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• It is not enough to have a good mind. The main thing is to use it well. -- Rene Descarte
• Everybody thinks himself so well supplied with common sense that even those most difficult to please.
  . . never desire more of it than they already have. -- Rene Descarte...
• To be possessed of a vigorous mind is not enough; the prime requisite is rightly to apply it.
  -- Descarte...
• I think, therefore I am. -- Rene Descarte
• It is well to know something of the manners of various people
  in order more sanely to judge our own, and that we do not think that everything against our modes is ridiculous, and against reason, as those who have seen nothing are accustomed to think....
• Cogito, ergo sum. (I think, therefore I am) -- Rene Descarte
• I don't think so, said Rene' Descartes. Just then, he vanished.
• Rene Descartes was a drunken fart, `I drink therefore I am.'
• A dirty mind is, well, a wonderful thing.