Proof is the winner of the 2001 Pulitzer Prize for Drama.
It focuses on Catherine, a young woman who has spent years caring for her father, Robert, a brilliant mathematician in his youth who was later unable to function without her help. His death has brought into her midst both her sister, Claire, who wants to take Catherine back to New York with her, and Hal, a former student of Catherine's father who hopes to find some hint of Robert's genius among his incoherent scribblings. The passion t...