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Proof | Introduction

Proof (2001), a play by David Auburn, won the Pulitzer Prize in 2001, as well as several other major awards for drama. The play is set in Chicago, where Robert, a former genius of a mathematician who suffered from mental illness, has recently died. Robert appears in the play talking with his daughter Catherine, a depressed college drop-out who stayed at home and cared for her father over the last few years of his life. As preparations are made for the funeral and Catherine’s sister Claire returns from New York, Catherine forms a tentative friendship with Hal, a mathematician who is one of her father’s former students.

The plot moves into high gear when Hal discovers in one of the notebooks that Robert left behind a proof of a mathematical theorem that mathematicians had thought impossible. It is a sensational discovery, but Catherine stuns Hal by claiming she wrote the proof. But did she? The handwriting in the notebook looks very like her father’s. As the mystery develops and resolves, the playwright explores issues such as what the link may be between genius and madness and whether either or both can be inherited. But Proof is also a story about human relationships, suggesting that developing trust and love can be as difficult, and just as uncertain, as establishing the truth of a mathematical proof.

Proof Summary

Act 1, Scene 1
Proof begins at one o’clock in the morning on the porch of a house in Chicago. Catherine sits in a chair, exhausted, and is startled when she realizes her father, Robert, is there. Robert gives her a bottle of champagne and wishes her happy birthday. He wants her to celebrate her birthday with friends, but she says she has none. Robert expresses concern about her, saying that she sleeps until noon, eats junk food, and does not work. He tells her to stop moping. She has potential and there is still time. It transpires that Robert did his best work by the time he was in his mid-twenties. After that, he became mentally ill. Catherine is worried that she will inherit the illness.

It then transpires that Robert died a week before, of heart failure, and the funeral is the next day.

Hal, a former student of Robert’s, enters. He has been working on Robert’s notebooks, but Catherine says there is nothing valuable in them. Hal invites her to hear him play in a rock band, but she is not interested. He speaks about how he admired her father, who helped him through a difficult period in his doctoral studies. This was four years ago, when Robert’s illness went into remission. Catherine, fearing that Hal may be taking one of her father’s notebooks from the house without permission, demands to see his backpack. She finds nothing there, but as he is about to leave, a notebook falls from his jacket pocket. She accuses him of stealing it and calls the police. He protests that in the notebook, Robert wrote something appreciative about Catherine on her birthday four years ago. Hal was going to wrap the notebook and give it to her.

Act 1, Scene 2
The next morning, Catherine and Claire, who has arrived from New York, are drinking coffee. Claire tries to be kind, but Catherine is not receptive. Claire quizzes Catherine about Hal and about why she called the police, but Catherine resents the questioning. Hal enters unexpectedly, and there is a moment of confusion as Catherine berates her sister. Hal quickly exits, leaving Claire saying that decisions must be made. She wants Catherine to stay with her in New York.

Act 1, Scene 3
That night, there is a party following the funeral. Catherine is on the porch when Hal, who has been playing in the band, approaches her. He compliments her on her dress and talks about... » Complete Proof Summary