In my opinion, this play has a few themes. The first theme: Do not underestimate people. Hal and Claire did not believe Catherine when she said she wrote the "Proof" because she did not have a college degree. Since the handwriting looked like Robert's writing, they thought he had written it. Catherine was underestimated. Hal and Claire neglected to look at the fact that Catherine had the same math ability as her Dad, Robert. She did not need a degree.…