Complete-review.com has collected snippets from reviews of significant productions:

• "(A) wonderful drama that elegantly describes the world of mathematics, and suggests how ill-suited the mathematical notion of truth is for life. It's impossible to divine the future, and it's no easier to derive it. We're only as certain as our next best guess." - Daniel Rockmore, Chronicle of Higher Education

• "(A)n exciting new drama (.....) This play by David Auburn combines elements of mystery and surprise with old-fashioned storytelling to provide a compelling evening of theater." - David Kaufman, Daily News

• "Whatever its flaws, Auburn has created a great part, which Paltrow fills to overflowing. (...) But not even she can camouflage the weak point in Auburn's play: that we never know what the crucial theory is. For me, it is a defining moment in modern American drama when Claire at last asks Hal, "Can you tell me what the proof is ?" and the two of them walk off stage busily talking." - Michael Billington, The Guardian

• "The play wants to contrast the inductive, tightly logical proofs possible in mathematics with the indeterminacy of attempts to prove things in the real world where leaps of faith may be necessary. But it blows its chances on both levels." - Paul Taylor, The Independent

• "Proof is David Auburn's first major production; and if it is not exactly the brilliant debut that some have been claiming, it certainly represents the work of a writer with a fairly decent grasp on his not terribly fanciful material. (...) (W)hat makes this play problematic is not its author's ignorance regarding prime numbers. It is the thinness of his plot. He runs out of material so quickly that, by the middle of the second act, the play jerks to a halt and starts running in place." - Robert Brustein, The New Republic

• "Here, those of us who want their dramatic characters to be real people need not feel excluded. (...) All four -- whether loving, hating, encouraging or impeding one another -- are intensely alive, complex, funny, human. (...) Out of this curious quartet, Auburn creates emotionally and intellectually enveloping music." - John Simon, New York

• "But my relief that David Auburn's Proof is less about its ballyhooed higher mathematics than the fragility of life and love was matched by my delight in his fine and tender play. (...) Proof surprises us with its aliveness and intelligent modesty, and we have not met these characters before." - John Heilpern, The New York Observer

• "The play is beautifully and closely plotted. OK, the story itself is not much more than a highbrow soap opera with painless references to mathematics. Yet Auburn, in his first Broadway outing, provides characters behaving credibly and natural dialogue without a single stagy phrase stumbling the flow and also ensures the tension is handsomely sustained." - Clive Barnes, The New York Post

• "Without any baffling erudition -- if you know what a prime number is, there won't be a single line of dialogue you find perplexing -- the play presents mathematicians as both blessed and bedeviled by the gift for abstraction that ties them achingly to one another and separates them, also achingly, from concrete-minded folks like you and me. And perhaps most satisfying of all, it does so without a moment of meanness." - Bruce Weber, The New York Times
  "What's perhaps most striking about Auburn's writing, though, is his sense of structure, which is at once imaginative and stringently coherent. Veering gracefully from past to present and from reflection to confrontation, the playwright traces the development of his characters and plot with a scientist's preciseness and a poet's lyricism." - Elysa Gardner, USA Today

• "Nearly every scene is based on a piece of information cunningly withheld until the last moment; and unlike playwrights who take such strategic games in ponderous earnest, Auburn perceives their essential playfulness, as do his characters, who toy with each other much as he toys with them and with us. It's impossible to resent manipulation that's carried on in such a generous spirit; by its uninsistent acceptance of its own shallowness, it opens out into a vision of reality." - Michael Feingold, The Village Voice

• "Mr. Auburn's brainiacs hail from the Hollywood school of genius. That's where highly photogenic people learn how to make Einsteinian breakthroughs without the benefit of a fancy degree while watching the late-late show on TV. Call it the Good Will Hunting principle of brain power, in which a hero's brilliance can be measured in direct proportion to his or her kissability and sulky disregard for higher education. (...) Proof is lively indeed, the jokes about prime numbers notwithstanding. It's also rather shallow, the jokes about prime numbers notwithstanding." - Amy Gamerman, Wall Street Journal