from the
Discourse on Method
René Descartes

René Descartes

These pages: Discourse on Method

first page (here)

second page


Laurence J. Lafleur



index pages:

Discourse on the Method of Rightly Conducting the Reason and Seeking Truth in the Field of Science

translated by Laurence J. Lafleur

Copyright © 1960, The Liberal Arts Press, Inc.

Note (Hal’s):
This translation (at least the edition I have) omits the accompanying essays on Optics, Meteorology, and Geometry.

Headings are shown in brackets because they are added by the translator. As he has provided a combined text, with sources indicated, each quote also has its source noted:

  • [F] – French text of 1637;
  • [L] – Latin text of 1644 (translated by Etienne De Courcelles, revised by Descartes);
  • [b] – both (i.e., the translations of the quoted passage do not differ).

— end note

[ Part One
Some Thoughts on the Sciences]


Good sense is mankind’s most equitably divided endowment, for everyone thinks that he is so abundantly provided with it that even those most difficult to please in other ways do not usually want more than they have of this. As it is not likely that everyone is mistaken, this evidence shows that the ability to judge correctly, and to distinguish the true from the false—which is really what is meant by good sense or reason—is the same by nature in all men; and that differences of opinion are not due to differences in intelligence, but merely to the fact that we use different approaches and consider different things. For it is not enough to have a good mind: one must use it well. The greatest souls are capable of the greatest vices as well as of the greatest virtues; and those who walk slowly can, if they follow the right path, go much farther than those who run rapidly in the wrong direction.




So it is not my intention to present a method which everyone ought to follow in order to think well, but only to show how I have made the attempt myself. Those who counsel others must consider themselves superior to those whom they counsel, and if they fall short in the least detail they are to blame.

[b] But as soon as I had finished the course of studies which usually admits one to the ranks of the learned, I changed my opinion completely. For I found myself saddled with so many doubts and errors that I seemed to have gained nothing in trying to educate myself unless it was to discover more and more fully how ignorant I was.




I will say nothing of philosophy except that it has been studied for many centuries by the most outstanding minds without having produced anything which is not in dispute and consequently doubtful. I did not have enough presumption to hope to succeed better than the others; and when I noticed how many different opinions learned men may hold on the same subject, despite the fact that no more than one of them can ever be right, I resolved to consider almost as false any opinion which was merely plausible.




It is true that while I did nothing but observe the customs of other men, I found nothing there to satisfy me, and I noted just about as much difference of opinion as I had previously remarked among philosophers. The greatest profit to me was, therefore, that I became acquainted with customs generally approved and accepted by other great peoples that would appear extravagant and ridiculous among ourselves, and so I learned not to believe too firmly what I learned only from example and custom. Also I gradually freed myself from many errors which could make us less capable of correct reasoning. But after spending several years in thus studying the book of nature and acquiring experience, I eventually reached the decision to study my own self, and to employ all my abilities to try to choose the right path.



[ Part Two
The Principal Rules of the Method]


One of the first that occurred to me was that frequently there is less perfection in a work produced by several persons than in one produced by a single hand. Thus we notice that buildings conceived and completed by a single architect are usually more beautiful and better planned than those remodeled by several persons using ancient walls of various vintages along with new ones. Similarly, those ancient towns which were originally nothing but hamlets, and in the course of time have become great cities, are ordinarily very badly arranged compared to one of the symmetrical metropolitan districts which a city planner has laid out on an open plain according to his own designs.

[b] For public affairs are on a large scale, and large edifices are too difficult to set up again once they have been thrown down, too difficult even to preserve once they have been shaken, and their fall is necessarily catastrophic. It is certain that many institutions have defects, since their differences alone guarantee that much, but custom has no doubt inured us to many of them. Custom has perhaps even found ways to avoid or correct more defects than prudence could have done. Finally, present institutions are practically always more tolerable than would be a change in them; just as highways which twist and turn among the mountains become gradually so easy to travel, as a result of much use, that it is much better to follow them than to attempt to go more directly by climbing cliffs and descending to the bottom of precipices.

Compare to:

David Brooks on Edmund Burke


Even the decision to abandon all one’s preconceived notions is not an example for all to follow, and the world is largely composed of two sorts of individuals who should not try to follow it. First, there are those who think themselves more able than they really are, and so make precipitate judgments and do not have enough patience to think matters through thoroughly. From this it follows that once they have taken the liberty of doubting their established principles, thus leaving the highway, they will never be able to keep to the narrow path which must be followed to go more directly, and will remain lost all their lives. Secondly, there are those who have enough sense or modesty to realize that they are less able to distinguish the true from the false than are others, and so should rather be satisfied to follow the opinions of these others, and so should rather be satisfied to follow the opinions of these others than to search for better ones themselves.

As for myself, I should no doubt have belonged in the last class if I had had but a single teacher or if I had not known the differences which have always existed among the most learned. I had discovered in college that one cannot imagine anything so strange and unbelievable but that it has been upheld by some philosopher; and in my travels I had found that those who held opinions contrary to ours were neither barbarians nor savages, but that many of them were at least as reasonable as ourselves. [...] Faced with this divergence of opinion, I could not accept the testimony of the majority, for I thought it worthless as a proof of anything somewhat difficult to discover, since it is much more likely that a single man will have discovered it than a whole people. Nor, on the other hand, could I select anyone whose opinions seemed to me to be preferable to those of others, and I was thus constrained to embark on the investigation for myself.

[F] [...] as far as logic was concerned, its syllogisms and most of its other methods serve rather to explain to another what one already knows, or even, as in the art of Lully, to speak without judgment of what one does not know, than to learn new things.




The first rule was never to accept anything as true unless I recognized it to be evidently such: that is, carefully to avoid precipitation and prejudgment, and to include nothing in my conclusions unless it presented itself so clearly and distinctly to my mind that there was no occasion to doubt it.

The second was to divide each of the difficulties which I encountered into as many parts as possible, and as might be required for an easier solution.

The third was to think in an orderly fashion, beginning with the things which were simplest and easiest to understand, and gradually and by degrees reaching toward more complex knowledge, even treating, as though ordered, materials which were not necessarily so.

The last was always to make enumerations so complete, and reviews so general, that I would be certain that nothing was omitted.

[ Part Three
Some Moral Rules Derived from the Method]


The first was to obey the laws and customs of my country, constantly retaining the religion in which, by God’s grace, I had been brought up since childhood, and in all other matters to follow the most moderate and least excessive opinions to be found in the practices of the more judicious part of the community in which I would live. For I was then about to discard my own opinions in order to re-examine them, and meanwhile could do no better than to follow those of the most reliable judges. [...] Furthermore, it seemed to me that to learn people’s true opinions, I should pay attention to their conduct rather than to their words, not only because in our corrupt times there are few who are ready to say all that they believe, but also because many are not aware of their own beliefs, since the mental process of knowing a thing is distinct from, and can occur without, the mental process of knowing that we know it. [...] In particular, I considered as excessive all the promises by which we abandon some of our freedom.


My second maxim was to be as firm and determined in my actions as I could be, and not to act on the most doubtful decisions, once I had made them, any less resolutely than on the most certain. In this matter I patterned my behavior on that of travelers, who, finding themselves lost in a forest, must not wander about [...] but should go as straight as they can in the direction they first select and not change the direction except for the strongest reasons.


My third maxim was always to seek to conquer myself rather than fortune, to change my desires rather than the established order, and generally to believe that nothing except our thoughts is wholly under our control, so that after we have done our best in external matters, what remains to be done is absolutely impossible, at least as far as we are concerned. This maxim in itself shoud suffice to prevent me from desiring in the future anything which I could not acquire, and thus to make me happy.

[F] Besides, since our will neither seeks nor avoids anything except as it is judged good or bad by our reason, good judgment is sufficient to guarantee good behavior. Judging as best one can therefore implies that one acts as well as one can, or in other words, that one will acquire all the virtues and with them all other possible goods. Once we are sure of this, we cannot well fail to be happy.

[ Part Four
Proofs of the Existence of God and of the Human Soul]

[F] I had noticed for a long time that in practice it is sometimes necessary to follow opinions which we know to be very uncertain, just as though they were indubitable, as I stated before; but inasmuch as I desired to devote myself wholly to the search for truth, I thought that I should take a course precisely contrary, and reject as absolutely false anything of which I could have the least doubt, in order to see whether anything would be left after this procedure which could be called wholly certain. Thus, as our senses deceive us at times, I was ready to suppose that nothing was at all the way our senses represented them to be. As there are men who make mistakes in reasoning even on the simplest topics in geometry, I judged that I was as liable to error as any other, and rejected as false all the reasoning which I had previously accepted as valid demonstration. Finally, as the same percepts which we have when awake may come to us when asleep without their being true, I decided to suppose that nothing that had ever entered my mind was more real than the illusion of my dreams. But I soon noticed that while I then wished to think everything false, it was necessarily true that I who thought so was something. Since this truth, I think, therefore I am, was so firm and assured that all the most extravagant suppositions of the sceptics were unable to shake it, I judged that I could safely accept it as the first principle of the philosophy I was seeking.

text checked (see note) Oct 2006

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