Los Angeles Times
It is a brilliant intellectual adventure that fans of bold independent filmmaking will want to experience, even though the ending is something of a letdown.
A triumph of low-end production design, shot in sizzling, solarized black and white, and driven by a propulsive, insinuating score, Pi is a horror movie that makes you think and an indie film that makes you squirm.
The A.V. Club
Aronofsky's ability to capture the rush and confusion of racing down a timeline toward infinity, only to suddenly slam into a dead end, makes for impressive and occasionally disturbing stuff.
The seductive thing about Aronofsky's film is that it is halfway plausible in terms of modern physics and math.
San Francisco Chronicle
It proceeds, weirdly enough, from the truly annoying to the absolutely fascinating.
San Francisco Examiner
Pi will not be for everyone, but for those who are fed up with the mainstream idiocy that gets dumped into theaters each summer, this movie willbe like a great big palate-clearing taste of sorbet.
The movie's freakazoid intensity gets to you, but there's something at once cramped and show-offy in Aronofsky's refusal to even slighty vary its atmosphere of shock-corridor burnout.
The film's imaginative, diverse images create a mind's-eye urban claustrophobia; such intensity may exhaust over 85 minutes' course, but it's never less than impressive.
Pi may be the most engrossing piece of cyberpunk cinema yet.
With this odd mixture of elements the film's tone is gloomy, portentous, and hysterical, yet at the same time strangely earnest and square, as if David Lynch had tried to somehow make a movie version of Scientific American.