# A Discourse of a Method for the Well Guiding of Reason and the Discovery of Truth in the Sciences

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# René Descartes. A Discourse of a Method for the Well Guiding of Reason / and the Discovery of Truth in the Sciences

## To the Understanding READER

The Great DESCARTES (who may justly challenge the first place amongst the Philosophers of this Age) is the Author of this Discourse; which in the Originall was so well known, That it could be no mans but his own, that his Name was not affix’d to it: I need say no more either of Him or It; He is best made known by Himself, and his Writings want nothing but thy reading to commend them. But as those who cannot compasse the Originals of Titian and Van-Dyke, are glad to adorne their Cabinets with the Copies of them; So be pleased favourably to receive his Picture from my hand, copied after his own Designe: You may therein observe the lines of a well form’d Minde, The hightnings of Truth, The sweetnings and shadowings of Probabilities, The falls and depths of Falshood; all which serve to perfect this Masterpiece. Now although my after-draught be rude and unpolished, and that perhaps I have touch’d it too boldly, The thoughts of so clear a Minde, being so extremely fine, That as the choisest words are too grosse, and fall short fully to expresse such sublime Notions; So it cannot be, but being transvested, it must necessarily lose very much of its native Lustre: Nay, although I am conscious (notwithstanding the care I have taken neither to wrong the Authours Sense, nor offend the Readers Ear) of many escapes which I have made; yet I so little doubt of being excused, That I am confident, my endeavour cannot but be gratefull to all Lovers of Learning; for whose benefit I have Englished, and to whom I addresse this Essay, which contains a Method, by the Rules whereof we may Shape our better part, Rectifie our Reason, Form our Manners and Square our Actions, Adorn our Mindes, and making a diligent Enquiry into Nature, wee may attain to the Knowledge of the Truth, which is the most desirable union in the World.

Our Authour also invites all letterd men to his assistance in the prosecution of this Search; That for the good of Mankinde, They would practise and communicate Experiments, for the use of all those who labour for the perfection of arts and sciences: every man now being obliged to the furtherance of so beneficiall an undertaking, I could not but lend my hand to open the curtain, and discover this new model of philosophy; which I now publish, neither to humour the present, nor disgust former times; but rather that it may serve for an innocent divertisement to those, who would rather reform themselves, then the rest of the world; and who, having the same seeds and grounds, and knowing that there is nothing new under the sun; that novelty is but oblivion, and that knowledge is but remembrance, will study to finde out in themselves, and restore to posterity those lost arts, which render antiquity so venerable; and strive (if it be possible) to go beyond them in other things, as well as time: who minde not those things which are above, beyond, or without them; but would rather limit their desires by their power, then change the course of nature; who seek the knowledge, and labour for the conquest of themselves; who have vertue enough to make their own fortune; and who prefer the culture of the minde before the adorning of the body; to such as these I present this discourse (whose pardon I beg, for having so long detain’d them from so desirable a conversation;) and conclude with this advice of the divine plato:

Cogita in te, præter Animum, nihil esse mirabile.

A DISCOURSE OF A METHOD, For the wel-guiding of Reason; AND The discovery of Truth in the SCIENCES

If this Discourse seem too long to be read at once, it may be divided into six parts. In the first, are divers Considerations touching the Sciences. In the second, the principall Rules of that Method which the Author hath studyed. In the third, some of those in morality, which he hath drawn from this Method. In the fourth, the reasons whereby the existence of God and of the humane Soul is proved; which are the grounds of his Metaphysicks. In the fift, the order of these Physicall questions, which he hath examined, and particularly the explication of the hearts motion; with some other difficulties relating to Physick; as also the difference between our Souls and those of beasts. In the last, what he conceives requisit to make a further inquiry into Nature, then hath hitherto been made. And what reasons induc’d him to write.

## PART. I

Right understanding is the most equally divided thing in the World; for every one beleevs himself so well stor’d with it, that even those who in all other things are the hardest to be pleas’d, seldom desire more of it then they have; wherein it is not likely that all Men are deceived: But it rather witnesseth, That the faculty of right-judging and distinguishing truth from falshood (which is properly call’d, Understanding or Reason) is naturally equal in all Men. And as the diversity of our Opinions, is not, because some are more reasonable then others; but only that we direct our thoughts several ways, neither do we consider the same things. For ’tis not enough to have good faculties, but the principal is, to apply them well. The greatest Souls are as capable of the greatest Vices, as of the most eminent Vertues: And those who move but very slowly, may advance much farther, if they always follow the right way; then those who run and straggle from it.

For my part, I never presum’d that my Minde was more perfect in any thing then an ordinary Mans; nay, I have often wish’d to have had my thoughts as quick, my imagination as clear and distinct, and my memory as large and as ready as some other Men have had. And I know no Qualities which serve more then those to the perfection of the Minde; for as for Reason or Understanding, forasmuch as it is the only thing which makes us Men, and distinguisheth us from beasts, I will beleeve it to be entire in every One, and follow herein the common opinion of the Philosophers, who say, That there is only more or less among the Accidents, and not amongst the Forms or nature of the Individuals of one species.

But I shall not stick to say, That I beleeve my self very happy, in having encountred from my youth with certain ways which have led me to considerations and Maximes, from which I have found a Method; whereby methinks, I have the means by degrees to augment my knowledg, and by little and little to raise it up to the highest pitch, whereto the meaness of my capacity, & the short course of my life can permit it to attain. For I have already reaped such fruits from it, that although in the judgment I make of my self, I endevour always rather to incline to mistrust, then to presumption. And looking on the divers actions and undertakings of all Men, with the eye of a Philosopher, there is almost none which to me seems not vain and useless. Yet I am extremely satisfied with the Progress, which (as it seems to me) I have already made in the search of Truth, and do conceive such hopes for the future, That if among the employments of Men, purely Men, there is any solidly good, and of importance, I dare beleeve it is that which I have chosen: Yet it may be that I deceive my self, and perhaps it is but a little Copper and Glass which I take for Gold and Diamonds. I know how subject we are to mistake in those things which concern us, and how jealous we ought to be of the judgment of our friends, when it is in our favor. But I should willingly in this Discourse, trace out unto you the ways which I have followed, and represent therein my life, as in a Picture, to the end, that every one may judge thereof; and that learning from common Fame, what mens opinions are of it, I may finde a new means of instructing my self; which I shall add to those which I customarily make use of.

Neither is it my design to teach a Method which every Man ought to follow, for the good conduct of his reason; but only to shew after what manner I have endevoured to order mine own. Those who undertake to give precepts, ought to esteem themselves more able, then those to whom they give them, and are blame-worthy, if they fail in the least. But proposing this but as a History, or if you will have it so, but as a Fable; wherein amongst other examples, which may be imitated, we may perhaps find divers others which we may have reason to decline: I hope it will be profitable to some, without being hurtfull to any; and that the liberty I take will be gratefull to all.

I have been bred up to Letters from mine infancy; & because I was perswaded, that by their means a man might acquire a clear and certain knowledg of all that’s usefull for this life, I was extremely desirous to learn them: But as soon as I had finish’d all the course of my Studies, at the end whereof Men are usually receiv’d amongst the rank of the learned. I wholly changed my opinion, for I found my self intangled in so many doubts and errors, that me thought I had made no other profit in seeking to instruct my self, but that I had the more discovered mine own ignorance. Yet I was in one of the most famous Schools in Europe; where I thought, if there were any on earth, there ought to have been learned Men. I had learnt all what others had learnt; even unsatisfied with the Sciences which were taught us, I had read over all Books (which I could possibly procure) treating of such as are held to be the rarest and the most curious. Withall, I knew the judgment others made of me; and I perceiv’d that I was no less esteem’d then my fellow Students, although there were some amongst them that were destin’d to fill our Masters rooms. And in fine, our age seem’d to me as flourishing and as fertile of good Wits, as any of the preceding, which made me take the liberty to judg of all other men by my self, and to think, That there was no such learning in the world, as formerly I had been made beleeve.

Yet did I continue the esteem I had of those exercises which are the employments of the Schools: I knew that Languages which are there learnt, are necessary for the understanding of ancient Writers, That the quaintness of Fables awakens the Minde; That the memorable actions in History raise it up, and that being read with discretion, they help to form the judgment. That the reading of good books, is like the conversation with the honestest persons of the past age, who were the Authors of them, and even a studyed conversation, wherein they discover to us the best only of their thoughts. That eloquence hath forces & beauties which are incomparable. That Poetry hath delicacies and sweets extremly ravishing; That the Mathematicks hath most subtile inventions, which very much conduce aswel to content the curious, as to facilitate all arts, and to lessen the labour of Men: That those writings which treat of manners contain divers instructions, and exhortations to vertue, which are very usefull. That Theology teacheth the way to heaven; That Philosophy affords us the means to speake of all things with probability, and makes her self admir’d, by the least knowing Men. That Law, Physick and other sciences bring honor and riches to those who practice them; Finally that its good to have examin’d them all even the falsest and the most superstitious, that we may discover their just value, and preserve our selves from their cheats.

But I thought I had spent time enough in the languages, and even also in the lecture of ancient books, their histories and their fables. For ’tis even the same thing to converse with those of former ages, as to travel. Its good to know something of the manners of severall Nations, that we may not think that all things against our Mode are ridiculous or unreasonable, as those are wont to do, who have seen Nothing. But when we employ too long time in travell, we at last become strangers to our own Country, and when we are too curious of those things, which we practised in former times, we commonly remain ignorant of those which are now in use. Besides, Fables make us imagine divers events possible, which are not so: And that even the most faithfull Histories, if they neither change or augment the value of things, to render them the more worthy to be read, at least, they always omit the basest and less remarkable circumstances; whence it is, that the rest seems not as it is; and that those who form their Manners by the examples they thence derive, are subject to fall into the extravagancies of the Paladins of our Romances, and to conceive designes beyond their abilities.

I highly priz’d Eloquence, and was in love with Poetry; but I esteem’d both the one and the other, rather gifts of the Minde, then the fruits of study. Those who have the strongest reasoning faculties, and who best digest their thoughts, to render them the more clear and intelligible, may always the better perswade what they propose, although they should speak but a corrupt dialect, and had never learnt Rhetorick: And those whose inventions are most pleasing, and can express them with most ornament and sweetness, will still be the best Poets; although ignorant of the Art of Poetry.

Beyond all, I was most pleas’d with the Mathematicks, for the certainty and evidence of the reasons thereof; but I did not yet observe their true use, and thinking that it served only for Mechanick Arts; I wondred, that since the grounds thereof were so firm and solid, that nothing more sublime had been built thereon. As on the contrary, I compar’d the writings of the Ancient heathen which treated of Manner, to most proud and stately Palaces which were built only on sand and mire, they raise the vertues very high, and make them appear estimable above all the things in the world; but they doe not sufficiently instruct us in the knowledg of them, and often what they call by that fair Name, is but a stupidness, or an act of pride, or of despair, or a paricide.

I reverenc’d our Theology, and pretended to heaven as much as any; But having learnt as a most certain Truth, that the way to it, is no less open to the most ignorant, then to the most learned; and that those revealed truths which led thither, were beyond our understanding, I durst not submit to the weakness of my ratiocination. And I thought, that to undertake to examine them, and to succeed in it, requir’d some extraordinary assistance from heaven, and somewhat more then Man. I shall say nothing of Philosophy, but that seeing it hath been cultivated by the most excellent wits, which have liv’d these many ages, and that yet there is nothing which is undisputed, and by consequence, which is not doubtfull. I could not presume so far, as to hope to succeed better then others. And considering how many different opinions there may be on the same thing, maintain’d by learned Men, and yet that there never can be but one only Truth, I reputed almost all false, which had no more then probability in it.

As for other Sciences, since they borrow their Principles from Philosophy, I judg’d that nothing which was solid could be built upon such unsound foundations; and neither honour nor wealth were sufficient to invite me to the study of them. For (I thank God) I found not my self in a condition which obliged me to make a Trade of Letters for the relief of my fortune. And although I made it not my profession to despise glory with the Cynick; yet did I little value that which I could not acquire but by false pretences. And lastly, for unwarrantable Studies, I thought I already too well understood what they were, to be any more subject to be deceived, either by the promises of an Alchymist, or by the predictions of an Astrologer, or by the impostures of a Magician, or by the artifice or brags of those who profess to know more then they do.

By reason whereof, as soon as my years freed me from the subjection of my Tutors, I wholly gave over the study of Letters, and resolving to seek no other knowledge but what I could finde in my self, or in the great book of the World, I imployed the rest of my youth in Travell, to see Courts and Armies, to frequent people of severall humors and conditions, to gain experience, to hazard my self in those encounters of fortune which should occurr; and every-where to make such a reflection on those things which presented themselves to me, that I might draw profit from them. For (me thought) I could meet with far more truth in the discourses which every man makes touching those affairs which concern him, whose event would quickly condemn him, if he had judg’d amisse; then amongst those which letter’d Men make in their closets touching speculations, which produce no effect, and are of no consequence to them, but that perhaps they may gain so much the more vanity, as they are farther different from the common understanding: Forasmuch as he must have imployed the more wit and subtilty in endeavouring to render them probable. And I had always an extreme desire to learn to distinguish Truth from Falshood, that I might see cleerly into my actions, and passe this life with assurance.

Its true, that whiles I did but consider the Manners of other men, I found little or nothing wherein I might confirm my self: And I observ’d in them even as much diversity as I had found before in the opinions of the Philosophers: So that the greatest profit I could reap from them was, that seeing divers things, which although they seem to us very extravagant and ridiculous, are nevertheless commonly received and approved by other great Nations, I learn’d to beleeve nothing too firmly, of what had been onely perswaded me by example or by custom, and so by little and little I freed my self from many errors, which might eclipse our naturall light, and render us lesse able to comprehend reason. But after I had imployed some years in thus studying the Book of the World, and endeavouring to get experience, I took one day a resolution to study also within my self, and to employ all the forces of my minde in the choice of the way I was to follow: which (me thought) succeeded much better, then if I had never estranged my self from my Country, or from my Books.

## PART. II

I was then in Germany, whither the occasion of the Wars (which are not yet finished) call’d me; and as I return’d from the Emperors Coronation towards the Army, the beginning of Winter stopt me in a place, where finding no conversation to divert me and on the other sides having by good fortune no cares nor passions which troubled me, I stayd alone the whole day, shut up in my Stove, where I had leasure enough to entertain my self with my thoughts. Among which one of the first was that I betook my self to consider, That oft times there is not so much perfection in works compos’d of divers peeces, and made by the hands of severall masters, as in those that were wrought by one only: So we may observe that those buildings which were undertaken and finished by one onely, are commonly fairer and better ordered then those which divers have laboured to patch up, making use of old wals, which were built for other purposes; So those ancient Cities which of boroughs, became in a succession of time great Towns, are commonly so ill girt in comparison of other regular Places, which were design’d on a flatt according to the fancy of an Engeneer; and although considering their buildings severally, we often find as much or more art, then in those of other places; Yet to see how they are rank’d here a great one, there a little one, and how they make the streets crooked and uneven, One would say, That it was rather Fortune, then the will of Men indued with reason, that had so disposed them. And if we consider, that there hath always been certain Officers, whose charge it was, to take care of private buildings, to make them serve for the publique ornament; We may well perceive, that it’s very difficult, working on the works of others, to make things compleat. So also did I imagine, that those people who formerly had been half wilde, and civiliz’d but by degrees, made their laws but according to the incommodities which their crimes and their quarrels constrain’d them to, could not be so wel pollic’d, as those who from the beginning of their association, observ’d the constitutions of some prudent Legislator. As it is very certain, that the state of the true Religion, whose Ordinances God alone hath made, must be incomparably better regulated then all others. And to speak of humane things, I beleeve that if Sparta hath formerly been most flourishing, it was not by reason of the goodness of every of their laws in particular, many of them being very strange, and even contrary to good manners, but because they were invented by one only, They all tended to One End. And so I thought the sciences in Books, at least those whose reasons are but probable, and which have no demonstrations, having been compos’d of, and by little and little enlarg’d with, the opinions of divers persons, come not so near the Truth, as those simple reasonings which an understanding Man can naturally make, touching those things which occurr. And I thought besides also, That since we have all been children, before we were Men; and that we must have been a long time govern’d by our appetites, and by our Tutors, who were often contrary to one another, and neither of which alwayes counsel’d us for the best; It’s almost impossible that our judgment could be so clear or so solid, as it might have been, had we had the intire use of our reason from the time of our birth, and been always guided by it alone.

Its true, we doe not see the houses of a whole Town pull’d down purposely to re build them of another fashion; and to make the streets the fairer; But we often see, that divers pull their own down to set them up again, and that even sometimes they are forc’d thereunto, when they are in danger to fall of themselves, and that their foundations are not sure. By which example I perswaded my self, that there was no sense for a particular person, to design the Reformation of a State, changing all from the very foundations, and subverting all to redress it again: Nor even also to reform the bodies of Sciences, or the Orders already established in the Schools for teaching them. But as for all the Opinions which I had till then receiv’d into my beleef, I could not doe better then to undertake to expunge them once for all, that afterwards I might place in their stead, either others which were better, or the same again, as soon as I should have adjusted them to the rule of reason. And I did confidently beleeve, that by that means I should succeed much better in the conduct of my life, then if I built but on old foundations, and only relyed on those principles, which I suffer’d my self to be perswaded to in my youth, without ever examining the Truth of them. For although I observ’d herein divers difficulties, yet were they not without cure, nor comparable to those which occurr in the reformation of the least things belonging to the publick: these great bodies are too unweldy to be rais’d; being cast down, or to be held up when they are shaken, neither can their falls be but the heavyest.

As for their imperfections, if they have any, as the only diversity which is amongst them, is sufficient to assure us that many have. Custome hath (without doubt) much sweetned them, and even it hath made others wave, or insensibly correct a many, whereto we could not so well by prudence have given a remedy. And in fine, They are alwayes more supportable, then their change can be, Even, as the great Roads, which winding by little and little betwixt mountains, become so plain and commodious, with being often frequented, that it’s much better to follow them, then to undertake to goe in a strait line by climbing over the rocks, and descending to the bottom of precipices. Wherefore I can by no means approve of those turbulent and unquiet humors, who being neither call’d by birth or fortune to the managing of publique affairs, yet are alwayes forming in Idea, some new Reformation. And did I think there were the least thing in this Discourse, which might render me suspected of that folly, I should be extremely sorry to suffer it to be published; I never had any designe which intended farther then to reform my own thoughts and to build on a foundation which was wholly mine. But though I present you here with a Modell of my work, because it hath sufficiently pleased me; I would not therefore counsell any one to imitate it. Those whom God hath better endued with his graces, may perhaps have more elevated designes; but I fear me, lest already this be too bold for some. The resolution only of quitting all those opinions which we have formerly receiv’d into our belief, is not an example to be followed by every One; and the world is almost compos’d but of two sorts of Men, to whom it’s no wayes convenient, to wit, of those, who beleeving themselves more able then they are, cannot with-hold themselves from precipitating their judgments, nor have patience enough to steer all their thoughts in an orderly course. Whence it happens, that if they should once take the liberty to doubt of those principles which they have already received, and to stray from the common road, they could never keep the path which leads strait forwards, and so, would straggle all their lives. And of such who having reason and modesty enough to judg that they are less able to distinguish truth from falshood then others, from whom they may receive instruction, ought much rather to be content to follow other Mens opinions, rather then to seek after better themselves.

And for my part, I had undoubtedly been of the number of those latter, had I never had but one Master, or had I not known the disputes which have alwayes hapned amongst the most learned. For having learnt from the very School, That one can imagin nothing so strange or incredible, which had not been said by some one of the Philosophers; And having since observ’d in my travails, That all those whose opinions are contrary to ours, are not therefore barbarous or savage, but that many use as much or more reason then we; and having consider’d how much one Man with his own understanding, bred up from his childhood among the French or the Dutch, becomes different from what he would be, had he alwayes liv’d amongst the Chineses, or the Cannibals: And how even in the fashion of our Clothes, the same thing which pleas’d ten years since, and which perhaps wil please ten years hence, seems now to us ridiculous and extravagant. So that it’s much more Custome and Example which perswades us, then any assured knowledg; and notwithstanding that plurality of voices is a proof of no validity, in those truths which are hard to be discovered; for that it’s much more likely for one man alone to have met with them, then a whole Nation; I could choose no Man whose opinion was to be preferr’d before anothers: And I found my self even constrain’d to undertake the conduct of my self.

But as a man that walks alone, and in the dark, I resolv’d to goe so softly, and use so much circumspection in all things, that though I advanc’d little, I would yet save my self from falling. Neither would I begin quite to reject, some opinions, which formerly had crept into my belief, without the consent of my reason, before I had employed time enough to form the project of the work I undertook, and to seek the true Method to bring me to the knowledg of all those things, of which my understanding was capable.

I had a little studyed, being young, of the parts of Philosophy, Logick, and of the Mathematicks, the Analysis of the Geometricians, and Algebra: Three arts or sciences which seem’d to contribute somewhat conducing to my designe: But examining them, I observ’d, That as for Logick, its Sylogisms, and the greatest part of its other Rules, serve rather to expound to another the things they know, or even as Lullies art, to speak with judgment of the things we are ignorant of, then to learn them. And although in effect it contain divers most true and good precepts, yet there are so many others mixed amongst them, either hurtfull or superfluous, That it’s even as difficult to extract them, as ’tis to draw a Diana or a Mercury out of a lump of Marble, which is not yet rough-hewn; as for the Analysis of the Ancients, and the Algebra of the Moderns; besides that, they extend only to matters very abstract, and which seem to be of no use; The first being alwayes so tyed to the consideration of figures, That it cannot exercise the understanding, without very much tiring the imagination. And in the latter they have so subjected themselves to certain Rules and cyphers, that they have made a confus’d and obscure art which perplexeth the minde, in stead of a Science to instruct it. For this reason, I thought I ought to seek some other Method, which comprehending the advantages of these, they might be exempt from their defects. And as the multitude of Laws often furnisheth excuses for vice; so a State is fair better polic’d, when having but a few, they are very strictly observ’d therein: So, instead of the great many precepts whereof Logick is compos’d, I thought these four following would be sufficient for me, if I took but a firm and constant resolution not once to fail in the observation of them.