. Moreover, our security depends upon finding a Pinchas, a zealot who knows what crimes are being committed, and personally stops them. So anxious are we to hire this Pinchas, this future-knower, that we would sacrifice our freedoms for him.
It is 2054 in a dark, police-state Washington, D.C, all murder has been foretold by three mermaid-type creatures called precogs, so named because they have pre-cognition. The crimes are prerecorded in the future, then replayed in real time, at which point they are interrupted and prevented by a precrime squad headed by John Anderton (Tom Cruise), the very Pinchas we are seeking. Pretty neat.