Proof Summary

David Auburn


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Proof Summary

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Proof is a play written by David Auburn. It premiered in May 2000. It tells the story of Catherine, a woman whose father is a brilliant mathematician plagued by mental illness, and her struggle to deal with her suspicion that she has inherited the same disease.

The play begins with Catherine sitting alone in her yard. Her father, Robert, brings her a bottle of champagne wanting to celebrate her twenty-fifth birthday, but she puts him off saying that she has not done anything of note in the field of mathematics. He comforts her and assures her that she will be able to do great things in mathematics if she quits wasting time.

She admits to him her worry that she will inherit his mental illness, something that has prevented him from living a full quality of life. He assures her that this is only a worry of hers, as well. But there is one bad sign—he is dead. He died a week ago.

At this, she wakes up and finds herself on her couch. He disappears as she dozes off again, only to be awakened when Hal leaves the house. Hal is one of Robert’s graduate students, and he has been combing through hundreds of notebooks looking for anything that could be published posthumously. Catherine assures him that it is all nonsense since they were written at the height of her father’s illness.

Hal attempts to flirt with her, which causes her to become suspicious. She demands to see his bag but finds nothing in it. When a notebook falls out of his pocket, she is infuriated and accuses him of stealing her father’s work. She calls the police. He tells her that he was going to return it to her, showing her something written about her during her father’s lucid moment. She begins to cry as she hears sirens.

The next day, her sister Claire arrives and is setting up for brunch. She asks if Catherine will be coming up for Claire’s wedding early. When Catherine demands to know why she is asking all these questions, Claire tells her that the police called asking questions. Catherine tries to explain what happened the night before, but she only comes off as paranoid.

Hal reappears and asks to continue working on her father’s notebooks. Catherine says, yes, and lets him in. Claire hints that Catherine should flirt with Hal, and Catherine storms away.

Claire holds a party at her house with their friends and Robert and Hal’s students, and Catherine is overwhelmed. She escapes to the porch where she finds Hal again. He offers her a beer. As they talk, Hal admits that he does not know if he can contribute to the field of mathematics. Catherine tries to reassure him, and Hal surprises her by kissing her.

He apologizes for trying to take the notebook, and she apologizes for calling the police. They kiss again. He asks if she remembers meeting him years before, and she says, yes. She does, and she recalls that she thought he was “not boring.”

The next day, Hal tells Catherine that he would like to spend the day with her. Claire comes in and tries to convince Catherine to move to New York. She admits that she is selling the house. They argue, each feeling abandoned by the other. Catherine tells Claire that she knows Claire has researched mental hospitals; she believes Claire wants to commit her. Hal comes outside with a notebook containing what he believes is a significant proof.

Act two, flashes back to Catherine telling Robert that she will be leaving for college in a few months. Robert is furious, and they argue. Hal interrupts to present his thesis, and Robert assures him that they will work out the finer points. He apologizes for forgetting Catherine’s birthday and promises to take her out to eat.

We flash forward to where the last act left off. Catherine declares that she wrote the proof but neither believes her. She accuses Hal of being past his prime, saying that she trusted him, and he storms off. She begins to tear up the notebook, but Claire gets it away from her.

We flash back again, and this time, Catherine is telling Robert to come inside. His mind is deteriorating further, and he is belligerent. He reads rambling paragraphs, and in his confusion, he begins to shiver from the cold. He asks her never to leave, and she promises that she will not.

In the final scene, we see Catherine mocking Claire as she prepares to move to New York. Hal comes in saying that the proof checks out and apologizes for not believing her. She tells him to take it because there is no way to say whether she wrote it, but Hal says that they can go over it together. Catherine admits that she does not want to be like her father, and Hal says that maybe she will not be like her father.

The play is a meditation on the way our worst fears about ourselves can cause us to turn on each other. Catherine is talented, but she is so afraid of being like her father that she does not take public credit for the proof. Claire is worried about losing her sister to mental illness, and as such, she makes plans for her without her knowledge. Hal is afraid that he is beyond doing anything mathematically brilliant, and spends his time looking through his late mentor’s work.

While the play is about mathematics, under the surface, it concerns the tensions between the love of people close to us and the things that undo them. Even when we cannot show love fully, in many ways, our family makes choices in our best interest whether we accept it or not.