Proof

by

David Auburn

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Robert Character Analysis

Catherine and Claire’s father, Robert, was a brilliant mathematician and caring dad who also suffered from severe mental illness. At the beginning of the play, Robert has recently died, and a central question is whether he has passed his defining traits—his genius and his illness—onto Catherine, the daughter with whom he was closest. While Robert’s illness is never explicitly diagnosed, his symptoms include hallucinations, delusions, and the compulsion to write huge volumes of nonsense in his notebooks. But the play also depicts his illness as inextricable from his genius: his mind didn’t work like most other people’s, which allowed him to make groundbreaking discoveries in periods of lucidity. Through flashbacks, Robert is shown to be an eccentric, lively, and caring father who takes pride in Catherine’s talents, appreciates her company, and mentors her intellect. He and Catherine were incredibly close, and they lived together for his last few years of life, as she put her own education on hold to care for him. Fittingly, Catherine is a lot like him: she’s also a mathematical genius, she’s prone to mental instability, and she even shares his handwriting.

Robert Quotes in Proof

The Proof quotes below are all either spoken by Robert or refer to Robert. For each quote, you can also see the other characters and themes related to it (each theme is indicated by its own dot and icon, like this one:
Genius and Mental Instability Theme Icon
). Note: all page numbers and citation info for the quotes below refer to the Farrar, Straus and Giroux edition of Proof published in 2001.
Act One, Scene 1 Quotes

ROBERT: You see? Even your depression is mathematical. Stop moping and get to work. The kind of potential you have—

CATHERINE: I haven’t done anything good.

ROBERT: You’re young. You’ve got time.

CATHERINE: I do?

ROBERT: Yes.

CATHERINE: By the time you were my age you were famous.

Related Characters: Robert (speaker), Catherine (speaker)
Page Number: 10
Explanation and Analysis:

CATHERINE: You died a week ago […] You’re sitting here. You’re giving me advice. You brought me champagne.

ROBERT: Yes.

CATHERINE: Which means…

ROBERT: For you?

CATHERINE: Yes.

ROBERT: For you, Catherine, my daughter, who I love very much…It could be a bad sign.

Related Characters: Robert (speaker), Catherine (speaker)
Page Number: 13
Explanation and Analysis:

HAL: […] When your dad was younger than both of us, he made major contributions to three fields: game theory, algebraic geometry, and nonlinear operator theory. Most of us never get our heads around one. He basically invented the mathematical techniques for studying rational behavior, and he gave the astrophysicists plenty to work over too. Okay?

CATHERINE: Don’t lecture me.

Related Characters: Hal (speaker), Catherine (speaker), Robert
Page Number: 17
Explanation and Analysis:

HAL: […] “Talking with students helps. So does being outside, eating meals in restaurants, riding buses, all the activities of ‘normal’ life. Most of all Cathy. The years she has lost caring for me […] her refusal to let me be institutionalized—her keeping me at home, caring for me herself, has certainly saved my life. Made writing this possible. Made it possible to imagine doing math again […] I can never repay her.”

Related Characters: Hal (speaker), Robert (speaker), Catherine
Page Number: 23
Explanation and Analysis:
Act One, Scene 4 Quotes

CLAIRE: Living here with him didn’t do you any good. You said that yourself.

You had so much talent…

CATHERINE: You think I’m like Dad.

CLAIRE: I think you have some of his talent and some of his tendency toward…instability.

Related Characters: Claire (speaker), Catherine (speaker), Robert
Page Number: 45
Explanation and Analysis:
Act Two, Scene 1 Quotes

ROBERT: […] I’m not doing much right now. It does get harder. It’s a stereotype that happens to be true, unfortunately for me—unfortunately for you, for all of us.

CATHERINE: Maybe you’ll get lucky.

ROBERT: Maybe I will. Maybe you’ll pick up where I left off.

CATHERINE: Don’t hold your breath.

ROBERT: Don’t underestimate yourself.

Related Characters: Robert (speaker), Catherine (speaker), Hal
Page Number: 57
Explanation and Analysis:
Act Two, Scene 2 Quotes

CLAIRE: […] You wrote this incredible thing and you didn’t tell anyone?

CATHERINE: I’m telling you both now. After I dropped out of school I had nothing to do. I was depressed, really depressed, but at a certain point I decided, Fuck it, I don’t need them. It’s just math, I can do it on my own. So I kept working here. I worked at night, after Dad had gone to sleep. It was hard but I did it. […]

CLAIRE: Catherine, I’m sorry but I just find this very hard to believe.

Related Characters: Claire (speaker), Catherine (speaker), Robert
Related Symbols: Proof
Page Number: 60-61
Explanation and Analysis:

HAL: I’m a mathematician […] I know how hard it would be to come up with something like this. I mean it’s impossible. You’d have to be…you’d have to be your dad, basically. Your dad at the peak of his powers.

CATHERINE: I’m a mathematician too.

HAL: Not like your dad.

CATHERINE: Oh, he’s the only one who could have done this?

HAL: The only one I know.

Related Characters: Hal (speaker), Catherine (speaker), Robert
Related Symbols: Proof
Page Number: 64
Explanation and Analysis:
Act Two, Scene 3 Quotes

CLAIRE: […] I probably inherited about one one-thousandth of my father’s ability. It’s enough.

Catherine got more, I’m not sure how much.

Related Characters: Claire (speaker), Robert, Catherine
Page Number: 68
Explanation and Analysis:
Act Two, Scene 4 Quotes

CATHERINE: “[…] In September the students come back and the bookstores are full. Let X equal the month of full bookstores. The number of books approaches infinity as the number of months of cold approaches four. I will never be as cold now as I will in the future. The future of cold is infinite. The future of heat is the future of cold. The bookstores are infinite and so are never full except in September…” […] It’s all right. We’ll go inside.

ROBERT: I’m cold.

CATHERINE: We’ll warm you up.

ROBERT: Don’t leave. Please.

CATHERINE: I won’t. Let’s go inside.

Related Characters: Catherine (speaker), Robert (speaker)
Page Number: 74
Explanation and Analysis:
Act Two, Scene 5 Quotes

HAL: […] Your dad dated everything. Even his most incoherent entries he dated. There are no dates in this.

CATHERINE: The handwriting—

HAL: —looks like your dad’s. Parents and children sometimes have similar handwriting, especially if they’ve spent a lot of time together.

Related Characters: Hal (speaker), Catherine (speaker), Robert
Related Symbols: Proof
Page Number: 80
Explanation and Analysis:

HAL: There is nothing wrong with you.

CATHERINE: I think I’m like my dad.

HAL: I think you are too.

CATHERINE: I’m…afraid I’m like my dad.

HAL: You’re not him.

CATHERINE: Maybe I will be.

HAL: Maybe. Maybe you’ll be better.

Related Characters: Hal (speaker), Catherine (speaker), Robert
Page Number: 82
Explanation and Analysis:
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Robert Character Timeline in Proof

The timeline below shows where the character Robert appears in Proof. The colored dots and icons indicate which themes are associated with that appearance.
Act One, Scene 1
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
...sits in a chair on the back porch of a house in Chicago. Her father, Robert, stands behind her, but she doesn’t realize that he is there. It’s nighttime, and both... (full context)
Genius and Mental Instability Theme Icon
Proof, Trust, and Credibility Theme Icon
When Catherine asks Robert why he’s there, he says he’s “check[ing] up” on her. Catherine is waiting for his... (full context)
Family and Heredity Theme Icon
Since it is past midnight, Robert gestures toward a bottle of champagne while wishing Catherine a happy birthday. As she pops... (full context)
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
Robert asks Catherine what she will be doing on her birthday, and she says that she’ll... (full context)
Genius and Mental Instability Theme Icon
Caretaking and Sacrifice Theme Icon
Confused, Robert says that he thought that Claire was coming. But Catherine explains that Claire is arriving... (full context)
Genius and Mental Instability Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine insists that she’s not lazy—she’s been busy taking care of Robert. But Robert enumerates her bad habits: she sleeps late, eats poorly, doesn’t work, doesn’t clean,... (full context)
Genius and Mental Instability Theme Icon
When Catherine admits that she has “lost a few days,” Robert sharply asks how many—he knows that she counts them. Catherine claims not to keep track,... (full context)
Genius and Mental Instability Theme Icon
But Robert says that if each day were a year, the number would be quite interesting. Catherine... (full context)
Family and Heredity Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine feels that she hasn’t “done anything good,” particularly in comparison to Robert, who was already famous when he was her age. He confirms that by 25, he’d... (full context)
Genius and Mental Instability Theme Icon
Robert felt an amazing clarity after getting sick, and Catherine asks whether he was happy then.... (full context)
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine abruptly asks when “it” started. As Robert explains that he was in his mid-twenties, he realizes that this is what Catherine may... (full context)
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
Robert reassures Catherine that she’s just going through a rough spot and, if she just “get[s]... (full context)
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
Catherine seems to believe Robert, but then she interrupts him: his argument doesn’t make sense. He just called himself “crazy,”... (full context)
Genius and Mental Instability Theme Icon
Hal enters the room, startling Catherine. As he apologizes for staying so late, Robert disappears. Noticing Catherine’s champagne bottle, Hal asks whether she is drinking alone. She says yes... (full context)
Proof, Trust, and Credibility Theme Icon
...another week to go through everything in the office. So far, he’s been sorting the notebooks—Robert dated them all. But when Hal suggests that he bring the books home, Catherine refuses.... (full context)
Proof, Trust, and Credibility Theme Icon
...during his Ph.D. program. That was a few years back, during a “lucid year” that Robert had. Hal adds that if he could do even a fraction of the work Robert... (full context)
Proof, Trust, and Credibility Theme Icon
...out of the house like Catherine suspects. Still, she accuses Hal of taking notebooks from Robert’s office in hopes of stealing Robert’s work to advance his own career. Hal swears this... (full context)
Genius and Mental Instability Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine interrupts, saying that she lived with Robert—since her mom died, she’s the one who had to watch him descend into madness. He... (full context)
Sexism Theme Icon
Suddenly, Catherine says that she will be the one to look through the books; Robert was her father, after all. But Hal says she doesn’t have the skills required to... (full context)
Genius and Mental Instability Theme Icon
Proof, Trust, and Credibility Theme Icon
...say that he borrowed the notebook not because of any math, but because of something Robert wrote about Catherine. As he starts to read, Catherine hangs up the phone. (full context)
Sexism Theme Icon
Proof, Trust, and Credibility Theme Icon
Robert wrote that it was “a good day,” since Catherine had some good news—Hal doesn’t know... (full context)
Caretaking and Sacrifice Theme Icon
In the rest of the entry, Robert writes that he feels better when talking to students and doing “all the activities of... (full context)
Act One, Scene 2
Proof, Trust, and Credibility Theme Icon
Caretaking and Sacrifice Theme Icon
Cautiously, Claire asks Catherine how she is feeling about Robert’s death, but Catherine doesn’t elaborate beyond saying she’s fine. When Claire asks what she will... (full context)
Act One, Scene 3
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
...she asks him about his research. His work discourages him; it will never compare to Robert’s work. But Catherine reminds him that her father had to labor away at problems just... (full context)
Proof, Trust, and Credibility Theme Icon
...always liked Catherine, even just from glimpsing her at a distance when she would visit Robert. They kiss again, and Catherine asks Hal if he remembers visiting the house four years... (full context)
Act One, Scene 4
Proof, Trust, and Credibility Theme Icon
...She gives the chain to Hal; he can use it to open a drawer in Robert’s office. After Hal leaves, she smiles, privately excited. (full context)
Caretaking and Sacrifice Theme Icon
...is trying to help and wants to make up for having left Catherine alone with Robert for so many years, but Catherine bitterly asks why she’s trying to “help” now instead... (full context)
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Caretaking and Sacrifice Theme Icon
Nonetheless, Claire believes an institution would have helped Robert more, and also that Catherine may have “been better” in that scenario. Catherine demands to... (full context)
Act Two, Scene 1
Proof, Trust, and Credibility Theme Icon
It’s a September afternoon, four years earlier. Robert is sitting on the porch, an unopened notebook next to him. Catherine silently steps onto... (full context)
Family and Heredity Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine abruptly tells Robert that she’s going to start school at the end of the month at Northwestern. He... (full context)
Proof, Trust, and Credibility Theme Icon
Caretaking and Sacrifice Theme Icon
But Robert questions Catherine’s choice to move (he says it’s a “big step”) and whether she can... (full context)
Proof, Trust, and Credibility Theme Icon
...to answer it. She returns to the porch with Hal, who is carrying an envelope. Robert informs Hal that he came at a terrible time, as he and Catherine are arguing.... (full context)
Proof, Trust, and Credibility Theme Icon
Caretaking and Sacrifice Theme Icon
Hal awkwardly suggests that he come back at a different time, but Robert tells him to stay and insists that they will give their argument a break and... (full context)
Family and Heredity Theme Icon
Caretaking and Sacrifice Theme Icon
Hal gives Robert the envelope, which he says is only a draft. Robert congratulates him and promises they’ll... (full context)
Proof, Trust, and Credibility Theme Icon
Caretaking and Sacrifice Theme Icon
...When Catherine is uncomfortable, Hal gets embarrassed and tries to take back his comment. But Robert says that it’s great for Catherine to leave and jokes that he can’t wait to... (full context)
Family and Heredity Theme Icon
When Hal asks Robert if he’s working on anything, Robert says no and adds that he’s glad to have... (full context)
Family and Heredity Theme Icon
Catherine says that Robert may “get lucky,” but he replies that perhaps she will “pick up where [he] left... (full context)
Proof, Trust, and Credibility Theme Icon
Caretaking and Sacrifice Theme Icon
Catherine assures Robert that it’s okay. He tells her that he will take her out to eat and... (full context)
Act Two, Scene 2
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
...she got depressed after she had to drop out of school to take care of Robert. (full context)
Genius and Mental Instability Theme Icon
Proof, Trust, and Credibility Theme Icon
Claire doesn’t believe Catherine, because it’s written in Robert’s handwriting. Catherine asks Hal to confirm that it is actually her handwriting and not her... (full context)
Sexism Theme Icon
Proof, Trust, and Credibility Theme Icon
...tells Catherine to go over the proof with Hal. But Hal raises the possibility that Robert went over it with Catherine before he died. He suggests that he take it to... (full context)
Sexism Theme Icon
Proof, Trust, and Credibility Theme Icon
...know.” She claims again that she wrote it, but he says that it’s written in Robert’s handwriting. Catherine quietly insists that her handwriting looks similar to her father’s. (full context)
Family and Heredity Theme Icon
Sexism Theme Icon
Proof, Trust, and Credibility Theme Icon
...she told. When she asks if he wants to test her handwriting, he replies that Robert could have dictated it to her. As a mathematician, he “know[s] how hard it would... (full context)
Act Two, Scene 3
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
...she, a currency analyst, is pretty good with numbers—but she has only a fraction of Robert’s genius. Catherine is more gifted, although Claire isn’t sure how gifted. (full context)
Act Two, Scene 4
Genius and Mental Instability Theme Icon
Proof, Trust, and Credibility Theme Icon
It’s December, about three-and-a-half years earlier. On the porch, Robert is wearing a t-shirt and writing in a notebook. Catherine steps outside wearing a winter... (full context)
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Robert then announces that “The machinery is […] on full-blast”—his mind is working creatively, like it... (full context)
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Robert confesses that he had been terrified that he would never be able to work like... (full context)
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Proof, Trust, and Credibility Theme Icon
Now that his mind is working again, Robert tells Catherine that the two of them can work together. He selects one of the... (full context)
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Caretaking and Sacrifice Theme Icon
Robert refuses to go inside until they talk through the proof, so Catherine begins to read... (full context)
Act Two, Scene 5
Sexism Theme Icon
Proof, Trust, and Credibility Theme Icon
...father’s name, or even his own. But Hal tells her that he doesn’t think that Robert wrote the proof after all; it uses some recently developed mathematical techniques, ones that Robert... (full context)
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
Catherine replies that Robert could have read about the newer techniques. Hal admits that it’s possible, but that the... (full context)
Genius and Mental Instability Theme Icon
Family and Heredity Theme Icon
Proof, Trust, and Credibility Theme Icon
...her that there’s nothing wrong with her, Catherine admits that she’s afraid she is like her father , to which he responds that she is “not him […] Maybe [she]’ll be better.”... (full context)
Genius and Mental Instability Theme Icon
Proof, Trust, and Credibility Theme Icon
...that writing the proof was like “connecting the dots.” She never worked on it with Robert, although sometimes she’d watch television with him in the middle of the night when she... (full context)