I was then in Germany, attracted thither by the wars in that country which have not yet been brought to a termination; and as I wa returning to the army from the coronation of the emperor, the settin in of winter arrested me in a locality where, as I found no society t interest me, and was besides fortunately undisturbed by any cares o passions, I remained the whole day in seclusion, with full opportunit to occupy my attention with my own thoughts. Of these one of the ver first that occurred to me was, that there is seldom so much perfectio in works composed of many separate parts, upon which different hand had been employed, as in those completed by a single master. Thus i is observable that the buildings which a single architect has planne and executed, are generally more elegant and commodious than thos which several have attempted to improve, by making old walls serve fo purposes for which they were not originally built. Thus also, thos ancient cities which, from being at first only villages, have become in course of time, large towns, are usually but ill laid out compare with the regularity constructed towns which a professional architec has freely planned on an open plain; so that although the severa buildings of the former may often equal or surpass in beauty those o the latter, yet when one observes their indiscriminate juxtaposition there a large one and here a small, and the consequent crookedness an irregularity of the streets, one is disposed to allege that chanc rather than any human will guided by reason must have led to such a arrangement. And if we consider that nevertheless there have been a all times certain officers whose duty it was to see that privat buildings contributed to public ornament, the difficulty of reachin high perfection with but the materials of others to operate on, will b readily acknowledged. In the same way I fancied that those nation which, starting from a semi-barbarous state and advancing t civilization by slow degrees, have had their laws successivel determined, and, as it were, forced upon them simply by experience o the hurtfulness of particular crimes and disputes, would by thi process come to be possessed of less perfect institutions than thos which, from the commencement of their association as communities, hav followed the appointments of some wise legislator. It is thus quit certain that the constitution of the true religion, the ordinances o which are derived from God, must be incomparably superior to that o every other. And, to speak of human affairs, I believe that th pre-eminence of Sparta was due not to the goodness of each of its law in particular, for many of these were very strange, and even opposed t good morals, but to the circumstance that, originated by a singl individual, they all tended to a single end. In the same way I though that the sciences contained in books (such of them at least as are mad up of probable reasonings, without demonstrations), composed as the are of the opinions of many different individuals massed together, ar farther removed from truth than the simple inferences which a man o good sense using his natural and unprejudiced judgment draws respectin the matters of his experience. And because we have all to pass throug a state of infancy to manhood, and have been of necessity, for a lengt of time, governed by our desires and preceptors (whose dictates wer frequently conflicting, while neither perhaps always counseled us fo the best), I farther concluded that it is almost impossible that ou judgments can be so correct or solid as they would have been, had ou reason been mature from the moment of our birth, and had we always bee guided by it alone

It is true, however, that it is not customary to pull down all th houses of a town with the single design of rebuilding them differently and thereby rendering the streets more handsome; but it often happen that a private individual takes down his own with the view of erectin it anew, and that people are even sometimes constrained to this whe their houses are in danger of falling from age, or when the foundation are insecure. With this before me by way of example, I was persuade that it would indeed be preposterous for a private individual to thin of reforming a state by fundamentally changing it throughout, an overturning it in order to set it up amended; and the same I though was true of any similar project for reforming the body of the sciences or the order of teaching them established in the schools: but as fo the opinions which up to that time I had embraced, I thought that could not do better than resolve at once to sweep them wholly away that I might afterwards be in a position to admit either others mor correct, or even perhaps the same when they had undergone the scrutin of reason. I firmly believed that in this way I should much bette succeed in the conduct of my life, than if I built only upon ol foundations, and leaned upon principles which, in my youth, I had take upon trust. For although I recognized various difficulties in thi undertaking, these were not, however, without remedy, nor once to b compared with such as attend the slightest reformation in publi affairs. Large bodies, if once overthrown, are with great difficult set up again, or even kept erect when once seriously shaken, and th fall of such is always disastrous. Then if there are any imperfection in the constitutions of states (and that many such exist the diversit of constitutions is alone sufficient to assure us), custom has withou doubt materially smoothed their inconveniences, and has even managed t steer altogether clear of, or insensibly corrected a number whic sagacity could not have provided against with equal effect; and, i fine, the defects are almost always more tolerable than the chang necessary for their removal; in the same manner that highways whic wind among mountains, by being much frequented, become gradually s smooth and commodious, that it is much better to follow them than t seek a straighter path by climbing over the tops of rocks an descending to the bottoms of precipices

Hence it is that I cannot in any degree approve of those restless an busy meddlers who, called neither by birth nor fortune to take part i the management of public affairs, are yet always projecting reforms and if I thought that this tract contained aught which might justif the suspicion that I was a victim of such folly, I would by no mean permit its publication. I have never contemplated anything higher tha the reformation of my own opinions, and basing them on a foundatio wholly my own. And although my own satisfaction with my work has le me to present here a draft of it, I do not by any means therefor recommend to every one else to make a similar attempt. Those whom Go has endowed with a larger measure of genius will entertain, perhaps designs still more exalted; but for the many I am much afraid lest eve the present undertaking be more than they can safely venture t imitate. The single design to strip one's self of all past beliefs i one that ought not to be taken by every one. The majority of men i composed of two classes, for neither of which would this be at all befitting resolution: in the first place, of those who with more tha a due confidence in their own powers, are precipitate in thei judgments and want the patience requisite for orderly and circumspec thinking; whence it happens, that if men of this class once take th liberty to doubt of their accustomed opinions, and quit the beate highway, they will never be able to thread the byway that would lea them by a shorter course, and will lose themselves and continue t wander for life; in the second place, of those who, possessed o sufficient sense or modesty to determine that there are others wh excel them in the power of discriminating between truth and error, an by whom they may be instructed, ought rather to content themselves wit the opinions of such than trust for more correct to their own reason

For my own part, I should doubtless have belonged to the latter class had I received instruction from but one master, or had I never know the diversities of opinion that from time immemorial have prevaile among men of the greatest learning. But I had become aware, even s early as during my college life, that no opinion, however absurd an incredible, can be imagined, which has not been maintained by some o of the philosophers; and afterwards in the course of my travels remarked that all those whose opinions are decidedly repugnant to our are not in that account barbarians and savages, but on the contrar that many of these nations make an equally good, if not better, use o their reason than we do. I took into account also the very differen character which a person brought up from infancy in France or German exhibits, from that which, with the same mind originally, thi individual would have possessed had he lived always among the Chines or with savages, and the circumstance that in dress itself the fashio which pleased us ten years ago, and which may again, perhaps, b received into favor before ten years have gone, appears to us at thi moment extravagant and ridiculous. I was thus led to infer that th ground of our opinions is far more custom and example than any certai knowledge. And, finally, although such be the ground of our opinions I remarked that a plurality of suffrages is no guarantee of truth wher it is at all of difficult discovery, as in such cases it is much mor likely that it will be found by one than by many. I could, however select from the crowd no one whose opinions seemed worthy o preference, and thus I found myself constrained, as it were, to use m own reason in the conduct of my life

But like one walking alone and in the dark, I resolved to proceed s slowly and with such circumspection, that if I did not advance far, would at least guard against falling. I did not even choose to dismis summarily any of the opinions that had crept into my belief withou having been introduced by reason, but first of all took sufficient tim carefully to satisfy myself of the general nature of the task I wa setting myself, and ascertain the true method by which to arrive at th knowledge of whatever lay within the compass of my powers

Among the branches of philosophy, I had, at an earlier period, give some attention to logic, and among those of the mathematics t geometrical analysis and algebra,--three arts or sciences which ought as I conceived, to contribute something to my design. But, o examination, I found that, as for logic, its syllogisms and th majority of its other precepts are of avail--rather in th communication of what we already know, or even as the art of Lully, i speaking without judgment of things of which we are ignorant, than i the investigation of the unknown; and although this science contain indeed a number of correct and very excellent precepts, there are nevertheless, so many others, and these either injurious o superfluous, mingled with the former, that it is almost quite a difficult to effect a severance of the true from the false as it is t extract a Diana or a Minerva from a rough block of marble. Then as t the analysis of the ancients and the algebra of the moderns, beside that they embrace only matters highly abstract, and, to appearance, o no use, the former is so exclusively restricted to the consideration o figures, that it can exercise the understanding only on condition o greatly fatiguing the imagination; and, in the latter, there is s complete a subjection to certain rules and formulas, that there result an art full of confusion and obscurity calculated to embarrass, instea of a science fitted to cultivate the mind. By these considerations was induced to seek some other method which would comprise th advantages of the three and be exempt from their defects. And as multitude of laws often only hampers justice, so that a state is bes governed when, with few laws, these are rigidly administered; in lik manner, instead of the great number of precepts of which logic i composed, I believed that the four following would prove perfectl sufficient for me, provided I took the firm and unwavering resolutio never in a single instance to fail in observing them

The first was never to accept anything for true which I did not clearl know to be such; that is to say, carefully to avoid precipitancy an prejudice, and to comprise nothing more in my judgement than what wa presented to my mind so clearly and distinctly as to exclude all groun of doubt

The second, to divide each of the difficulties under examination int as many parts as possible, and as might be necessary for its adequat solution

The third, to conduct my thoughts in such order that, by commencin with objects the simplest and easiest to know, I might ascend by littl and little, and, as it were, step by step, to the knowledge of the mor complex; assigning in thought a certain order even to those object which in their own nature do not stand in a relation of antecedence an sequence

And the last, in every case to make enumerations so complete, an reviews so general, that I might be assured that nothing was omitted

The long chains of simple and easy reasonings by means of whic geometers are accustomed to reach the conclusions of their mos difficult demonstrations, had led me to imagine that all things, to th knowledge of which man is competent, are mutually connected in the sam way, and that there is nothing so far removed from us as to be beyon our reach, or so hidden that we cannot discover it, provided only w abstain from accepting the false for the true, and always preserve i our thoughts the order necessary for the deduction of one truth fro another. And I had little difficulty in determining the objects wit which it was necessary to commence, for I was already persuaded that i must be with the simplest and easiest to know, and, considering that o all those who have hitherto sought truth in the sciences, th mathematicians alone have been able to find any demonstrations, tha is, any certain and evident reasons, I did not doubt but that such mus have been the rule of their investigations. I resolved to commence therefore, with the examination of the simplest objects, no anticipating, however, from this any other advantage than that to b found in accustoming my mind to the love and nourishment of truth, an to a distaste for all such reasonings as were unsound. But I had n intention on that account of attempting to master all the particula sciences commonly denominated mathematics: but observing that, howeve different their objects, they all agree in considering only the variou relations or proportions subsisting among those objects, I thought i best for my purpose to consider these proportions in the most genera form possible, without referring them to any objects in particular except such as would most facilitate the knowledge of them, and withou by any means restricting them to these, that afterwards I might thus b the better able to apply them to every other class of objects to whic they are legitimately applicable. Perceiving further, that in order t understand these relations I should sometimes have to consider them on by one and sometimes only to bear them in mind, or embrace them in th aggregate, I thought that, in order the better to consider the individually, I should view them as subsisting between straight lines than which I could find no objects more simple, or capable of bein more distinctly represented to my imagination and senses; and on th other hand, that in order to retain them in the memory or embrace a aggregate of many, I should express them by certain characters th briefest possible. In this way I believed that I could borrow all tha was best both in geometrical analysis and in algebra, and correct al the defects of the one by help of the other

And, in point of fact, the accurate observance of these few precept gave me, I take the liberty of saying, such ease in unraveling all th questions embraced in these two sciences, that in the two or thre months I devoted to their examination, not only did I reach solution of questions I had formerly deemed exceedingly difficult but even a regards questions of the solution of which I continued ignorant, I wa enabled, as it appeared to me, to determine the means whereby, and th extent to which a solution was possible; results attributable to th circumstance that I commenced with the simplest and most genera truths, and that thus each truth discovered was a rule available in th discovery of subsequent ones Nor in this perhaps shall I appear to vain, if it be considered that, as the truth on any particular point i one whoever apprehends the truth, knows all that on that point can b known. The child, for example, who has been instructed in the element of arithmetic, and has made a particular addition, according to rule may be assured that he has found, with respect to the sum of th numbers before him, and that in this instance is within the reach o human genius. Now, in conclusion, the method which teaches adherenc to the true order, and an exact enumeration of all the conditions o the thing sought includes all that gives certitude to the rules o arithmetic

But the chief ground of my satisfaction with thus method, was th assurance I had of thereby exercising my reason in all matters, if no with absolute perfection, at least with the greatest attainable by me besides, I was conscious that by its use my mind was becoming graduall habituated to clearer and more distinct conceptions of its objects; an I hoped also, from not having restricted this method to any particula matter, to apply it to the difficulties of the other sciences, with no less success than to those of algebra. I should not, however, on thi account have ventured at once on the examination of all th difficulties of the sciences which presented themselves to me, for thi would have been contrary to the order prescribed in the method, bu observing that the knowledge of such is dependent on principle borrowed from philosophy, in which I found nothing certain, I though it necessary first of all to endeavor to establish its principles. An because I observed, besides, that an inquiry of this kind was of al others of the greatest moment, and one in which precipitancy an anticipation in judgment were most to be dreaded, I thought that ought not to approach it till I had reached a more mature age (being a that time but twenty-three), and had first of all employed much of m time in preparation for the work, as well by eradicating from my min all the erroneous opinions I had up to that moment accepted, as b amassing variety of experience to afford materials for my reasonings and by continually exercising myself in my chosen method with a view t increased skill in its application