Time to pull an old sig out of the archive. The quote is a paraphrase of
something Marvin Minsky wrote.
-------------------------------+-----------------------------------------------
Sean Morgan (sean@lucifer.com) | "If instead we were computer-simulated beings
                               | in a computer-simulated universe you wouldn't
http://www.lucifer.com/~sean/  | be able to tell -- except that nuclear physics
                               | would show round-off errors not unlike the
                               | uncertainty principle."  Uh, wait a minute ...