Math is an exact science. A mathematical proof is a demonstration of this exactness. Math can also be, according to those who study it, beautiful – an art form even; in that sense, Proof is an aptly titled film in which mathematics overlaps with metaphysics, poetry and even faith. Proof knows its characters’ field well enough to have a little fun with it (a character and his math department buddies have a band, and once of their songs is called “i”, as in ‘imaginary number;’ “They just stand there. They don't play anything for three minutes.”); on the other hand, it assumes at times, not ent...