Proof

Act One

Scene 1

Proof opens on the back porch of a home in Hyde Park, Chicago, very late at night. Robert points out to his daughter, Catherine, that it is past midnight and thus it is now her twenty-fifth birthday. They celebrate by toasting with champagne. Robert and Catherine reminisce about her childhood. Robert suggests to Catherine that if she can’t sleep, perhaps she should do some mathematics, an idea that Catherine vehemently dismisses. Robert calls her lazy, expressing concern about Catherine’s apathy, her sleep habits, and her hygiene. She admits that she’s “lost a few days.” At first she says she doesn’t know how many days she has “lost” by sleeping through them, but Robert knows his mathematically-minded daughter too well, and challenges her, “I bet you count.” Catherine admits to losing thirty-three and a quarter days to depression. She despairs that she hasn’t “done anything good.” Robert dismisses her worries — but Catherine points out to him that by her age