Discourse on the Method

The Discourse on the Method is a philosophical and autobiographical treatise published by René Descartes in 1637. Its full name is Discourse on the Method of Rightly Conducting One's Reason and of Seeking Truth in the Sciences (French title: Discours de la méthode pour bien conduire sa raison, et chercher la vérité dans les sciences). The Discourse on The Method is best known as the source of the famous quotation "Je pense, donc je suis" ("I think, therefore I am"), which occurs in Part IV of the work. (The similar statement in Latin, Cogito ergo sum, is found in Part I, §7 of Principles of Philosophy.)

• Of all things, good sense is the most fairly distributed: everyone thinks he is so well supplied with it that even those who are the hardest to satisfy in every other respect never desire more of it than they already have. (fr; en)
  • Part 1
  • Variants:
    • Good sense is of all things in the world the most equally distributed, for everybody thinks he is so well supplied with it, that even those most difficult to please in all other matters never desire more of it than they already possess.
    • Common sense is the best distributed commodity in the world, for every man is convinced that he is well supplied with it.
    • Nothing is more fairly distributed than common sense: no one thinks he needs more of it than he already has.

• Car ce n'est pas assez d'avoir l'esprit bon, mais le principal est de l'appliquer bien. [1]
  • Translation: It is not enough to have a good mind. The main thing is to use it well.
  • Part 1

• The greatest minds, as they are capable of the highest excellencies, are open likewise to the greatest aberrations; and those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, while they run, forsake it.
  • Part 1
  • Variants:
    • The greatest minds are capable of the greatest vices as well as of the greatest virtues.

• The first precept was never to accept a thing as true until I knew it as such without a single doubt.
  • Part 2

• Divide each difficulty into as many parts as is feasible and necessary to resolve it.
  • Part 2

• The last rule was to make enumerations so complete, and reviews so comprehensive, that I should be certain of omitting nothing.
  • Part 2

• The long chains of simple and easy reasonings by means of which geometers are accustomed to reach the conclusions of their most difficult demonstrations, had led me to imagine that all things, to the knowledge of which man is competent, are mutually connected in the same way, and that there is nothing so far removed from us as to be beyond our reach, or so hidden that we cannot discover it, provided only we abstain from accepting the false for the true, and always preserve in our thoughts the order necessary for the deduction of one truth from another.
  • Part 2

• Each problem that I solved became a rule, which served afterwards to solve other problems.
  • Part 2
  • Original: [...] et chaque vérité que je trouvois étant une règle qui me servoit après à en trouver d'autres, [...][2]
  • Variant: [...] and that thus each truth discovered was a rule available in the discovery of subsequent ones.[3]
  • Variant: [...] and every Truth which I found being a rule which afterwards served me to discover others;[4]

• On ne sauroit rien imaginer de si étranger et si peu croyable, qu’il n’ait été dit par quelqu’un des philosophes...
  • One cannot conceive anything so strange and so implausible that it has not already been said by one philosopher or another.
  • Variant: There is nothing so strange and so unbelievable that it has not been said by one philosopher or another.
  • Part 2
  • Cf. Cicero's "Nihil tam absurde dici potest, quod non dicatur ab aliquo philosophorum [There is nothing so absurd that it has not been said by some philosopher]" (De Divinatione, Book II, chapter LVIII, sec. 119).

• If we consider all external goods as equally beyond our power, we shall no more regret the absence of such goods... when deprived of them without any fault of ours, than our not possessing the kingdoms of China or Mexico; and thus making... a virtue of necessity, we shall no more desire health in disease, or freedom in imprisonment, than we now do bodies incorruptible as diamonds, or the wings of birds to fly with. But I confess there is need of prolonged discipline and frequently repeated meditation to accustom the mind to view all objects in this light; and I believe that in this chiefly consisted the secret of the power of such philosophers as in former times were enabled to rise superior to the influence of fortune, and, amid suffering and poverty, enjoy a happiness which their gods might have envied. For, occupied incessantly with the consideration of the limits prescribed to their power by nature, they became so entirely convinced that nothing was at their disposal except their own thoughts, that this conviction was of itself sufficient to prevent their entertaining any desire of other objects; and over their thoughts they acquired a sway so absolute, that they had some ground on this account for esteeming themselves more rich and more powerful, more free and more happy, than other men who, whatever be the favors heaped on them by nature and fortune, if destitute of this philosophy, can never command the realization of all their desires.
  • Part 3

• Je pense, donc je suis.
  • I think, therefore I am.
  • Part 4

• [B]ut if there were machines bearing the image of our bodies, and capable of imitating our actions as far as it is morally possible, there would still remain two most certain tests whereby to know that they were not therefore really men.
  • Part 5

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Discourse on the Method