If this Discourse appears too long to be read all at once, it may

be separated into six portions. And in the first there will be found various

considerations respecting the sciences; in the second the principal rules

regarding the Method which the author has sought out; while in the third

are some of the rules of morality which he has derived from this Method.

In the fourth are the reasons by which he proves the existence of God and

of the human soul which form the foundation of his Metaphysic. In the fifth,

the order of the questions regarding physics which he has investigated,

and particularly the explanation of the movement of the heart, and of some

other difficulties which pertain to medicine as also the difference between

the soul of man and that of the brutes. And in the last part the questions

raised relate to those matters which the author believes to be requisite

in order to advance further in the investigation of nature, in addition

to the reasons that caused him to write.






PART I.



Good sense is of all things in the world the most equally distributed,

for everybody thinks himself so abundantly provided with it, that even

those most difficult to please in all other matters do not commonly desire

more of it than they already possess. It is unlikely that this is an error

on their part; it seems rather to be evidence in support of the view that

the power of forming a good judgment and of distinguishing the true from

the false, which is properly speaking what is called Good sense or Reason,

is by nature equal in all men. Hence too it will show that the diversity

of our opinions does not proceed from some men being more rational than

others, but solely from the fact that our thoughts pass through diverse

channels and the same objects are not considered by all. For to be possessed

of good mental powers is not sufficient; the principal matter is to apply

them well. The greatest minds are capable of the greatest vices as well

as of the greatest virtues and those who proceed very slowly may, provided

they always follow the straight road, really advance much faster than those

who, though they run, forsake it. 



For myself I have never ventured to presume that my mind was in any

way more perfect than that of the ordinary man; I have even longed to possess

thought as quick;, or an imagination as accurate and distinct, or a memory

as comprehensive or ready, as some others. And besides these I do not know

any other qualities that make for the perfection of the human mind. For

as to reason or sense, inasmuch as it is the only thing that constitutes

us men and distinguishes us from the brutes, I would fain believe that

it is to be found complete in each individual, and in this I follow the

common opinion of the philosophers, Who say that the question of more or

less occurs only in the sphere of the accidents and does not affect

the forms or natures of the individuals in the same species.





But I shall not hesitate to say that I have had great good fortune from

my youth up, in lighting upon and pursuing certain paths which have conducted

me to considerations and maxims from which I have formed a Method, by whose

assistance it appears to me I have the means of gradually increasing my

knowledge and of little by little raising it to the highest possible point

which the mediocrity of my talents and the brief duration of my life can

permit me to reach. For I have already reaped from it fruits of such a

nature that, even though I always try in the judgments I make on myself

to lean to the side of selfdepreciation rather than to that of arrogance,

and though, looking with the eye of a philosopher on the diverse actions

and enterprises of all mankind, I find scarcely any which do not seem to

me vain and useless, I do not cease to receive extreme satisfaction in

the progress which I seem to have already made in the search after truth,

and to form such hopes for the future as to venture to believe that, if

amongst the occupations of men, simply as men, that is the one in particular

that is excellent and important, that is the one which I have selected.





It must always be recollected, however, that possibly I deceive myself,

and that what I take to be gold and diamonds is perhaps no more than copper

and glass. I know how subject we are to delusion in whatever touches ourselves,

and also how much the judgments of our friends ought to be suspected when

they are in our favour. But in this Discourse I shall be very happy to

show the Paths I have followed, and to set forth my life as in a picture,

so that everyone may judge of it for himself; and thus in learning from

the common talk what are the opinions which are held of it, a new means

of obtaining self-instruction will be reached, which I shall add to those

which I have been in the habit of using. 



Thus my design is not here to teach the Method which everyone should

follow in order to promote the good conduct of his Reason, but only to

show in what manner I have endeavoured to conduct my own. Those who set

about giving precepts must esteem themselves more skilful than those to

whom they advance them, and if they fall short in the smallest matter they

must of course take the blame for it. But regarding this Treatise simply

as a history, or, if you prefer it, a fable in which, amongst certain things

which may be imitated, there are possibly others also which it would not

be right to follow, I hope that it will be of use to some without being

hurtful to any, and that all will thank me for my frankness. 



I have been nourished on letters since my childhood, and since I was

given to believe that by their means a clear and certain knowledge could

be obtained of all that is useful in life, I had an extreme desire to acquire

instruction. But so soon as I had achieved the entire course of study at

the loss of which one is usually received into the ranks of the learned,

I entirely changed my opinion. For I found myself embarrassed with so many

doubts and errors that it seemed to me that the effort to instruct myself

had no effect other than the increasing discovery of my own ignorance.

And yet I was studying at one of the most celebrated Schools in Europe,

where I thought that there must be men of learning if they were to be found

anywhere in the world. I learned there all that others learned; and not

being satisfied with the sciences that we were taught, I even read through

all the books which fell into my hands, treating of what is considered

most curious and rare. Along with this I knew the judgments that others

had formed of me, and I did not feel that I was esteemed inferior to my

fellow-students, although there were amongst them some destined to fill

the places of our masters. And finally our century seemed to me as flourishing,

and as fertile in great minds, as any which had preceded. And this made

me take the liberty of judging all others by myself and of coming to the

conclusion that there was no learning in the world such as I was formerly

led to believe it to be. 



I did not omit, however, always to hold in esteem those exercises which

are the occupation of the Schools. I knew that the Languages which one

learns there are essential for the understanding of all ancient literature;

that fables with their charm stimulate the mind and histories of memorable

deeds exalt it; and that, when read with discretion, these books assist

in forming a sound judgment I was aware that the reading of all good books

is indeed like a conversation with the noblest men of past centuries who

were the authors of them, nay a carefully studied conversation, in which

they reveal to us none but the best of their thoughts. I deemed Eloquence

to have a power and beauty beyond compare; that Poesy has most ravishing

delicacy and sweetness; that in Mathematics there are the subtlest discoveries

and inventions which may accomplish much, both in satisfying the curious,

and in furthering all the arts, and in diminishing man's labour; that those

writings that deal with Morals contain much that is instructive, and many

exhortations to virtue which are most useful; that Theology points out

the way to heaven; that Philosophy teaches us to speak with an appearance

of truth on all things, and causes us to be admired by the less learned;

than Jurisprudence, Medicine and all other sciences bring honour and riches

to those who cultivate them; and finally that it is good to have examined

all things, even those most full of superstition and falsehood, in order

that we may know their just value, and avoid being deceived by them. 



But I considered that I had already given sufficient time to languages

and likewise even to the reading of the literature of the ancients, both

their histories and their fables. For to converse with those of other centuries

is almost the same thing as to travel. It is good to know something of

the customs of different peoples in order to judge more sanely of our own,

and not to think that everything of a fashion not ours is absurd and contrary

to reason, as who those who have seen nothing. But when one employs too

much time in travelling, one becomes a stranger in one's own country, and

when one is too curious about things which were practised in past centuries,

one is usually very ignorant about those which are practised in our own

time. Besides, fables make one imagine many events possible which in reality

are not so, and even the most accurate of histories, if they do not exactly

misrepresent or exaggerate the value of things in order to render them

more worthy of being read, at least omit in them all the circumstances

which are basest and least notable; and from this fact it follows that

what is retained is not portrayed as it really is and that those who regulate

their conduct by examples which they derive from such a source, are liable

to fall into the extravagances of the knights-errant of Romance, and form

projects beyond their power of performance. 



I esteemed Eloquence most highly and I was enamoured of Poesy, but I

thought that both were gifts of the mind rather than fruits of study. Those

who have the strongest power of reasoning, and who most skilfully arrange

their thoughts in order to tender them clear and intelligible, have the

best power of persuasion even if they can but speak the language of Lower

Brittany and have never learned Rhetoric. And those who have the most delightful

original ideas and who know how to express them with the maximum of style

and suavity, would not fail to be the best poets even if the art of Poetry

were unknown to them. 



Most of all was I delighted with Mathematics because of the certainty

of its demonstrations and the evidence of its reasoning; but I did not

yet understand its true use, and, believing that it was of service only

in the mechanical arts, I was astonished that, seeing how firm and solid

was its basis, no loftier edifice had been reared thereupon. On the other

hand I compared the works of the ancient pagans which deal with Morals

to palaces most superb and magnificent, which are yet built on sand and

mud alone. They praise the virtues most highly and show them to be more

worthy of being prized than anything else in the world, but they do not

sufficiently teach us to become acquainted with them, and often that which

is called by a fine name is nothing but insensibility, or pride, or despair,

or parricide. 



I honoured our theology and aspired as much as anyone to reach to heaven,

but having learned to regard it as a most highly assured fact that the

road is not less open to the most ignorant than to the most learned, and

that the revealed truths which conduct thither are quite above our intelligence,

I should not have dared to submit them to the feebleness of my reasonings;

and I thought that, in order to undertake to examine them and succeed in

so doing, it was necessary to have some extraordinary assistance from above

and to be more than a mere man. 



I shall not say anything about Philosophy, but that, seeing that it

has been cultivated for many centuries by the best minds that have ever

lived, and that nevertheless no single thing is to be found in it which

is not subject of dispute, and in consequence which is not dubious I had

not enough presumption to hope to fare better there than other men had

done. And also, considering how many conflicting opinions there may be

regarding the self-same matter, all supported by learned people, while

there can never be more than one which is true, I esteemed as well-nigh

false all that only went as far as being probable. 



Then as to the other sciences, inasmuch as they derive their principles

from Philosophy, I judged that one could have built nothing solid on foundations

so far from firm. And neither the honour nor the promised gain was sufficient

to persuade me to cultivate them, for, thanks be to God, I did not find

myself in a condition which obliged me to make a merchandise of science

for the improvement of my fortune; and, although I did not pretend to scorn

all glory like the Cynics, I yet had very small esteem for what I could

not hope to acquire, excepting through fictitious tittles. And, finally,

as to false doctrines, I thought that I already knew well enough what they

were worth to be subject to deception neither by the promises of an alchemist,

the predictions of an astrologer, the impostures of a magician, the artifices

or the empty boastings of any of those who make a profession of knowing

that of which they are ignorant. 



This is why, as soon as age permitted me to emerge from the control

of my tutors, I entirely quitted the study of letters. And resolving to

seek no other science than that which could be found in myself, or at least

in the great book of the world, I employed the rest of my youth in travel,

in seeing courts and armies, in intercourse with men of diverse temperaments

and conditions, in collecting varied experiences, in proving myself in

the various predicaments in which I was placed by fortune, and under all

circumstances bringing my mind to bear on the things which came before

it, so that I might derive some profit from my experience. For it seemed

to me that I might meet with much more truth in the reasonings that each

man makes on the matters that specially concern him, and the issue of which

would very soon punish him if he made a wrong judgment, than in the case

of those made by a man of letters in his study touching speculations which

lead to no results and which bring about no other consequences to himself

excepting that he will be all the more vain the more they are removed from

common sense, since in this case it proves him to have employed so much

the more ingenuity and skill in trying to make them seem probable. And

I always had an excessive desire to learn to distinguish the true from

the false, in order to see clearly in my actions and to walk with confidence

in this life. 



It is true that while I only considered the manners of other men I found

in them nothing to give me settled convictions; and I remarked in them

almost as much diversity as I had formerly seen in the opinions of philosophers.

So much was this the case that the greatest profit which I derived from

their study was that, in seeing many things which, although they seem to

us very extravagant and ridiculous, were yet commonly received and approved

by other great nations, I learned to believe nothing too certainly of which

I had only been convinced by example and custom. Thus, little by little

I was delivered from many errors which might have obscured our natural

vision and rendered us less capable of listening to Reason. But after I

had employed several years in thus studying the book of the world and trying

to acquire some experience, I one day formed the resolution of also making

myself an object of study and of employing all the strength of my mind

in choosing the road I should follow. This succeeded much better, it appeared

to me, than if I had never departed either from my country or my books.





PART II.



I was then in Germany, to which country I had been attracted by the

wars which are not yet at an end. And as I was returning from the coronation

of the Emperor to join the army, the setting in of winter detained me in

a quarter where, since I found no society to divert me, while fortunately

I had also no cares or passions to trouble me, I remained the whole day

shut up alone in a stove-heated room, where I had complete leisure to occupy

myself with my own thoughts. One of the first of the considerations that

occurred to me was that there is very often less perfection in works composed

of several portions, and carried out by the hands of various masters, than

in those on which one individual alone has worked. Thus we see that buildings

planned and carried out by one architect alone are usually more beautiful

and better proportioned than those which many have tried to put in order

and improve making use of old walls which were built with other ends in

view. In the same way also, those ancient cities which, originally mere

villages, have become in the process of time great towns, are usually badly

constructed in comparison with those which are regularly laid out on a

plain by a surveyor who is free to follow his own ideas. Even though, considering

their buildings each one apart, there is often as much or more display

of skill in the one case than in the other, the former have large buildings

and small buildings indiscriminately placed together, thus rendering the

streets crooked and irregular, so that it might be said that it was chance

rather than the skill of men guided by reason that led to such an arrangement.

And if we consider that this happens despite the fact that from all time

there have been certain officials who have had the special duty of looking

after the buildings of private individuals in order that they may be public

ornaments, we shall understand how difficult it is to bring about much

that is satisfactory in operating only upon the works of others. Thus I

imagined that those people who were once half-savage, and who have become

civilised only by slow degrees, merely forming their laws as the disagreeable

necessities of their crimes and quarrels constrained them, could not succeed

in establishing so good a system of government as those who, from the time

they first came together as communities, carried into effect the constitution

laid down by some prudent legislator. Thus it is quite certain that the

constitution of the true Religion whose ordinances are of God alone is

incomparably better regulated than any other. And, to come down to human

affairs, I believe that if Sparta was very flourishing in former times,

this was not because of the excellence of each and every one of its laws,

seeing that many were very strange and even contrary to good morals, but

because, being drawn up by one individual, they all tended towards the

same end. And similarly I thought that the sciences found in books - in

those at least whose reasonings are only probable and which have no demonstrations,

composed as they are of the gradually accumulated opinions of many different

individuals - do not approach so near to the truth as the simple reasoning

which a man of common sense can quite naturally carry out respecting the

things which come immediately before him. Again I thought that since we

have all been children before being men, and since it has for long fallen

to us to be governed by our appetites and by our teachers who often enough

contradicted one another, and none of whom perhaps counselled us always

for the best), it is almost impossible that our judgments should be so

excellent or solid as they should have been had we had complete use of

our reason since our birth, and had we been guided by its means alone.





It is true that we do not find that all the houses in a town are rased

to the ground for the sole reason that the town is to be rebuilt in another

fashion, with streets made more beautiful; but at the same time we see

that many people cause their own houses to be knocked down in order to

rebuild them, and that sometimes they are forced so to do where there is

danger of the houses falling of themselves, and when the foundations are

not secure. From such examples I argued to myself that there was no plausibility

in the claim of any private individual to reform a state by altering everything,

and by overturning it throughout, in order to set it right again. Nor is

it likewise probable that the whole body of the Sciences, or the order

of teaching established by the Schools, should be reformed. that as regards

all the opinions which up to this time I had embraced, I thought I could

not do better than endeavour once for all to sweep them completely away,

so that they might later on be replaced, either by others which were better,

or by the same, when I had made them conform to the uniformity of a rational

scheme And I firmly believed that by this means I should succeed in directing

my life much better than if I had only built on old foundations, and relied

on principles of which I allowed myself to be in youth persuaded without

having inquired into their truth. For although in so doing I recognised

various difficulties, these were at the same time not unsurmountable, nor

comparable to those which are found in reformation of the most insignificant

kind in matters which concern the public. In the case of great bodies it

is too difficult a task to raise them again when they are once thrown down,

or even to keep them in their places when once thoroughly shaken; and their

fall cannot be otherwise than very violent. Then as to any imperfections

that they may possess (and the very diversity that is found between them

is sufficient to tell us that these in many cases exist) custom has doubtless

greatly mitigated them, while it has also helped us to avoid, or insensibly

corrected a number against which mere foresight would have found it difficult

to guard. And finally the imperfections are almost always more supportable

than would be the process of removing them, just as the great roads which

wind about amongst the mountains become, because of being frequented, little

by little so well beaten and easy that it is much better to follow them

than to try to go more directly by climbing over rocks and descending to

the foot of precipices. 



This is the reason why I cannot in any way approve of those turbulent

and unrestful spirits who, being called neither by birth nor fortune to

the management of public affairs, never fail to have always in their minds

some new reforms. And if I thought that in this treatise there was contained

the smallest justification for this folly, I should be very sorry to allow

it to be published. My design thus never extended beyond trying to reform

my own opinion and to build on a foundation which is entirely my own. If

my work has given me a certain satisfaction, so that I here present to

you a draft of it, I do not so do because I wish to advise anybody to imitate

it. Those to whom God has been most beneficent in the bestowal of His graces

will perhaps form designs which are more elevated; but I fear much that

this particular one will seem too venturesome for many. The simple resolve

to strip myself of all opinions and beliefs formerly received is not to

be regarded as an example that each man should follow, and the world may

be said to be mainly composed of those classes of minds neither of which

could prudently adopt it. There are those who believing themselves to be

cleverer than they are, cannot restrain themselves from being precipitate

in judgment and have not sufficient patience to arrange their thoughts

in proper order; hence, once a man of this description had taken the liberty

of doubting the principles he formerly accepted, and had deviated from

the beaten track, he would never be able to maintain the path which must

be followed to reach the appointed end more quickly, and he would hence

remain wandering astray all through his life. Secondly, there are those

who having reason or modesty enough to judge that they are less capable

of distinguishing truth from falsehood than some others from whom instruction

might be obtained, are right in contenting themselves with following the

opinions of these others rather than in searching better ones for themselves.





For myself I should doubtless have been of these last if I had never

had more than a single master, or had I never known the diversities which

have from all time existed between the opinions of men of the greatest

learning. But I had been taught, even in my college days, that there is

nothing imaginable so strange or so little credible that it has not been

maintained by one philosopher or other, and I further recognised in the

course of my travels that all those whose sentiments are very contrary

to ours are yet not necessarily barbarians or savages, but may be possessed

of reason in as great or even a greater degree than ourselves. I also considered

how very different the self-same man, identical in mind and spirit, may

become, according as he is brought up from childhood amongst the French

or Germans, or has passed his whole life amongst Chinese or cannibals.

I likewise noticed how even in the fashions of one's clothing the same

thing that pleased us ten years ago, and which will perhaps please us once

again before ten years are passed, seems at the present time extravagant

and ridiculous. I thus concluded that it is much more custom and example

that persuade us than any certain knowledge, and yet in spite of this the

voice of the majority does not afford a proof of any value in truths a

little difficult to discover, because such truths are much more likely

to have been discovered by one man than by a nation. I could not, however,

put my finger on a single person whose opinions seemed preferable to those

of others, and I found that I was, so to speak, constrained myself to undertake

the direction of my procedure. 



But like one who walks alone and in the twilight I resolved to go so

slowly, and to use so much circumspection in all things, that if my advance

was but very small, at least I guarded myself well from falling. I did

not wish to set about the final rejection of any single opinion which might

formerly have crept into my beliefs without having been introduced there

by means of Reason, until I had first of all employed sufficient time in

planning out the task which I had undertaken, and in seeking the true Method

of arriving at a knowledge of all the things of which my mind was capable.





Among the different branches of Philosophy, I had in my younger days

to a certain extent studied Logic; and in those of Mathematics, Geometrical

Analysis and Algebra - three arts or sciences which seemed as though they

ought to contribute something to the design I had in view. But in examining

them I observed in respect to Logic that the syllogisms and the greater

part of the other teaching served better in explaining to others those

things that one knows (or like the art of Lully, in enabling one to speak

without judgment of those things of which one is ignorant) than in learning

what is new. And although in reality Logic contains many precepts which

are very true and very good, there are at the same time mingled with them

so many others which are hurtful or superfluous that it is almost as difficult

to separate the two as to draw a Diana or a Minerva out of a block of marble

which is not yet roughly hewn. And as to the Analysis of the ancients and

the Algebra of the moderns, besides the fact that they embrace only matters

the most abstract, such as appear to have no actual use, the former is

always so restricted to the consideration of symbols that it cannot exercise

the Understanding without greatly fatiguing the Imagination; and in the

latter one is so subjected to certain rules and formulas that the result

is the construction of an art which is confused and obscure, and which

embarrasses the mind, instead of a science which contributes to its cultivation.

This made me feel that some other Method must be found, which, comprising

the advantages of the three, is yet exempt from their faults. And as a

multiplicity of laws often furnishes excuses for evil-doing, and as a State

is hence much better ruled when, having but very few laws, these are most

strictly observed; so, instead of the great number of precepts of which

Logic is composed, I believed that I should find the four which I shall

state quite sufficient, provided that I adhered to a firm and constant

resolve never on any single occasion to fail in their observance. 



The first of these was to accept nothing as true which I did not clearly

recognise to be so: that is to say, carefully to avoid precipitation and

prejudice in judgments and to accept in them nothing more than what was

presented to my mind so clearly and distinctly that I could have no occasion

to doubt it. 



The second was to divide up each of the difficulties which I examined

into as many parts as possible, and as seemed requisite in order that it

might be resolved in the best manner possible. 



The third was to carry on my reflections in due order, commencing with

objects that were the most simple and easy to understand, in order to rise

little by little, or by degrees, to knowledge of the most complex, assuming

an order, even if a fictitious one, among those which do not follow a natural

sequence relatively to one another. 



The last was in all cases to make enumerations so complete and reviews

so general that I should be certain of having omitted nothing. 



Those long chains of reasoning, simple and easy as they are, of which

geometricians make use in order to arrive at the most difficult demonstrations,

had caused me to imagine that all those things which fall under the cognisance

of man might very likely be mutually related in the same fashion; and that,

provided only that we abstain from receiving anything as true which is

not so, and always retain the order which is necessary in order to deduce

the one conclusion from the other, there can be nothing so remote that

we cannot reach to it, nor so recondite that we cannot discover it. And

I had not much trouble in discovering which objects it was necessary to

begin with, for I already knew that it was with the most simple and those

most easy to apprehend. Considering also that of all those who have hitherto

sought for the truth in the Sciences, it has been the mathematicians alone

who have been able to succeed in making any demonstrations, that is to

say producing reasons which are evident and certain, I did not doubt that

it had been by means of a similar kind that they carried on their investigations.

I did not at the same time hope for any practical result in so doing, except

that my mind would become accustomed to the nourishment of truth and would

not content itself with false reasoning. But for all that I had no intention

of trying to master all those particular sciences that receive in common

the name of Mathematics; but observing that, although their objects are

different, they do not fail to agree in this, that they take nothing under

consideration but the various relationships or proportions which are present

in these objects, I thought that it would be better if I only examined

these proportions in their general aspect, and without viewing them otherwise

than in the objects which would serve most to facilitate a knowledge of

them. Not that I should in any way restrict them to these objects, for

I might later on all the more easily apply them to all other objects to

which they were applicable. Then, having carefully noted that. in order

to comprehend the proportions I should sometimes require to consider each

one in particular, and sometimes merely keep them in mind, or take them

in groups, I thought that, in order the better to consider them in detail,

I should picture them in the form of lines, because I could find no method

more simple nor more capable of being distinctly represented to my imagination

and senses. I considered, however, that in order to keep them in my memory

or to embrace several at once, it would be essential that I should explain

them by means of certain formulas, the shorter the better. And for this

purpose it was requisite that I should borrow all that is best in Geometrical

Analysis and Algebra, and correct the errors of the one by the other. 



As a matter of fact, I can venture to say that the exact observation

of the few precepts which I had chosen gave me so much facility in sifting

out all the questions embraced in these two sciences, that in the two or

three months which I employed in examining them - commencing with the most

simple and general, and making each truth that I discovered a rule for

helping me to find others - not only did I arrive at the solution of many

questions which I had hitherto regarded as most difficult, but, towards

the end, it seemed to me that I was able to determine in the case of those

of which I was still ignorant, by what means, and in how far, it was possible

to solve them. In this I might perhaps appear to you to be very vain if

you did not remember that having but one truth to discover in respect to

each matter, whoever succeeds in finding it knows in its regard as much

as can be known. It is the same as with a child, for instance, who has

been instructed in Arithmetic and has made an addition according to the

rule prescribed; he may be sure of having found as regards the sum of figures

given to him all that the human mind can know. For, in conclusion, the

Method which teaches us to follow the true order and enumerate exactly

every term in the matter under investigation contains everything which

gives certainty to the rules of Arithmetic. 



But what pleased me most in this Method was that I was certain by its

means of exercising my reason in all things, if not perfectly, at least

as well as was in my power And besides this, I felt in making use of it

that my mind gradually accustomed itself to conceive of its objects more

accurately and distinctly; and not having restricted this Method to any

particular matter, I promised myself to apply it as usefully to the difficulties

of other sciences as I had done to those of Algebra. Not that on this account

I dared undertake to examine just at once all those that might present

themselves; for that would itself have been contrary to the order which

the Method prescribes. But having noticed that the knowledge of these difficulties

must be dependent on principles derived from Philosophy in which I yet

found nothing to be certain, I thought that it was requisite above all

to try to establish certainty in it. I considered also that since this

endeavour is the most important in all the world and that which precipitation

and prejudice were most to be feared, I should not try to grapple with

it till I had attained to a much riper age than that of three and twenty,

which was the age I had reached. I thought, too, that I should first of

all employ much time in preparing myself for the work by eradicating from

my mind all the wrong opinions which I had up to this time accepted, and

accumulating a variety of experiences fitted later on to afford matter

for my reasonings, and by ever exercising myself in the Method which I

had prescribed, in order more and more to fortify myself in the power of

using it. 



PART III.



And finally, as it is not sufficient, before commencing to rebuild the

house which we inhabit, to put it down and provide materials and an architect

(or to act in this capacity ourselves, and make a careful drawing of its

design), unless vs-e have also provided ourselves with some other house

where we can be comfortably lodged during the time of rebuilding, so in

order that I should not remain irresolute in my notions while reason obliged

me to be so in my judgments, and that I might not omit to carry on my life

as happily as I could, I formed for myself a code of morals for the time

being which did not consist of more than three or four maxims, which maxims

I should like to enumerate to you. 



The first was to obey the laws and customs of my country, adhering constantly

to the religion in which by God's grace I had been instructed since my

childhood, and in all other things directing my conduct by opinions the

most moderate in nature, and the farthest removed from excess in all those

which are commonly received and acted on by the most judicious of those

with whom I might come in contact. For since I began to count my own opinions

as nought, because I desired to place all under examination, I was convinced

that I could not do better than follow those held by people on whose judgment

reliance could be placed. And although such persons may possibly exist

amongst the Persians and Chinese as well as amongst ourselves, it seemed

to me that it was most expedient to bring my conduct into harmony with

the ideas of those with whom I should have to live; and that, in order

to ascertain that these were their real opinions, I should observe what

they did rather than what they said, not only because in the corrupt state

of our manners there are few people who desire to say all that they believe,

but also because many are themselves ignorant of their beliefs. For since

the act of thought by which we believe a thing is different from that by

which we know that we believe it, the one often exists without the other.

And amongst many opinions all equally received, I chose only the most moderate,

both because these are always most suited for putting into practice, and

probably the best (for all excess has a tendency to be bad), and also because

I should have in a less degree turned aside from the right path, supposing

that I was wrong, than if, having chosen an extreme course, I found that

I had chosen amiss. I also made a point of counting as excess all the engagements

by means of which we limit in some degree our liberty. Not that I hold

in low esteem those laws which, in order to remedy the inconstancy of feeble

souls, permit, when we have a good object in our view, that certain vows

be taken, or contracts made, which oblige us to carry out that object.

This sanction is even given for security in commerce where designs are

wholly indifferent. But because I saw nothing in all the world remaining

constant, and because for my own part I promised myself gradually to get

my judgments to grow better and never to grow worse, I should have thought

that I had committed a Serious ill against commonsense if, because I approved

of something at one time, I was obliged to regard it similarly at a later

time, after it had possibly ceased to meet my approval, or after I had

ceased to regard it in a favourable light. 



My second maxim was that of being as firm and resolute in my actions

as I could be, and not to follow less faithfully opinions the most dubious,

when my mind was once made up regarding them, than if these had been beyond

doubt. In this I should be following the example of travellers, who, finding

themselves lost in a forest, know that they ought not to wander first to

one side and then to the other, nor, still less, to stop in one place,

but understand that they should continue to walk as straight as they can

in one direction, not diverging for any slight reason, even though it was

possibly chance alone that first determined them in their choice. By this

means if they do not go exactly where they wish, they will at least arrive

somewhere at the end, where probably they will be better off than in the

middle of a forest. And thus since often enough in the actions of life

no delay is permissible, it is very certain that, when it is beyond our

power to discern the opinions which carry most truth, we should follow

the most probable; and even although we notice no greater probability in

the one opinion than in the other, we at least should make up our minds

to follow a particular one and afterwards consider it as no longer doubtful

in its relationship to practice, but as very true and very certain, inasmuch

as the reason which caused us to determine upon it is known to be so. And

henceforward this principle was sufficient to deliver me from all the penitence

and remorse which usually affect the mind and agitate the conscience of

those weak and vacillating creatures who allow themselves to keep changing

their procedure, and practise as good, things which they afterwards judge

to be evil. 



My third maxim was to try always to conquer myself rather than fortune,

and to alter my desires rather than change the order of the world, and

generally to accustom myself to believe that there is nothing entirely

within our power but our own thoughts: so that after we have done our best

in regard to the things that are without us, our ill-success cannot possibly

be failure on our part. And this alone seemed to me sufficient to prevent

my desiring anything in the future beyond what I could actually obtain,

hence rendering me content; for since our will does not naturally induce

us to desire nothing but what our understanding represents to it as in

some way possible of attainment, it is certain that if we consider all

good things Which are outside of us as equally outside of our power, we

should not have more regret in resigning those goods which appear to pertain

to our birth, when we are deprived of them for no fault of our own, than

we have in not possessing the kingdoms of China or Mexico. In the same

way, in making what is called a virtue out of a necessity, we should no

more desire to be well if ill, or free, if in prison, than we now do to

have our bodies formed of a substance as little corruptible as diamonds,

or to have wings to fly with like birds. I allow, however, that to accustom

oneself to regard all things from this point of view requires long exercise

and meditation often repeated; and I believe that it is principally ill

this that is to be found the secret of those philosophers who, in ancient

times, were able to free themselves from the empire of fortune, or, despite

suffering or poverty, to rival their gods in their happiness. For, ceaselessly

occupying themselves in considering the limits which were prescribed to

them by nature, they persuaded themselves so completely that nothing was

within their own power but their thoughts, that this conviction alone was

sufficient to prevent their having any longing for other things. And they

had so absolute a mastery over their thoughts that they had some reason

for esteeming themselves as more rich and more powerful, and more free

and more happy than other men, who, however favoured by nature or fortune

they might be, if devoid of this philosophy, never could arrive at all

at which they aim. 



And last of all, to conclude this moral code, I felt it incumbent on

me to make a review of the various occupations of men in this life in order

to try to choose out the best; and without wishing to say anything of the

employment of others I thought that I could not do better than continue

in the one in which I found myself engaged, that is to say, in occupying

my whole life in cultivating Reason, and in advancing myself as much as

possible in the knowledge of the truth in accordance with the method which

I had prescribed myself. I had experienced so much satisfaction since beginning

to use this method, that I did not believe that any sweeter or more innocent

could in this life be found, - every day discovering by its means some

truths which seemed to me sufficiently important, although commonly ignored

by other men. The satisfaction which I had so filled my mind that all else

seemed of no account, besides, the three preceding maxims were founded

solely on the plan which I had formed of continuing to instruct myself.

For since God has given to each of us some light with which to distinguish

truth from error, I could not believe that I ought for a single moment

to content myself with accepting the opinions held by others unless I had

in view the employment of my own judgment in examining them at the proper

time; and I could not have held myself free of scruple in following such

opinions, if nevertheless I had not intended to lose no occasion of finding

superior opinions, supposing them to exist; and finally, I should not have

been able to restrain my desires nor to remain content, if I had not followed

a road by which, thinking that I should be certain to be able to acquire

all the knowledge of which I was capable, I also thought I should likewise

be certain of obtaining all the best things which could ever come within

my power. And inasmuch as our will impels us neither to follow after nor

to flee from anything, excepting as our understanding represents it as

good or evil, it is sufficient to judge wisely in order to act well, and

the best judgment brings the best action - that is to say, the acquisition

of all the virtues and all the other good things that it is possible to

obtain. When one is certain that this point is reached, one cannot fail

to be contented. 



Having thus assured myself of these maxims, and having set them on one

side along with the truths of religion which have always taken the first

place in my creed, I judged that as far as the rest of my opinions were

concerned, I could safely undertake to rid myself of them. .And inasmuch

as I hoped to hoped to reach my end more successfully in converse with

man than in living longer shut up in the warm room where these reflections

had come to me I hardly awaited the end of winter before I once more set

myself to travel. And in all the nine following years I did nought but

roam hither and thither, trying to he a spectator rather than an actor

in all the comedies the world displays. More especially did I reflect in

each matter that came before me as to anything which could make it subject

to suspicion or doubt, and give occasion for mistake, and I rooted out

of my mind all the errors which might have formerly crept in. Not that

indeed I imitated the sceptics, who only doubt for the sake of doubting,

and pretend to be always uncertain; for, on the contrary, my design was

only to provide myself with good ground for assurance, and to reject the

quicksand and mud in order to find the rock or clay. In this task it seems

to me, I succeeded pretty well, since in trying to discover the error or

uncertainty of the propositions which I examined, not by feeble conjectures,

but by clear and assured reasonings, I encountered nothing so dubious that

I could not draw from it some conclusion that was tolerably secure, if

this were no more than the inference that it contained in it nothing that

vas certain. And just as in pulling down an old house we usually preserve

the debris to serve in building up another, so ill destroying all those

opinions which I considered to be ill-founded, I made various observations

and acquired many experiences, which have since been of use to me in establishing

those which are more certain. And more than this, I continued to exercise

myself in the method which I had laid down for my use; for besides the

fact that I was careful as a rule to conduct all my thoughts according

to its maxims, I set aside some hours from time to time which I more especially

employed in practising myself in the solution of mathematical problems

according to the Method, or the solution of other problems which though

pertaining to other sciences, I was able to make almost similar to those

of mathematics, by detaching them from all principles of other sciences

which I found to be not sufficiently secure. You will see the result in

many examples which are expounded in this volume. And hence, without living

to all appearance in any way differently from those who, having no occupation

beyond spending their lives in ease and innocence, study to separate pleasure

from vice, and who, in order to enjoy their leisure without weariness,

make use of all distractions that are innocent and good, I did not cease

to prosecute my design, and to profit perhaps even more in my study of

truth than if I had done nothing but read books or associate with literary

people. 



These nine years thus passed away before I had taken any definite part

in regard to the difficulties as to which the learned are in the habit

of disputing, or had commenced to seek the foundation of any philosophy

more certain than the vulgar. And the example of many excellent men who

had tried to do the same before me, but, as it appears to me, without success,

made me imagine it to be so hard that possibly I should not have dared

to undertake the task, had I not discovered that someone hand spread abroad

the report that I had already reached its conclusion. I cannot tell on

what they based this opinion; if my conversation has contributed anything

to it, this must have arisen from my confessing my ignorance more ingenuously

than those who have studied a little usually do. And perhaps it was also

due to my having shown forth my reasons for doubting many things which

were held by others to be certain, rather than from having boasted of any

special philosophic system. But being at heart honest enough not to desire

to be esteemed as different from what I am, I thought that I must try by

every means in my power to render myself worthy of the reputation which

I had gained. And it is just eight years ago that this desire made me resolve

to remove myself from all places where any acquaintances were possible,

and to retire to a country such as this, where the long-continued war has

caused such order to be established that the armies which are maintained

seem only to be of use in allowing the inhabitants to enjoy the fruits

of peace with so much the more security; and where, in the crowded throng

of a great and very active nation, which is more concerned with its own

affairs than curious about those of others, without missing any of the

conveniences of the most populous towns, I can live as solitary and retired

as in deserts the most remote. 



PART IV.



I do not know that I ought to tell you of the first meditations there

made by me, for they are so metaphysical and so unusual that they may perhaps

not be acceptable to everyone. And yet at the same time, in order that

one may judge whether the foundations which I have found are sufficiently

secure, I find myself constrained in some measure to refer to them. For

a long time I had remarked that it is sometimes requisite in common life

to follow opinions which one knows to be most uncertain, exactly as though

they were indisputable, as has been said above. But because in this case

I wished to give myself entirely to the search after truth, I thought that

it was necessary for me to take an -apparently opposite course, and to

reject as absolutely false everything as to which I could imagine the least

ground of doubt, in order to see if afterwards there remained anything

in my belief that was entirely certain. This, because our senses sometimes

deceive us, I wished to suppose that nothing is just as they cause us to

imagine it to be; and because there are men who deceive themselves in their

reasoning and fall into paralogisms, even concerning the simplest matters

of geometry, and judging that I was as subject to error as was any other,

I rejected as false all the reasons formerly accepted by me as demonstrations.

And since all the same thoughts and conceptions which we have while awake

may also come to us in sleep, without any of them being at that time true,

I resolved to assumed that everything that ever entered into my mind was

no more true than the illusions of my dreams. But immediately afterwards

I noticed that whilst I thus wished to think all things false, it was absolutely

essential that the ' I ' who thought this should be somewhat, and remarking

that this truth "I think therefore I am" was so certain

and so assured that all the most extravagant suppositions brought forward

by the sceptics were incapable of shaking it, I came to the conclusion

that I could receive it without scruple as the first principle of the Philosophy

for which I was seeking. 



And then, examining attentively that which I was, I saw that I could

conceive that I had no body, and that there was no world nor place where

I might be; but yet that I could not for all that conceive that I was not.

On the contrary, I saw from the very fact that I thought of doubting the

truth of other things, it very evidently and certainly followed that I

was; on the other hand if I had only ceased from thinking, even if all

the rest of what I had ever imagined had really existed, I should have

no reason for thinking that I had existed. From that I knew that I was

a substance the whole essence or nature of which is to think, and that

for its existence there is no need of any place, nor does it depend on

any material thing; so that this ' me,' that is to say, the soul by which

I am what I am, is entirely distinct from body, and is even more easy to

know than is the latter; and even if body were not, the soul would not

cease to be what it is. 



After this I considered generally what in a proposition is requisite

in order to be true and certain; for since I had just discovered one which

I knew to be such, I thought that I ought also to know in what this certainty

consisted. And having remarked that there was nothing at all in the statement

"I think, therefore I am" which assures me of having thereby

made a true assertion, excepting that I see very clearly that to think

it is necessary to be, I came to the conclusion that I might assume, as

a general rule, that the things which we conceive very clearly and distinctly

are all true - remembering, however, that there is some difficulty in ascertaining

which are those that we distinctly conceive. 



Following upon this, and reflecting on the fact that I doubted, and

that consequently my existence was not quite perfect (for I saw clearly

that it was a greater perfection to know than to doubt), I resolved to

inquire whence I had learnt to think of anything more perfect than I myself

was; and I recognised very clearly that this conception must proceed from

some nature which was really more perfect. As to the thoughts which I had

of many other things outside of me, like the heavens, the earth, light,

heat, and a thousand others, I had not so much difficulty in knowing whence

they came, because, remarking nothing in them which seemed to render them

superior to me, I could believe that, if they were true, they were dependencies

upon my nature, in so far as it possessed some perfection; and if they

were not true, that I held them from nought, that is to say, that they

were in me because I had something lacking in my nature. But this could

not apply to the idea of a Being more perfect than my own, for to hold

it from nought would be manifestly impossible; and because it is no less

contradictory to say of the more perfect that it is what results from and

depends on the less perfect, than to say that there is something which

proceeds from nothing, it was equally impossible that I should hold it

from myself. In this way it could but follow that it had been placed in

me by a Nature which was really more perfect than mine could be, and which

even had within itself all the perfections of which I could form any idea

- that is to say, to put it in a word, which was God. To which I added

that since I knew some perfections which I did not possess, I was not the

only being in existence (I shall here use freely, if you will allow, the

terms of the School); but that there was necessarily some other more perfect

Being on which I depended, or from which I acquired all that I had. For

if I had existed alone and independent of any others, so that I should

have had from myself all that perfection of being in which I participated

to however small an extent, I should have been able for the same reason

to have had all the remainder which I knew that I lacked; and thus I myself

should have been infinite eternal, immutable, omniscient, all-powerful,

and, finally, I should have all the perfections which I could discern in

God. For, in pursuance of the reasonings which I have just carried on,

in order to know the nature of God as far as my nature is capable of knowing

it, I had only to consider in reference to all these things of which I

found some idea in myself, whether it was a perfection to possess them

or not. And I was assured that none of those which indicated some imperfection

were in Him, but that all else was present; and I saw that doubt, inconstancy,

sadness, and such things, could not be in Him considering that I myself

should have been glad to be without them. In addition to this, I had ideas

of many things which are sensible and corporeal, for, although I might

suppose that I was dreaming, and that all that I saw or imagined was false,

I could not at the same time deny that the ideas were really in my thoughts.

But because I had already recognised very clearly in myself that the nature

of the intelligence is distinct from that of the body, and observing that

all composition gives evidence of dependency, and that dependency is manifestly

an imperfection, I came to the conclusion that it could not be a perfection

in God to be composed of these two natures, and that consequently He was

not so composed. I judged, however, that if there were any bodies in the

world, or even any intelligences or other natures which were not wholly

perfect, their existence must depend on His power in I such a way that

they could not subsist without Him for a single moment. 



After that I desired to seek for other truths, and having put before

myself the object of the geometricians, which I conceived to be a continuous

body, or a space indefinitely extended in length, breadth, height or depth,

which was divisible into various parts, and which might have various figures

and sizes, and might be moved or transposed in all sorts of ways (for all

this the geometricians suppose to be in the object of their contemplation)

I went through some of their simplest demonstrations, and having noticed

that this great certainty which everyone attributes to these demonstrations

is founded solely on the fact that they are conceived of with clearness,

in accordance with the rule which I have just laid down, I also noticed

that there was nothing at all in them to assure me of the existence of

their object. For, to take an example, I saw very well that if we suppose

a triangle to be given, the three angles must certainly be equal to two

right angles, but for all that I saw no reason to be assured that there

was any such triangle in existence, while on the contrary, on reverting

to the examination of the idea which I had of a Perfect Being, I found

that in this case existence was implied in it in the same manner in which

the equality of its three angles to two right angles is implied in the

idea of a triangle; or in the idea of a sphere, that all the points on

its surface are equidistant from its centre, or even more evidently still.

Consequently it is at least as certain that God, who is a Being so perfect,

is, or exists, as any demonstration of geometry could possibly be. 



What causes many, however, to persuade themselves that there is difficulty

in knowing this truth, and even in knowing the nature of their soul, is

the fact that they never raise their minds above the things of sense, or

that they are so accustomed to consider nothing excepting by imagining

it, which is a mode of thought specially adapted to material objects, that

all that is not capable of being imagined appears to them not to be intelligible

at all. This is manifest enough from the fact that even the philosophers

in the Schools hold it as a maxim that there is nothing in the understanding

which has not first of all been in the senses, in which there is certainly

no doubt that the ideas of God and of the soul have never been. And it

seems to me that those who desire to make use of their imagination in order

to understand these ideas, act in the same way as if, to hear sounds or

smell odours, they should wish to make use of their eyes: excepting that

there is indeed this difference, that the sense of sight does not give

us less assurance of the truth of its objects, than do those of scent or

of hearing, while neither our imagination not our senses can ever assure

us of anything, if our understanding does not intervene. 



If there are finally any persons who are not sufficiently persuaded

of the existence of God and of their soul by the reasons which I have brought

forward, I wish that they should know that all other things of which they

perhaps think themselves more assured (such as possessing a body, and that

there are stars and an earth and so on) are less certain. For, although

we have a moral assurance of these things which is such that it seems that

it would be extravagant in us to doubt them, at the same time no one, unless

he is devoid of reason, can deny, when a metaphysical certainty is in question,

that there is sufficient cause for our not having complete assurance, by

observing the fact that when asleep we may similarly imagine that we have

another body, and that we see other stars and another earth, without there

being anything, of the kind. 



For how do we know that the thoughts that come in dreams are more false

than those that we have when we are awake, seeing that often enough the

former are not less lively and vivid than the latter And though the wisest

minds may study the matter as much as they will, I do not believe that

they will be able to give any sufficient reason for removing this doubt,

unless they presuppose the existence of God. For to begin with, that which

I have just taken as a rule, that is to say, that all the things that we

very clearly and very distinctly conceive of are true, is certain only

because God is or exists, and that He is a. Perfect Being, and that all

that is in us issues from Him. From this it follows that our ideas or notions,

which to the extent of their being clear or distinct are ideas of real

things issuing from God, cannot but to that extent be true. So that though

we often enough have ideas which have an element of falsity, this can only

be the case in regard to those which have in them somewhat that is confused

or obscure, because in so far as they have this character they participate

in negation - that is, they exist in us as confused only because we are

not quite perfect. And it is evident that there is no less repugnance in

the idea that error or imperfection, inasmuch as it is imperfection, proceeds

from God, than there is in the idea of truth or perfection proceeding from

nought. But if we did not know that all that is in us of reality and truth

proceeds from a perfect and infinite Being, however clear and distinct

were our ideas, we should not have any reason to assure ourselves that

they had the perfection of being true. 



But after the knowledge of God and of the soul has thus rendered us

certain of this rule, it is very easy to understand that the dreams which

we imagine in our sleep should not make us in any way doubt the truth of

the thoughts which we have when awake. For even if in sleep we had some

very distinct idea such as a geometrician might have who discovered some

new demonstration the fact of being asleep would not annihilate against

its truth. And as to the most ordinary error in our dreams, which consists

in their representing to us various objects in the same way as do our external

senses, it does not matter that this should give us occasion to suspect

the truth of such ideas, because we may be likewise often enough deceived

in them without our sleeping at all, just as when those who have the jaundice

see everything as yellow, or when stars or other bodies which are very

remote appear much smaller than they really are, or, finally, whether we

are awake or asleep, we should never allow ourselves to be persuaded excepting

by the evidence of our Reason. And it must be remarked that I speak of

our Reason and not of our imagination nor of our senses; just as though

we see the sun very clearly, we should not for that reason judge that it

is of the size of which it appears to be; likewise we could quite well

distinctly imagine the head of a lion on the body of a goat, without necessarily

concluding that a chimera exists. For Reason does not insist that whatever

we see or imagine thus is a truth, but it tells us clearly that all our

ideas or notions must have some foundation of truth. For otherwise it could

not be possible that God, who is all perfection and truth, should have

placed them within us. And because our reasonings are never so evident

nor so complete during sleep as during wakefulness, although sometimes

our imaginations are then just as lively and acute, or even more so, Reason

tells us that since our thoughts cannot possibly be all true, because we

are not altogether perfect, that which they have of truth must infallibly

be met with in our waking experience rather than in that of our dreams.





PART V.



I should be very glad to proceed to show forth the complete chain of

truths which I have deduced from these first, but because to do this it

would have been necessary now to speak of many matters of dispute among

the learned, with whom I have no desire to embroil myself, I think that

it will be better to abstain. I shall only state generally what these truths

are, so that it may be left to the decision of those best able to judge

whether it would be of use for the public to be more particularly informed

of them or not. I always remained firm in the resolution which I had made,

nor to assume any other principle than that of which I have just made use,

in order to demonstrate the existence of God and of the Soul, and to accept

nothing as true which did not appear to be more clear and more certain

than the demonstrations of the geometricians had formerly seemed. And nevertheless

I venture to say that not only have I found the means of satisfying myself

in a short time as to the more important of those difficulties usually

dealt with in philosophy, but I have also observed certain laws which God

has so established in Nature, and of which He has imprinted such ideas

on our minds, that, after having reflected sufficiently upon the matter,

we cannot doubt their being accurately observed in all that exists or is

alone in the world. Further, in considering the sequence of these laws,

it seems to me that I have discovered many things more useful and more

important than all that I had formerly learned or even hoped to learn.





But because I tried to explain the most important of these in a Treatise

which certain considerations prevented me from publishing I cannot do better,

in making them known, than here summarise briefly what that Treatise contains.

I had planned to comprise in it all that I believed myself to know regarding

the nature of material objects, before I set myself to write. ... 

Source: Discourse on Method (1637). Cambridge Univesity Press, edited Haldane and Ross; first five parts.