NEW ESSAYS ON THE UNDERSTANDING BY THE AUTHOR OF THE SYSTEM OF PRE-ESTABLISHED HARMONY PREFACE THE Essay on the Understanding, by a distinguished English man, being one of the most beautiful and esteemed works of this period, I have resolved to make some remarks upon it, because having sufficiently meditated for a long time upon the same subject and upon the greater part of the matters therein touched upon, I have thought that it would be a favorable opportunity to publish something under the title of " New Essays on the Understanding," and to procure a favor able reception to my thoughts, by putting them in so good company. I l have thought also that I could profit from the labor of another not only to lessen my own (since in fact it is less difficult to follow the thread of a good author than to work wholly independently), but further to add something to what he has given us, which is always easier than to start from the beginning; for I think I have cleared up some difficulties which he had left in their entirety. Thus his reputation is an advantage to me; having for the rest a disposition to render justice, and very far from wishing to diminish the esteem in which this work is held, I would increase it, if my approval carried any weight. It is true I often differ in my views (from 1 Gerhardt's text reads as follows: "J'ai cru encor pouvoir profiler du travail d'autruy non seulement pour diminuer le mien (pnisqn'cn effect il y a moins do peine a snivre le fil d'un bon auteur qu'a travailler a nouveaux frais en tout), mais encor ponr adjouter quelque chose a ce qn'il nous a donne, ce qui est tousjours plus facile quo do commencer; car je crois d'avoir leve quelques difficultes qu'il avoit laisse'es en leur entier. Ainsi sa reputation m'est avantaguese; estant d'ailleurs d'humeur a rendre justice et bien loin de vouloir diminuer 1'estime qu'on a pour cet ouvrage, je 1'accroistrois, si mon approbation estoit de quelque poids. II cst vray que je suis souvent d'unautre avis, mais bien loin de disconvenir du merite des Ecrivains celebres, on leur rend tcmoijinase, en faisant connoistre en quoy et pour quoy on s'eloigne de leur sentiment, quand on juge neeessaire d'empecher que lour autorite' ne prevaille a la raison en quelques points de consequence, outre qu'eu satisfaisant a de si excellcns bommes, on rend la verite plus recevable. et il faut supposer que c'est principalement pour elle qu'ils travaillent." — TR.
41 LEIBNITZ'S CRITIQUE OF LOCKE him1), but very far from denying the merit of celebrated writers, we bear witness to it, by making known in what and why we differ from their views, when we judge it necessary to prevent their authority from prevailing over reason on some important points; besides, by satisfying such excellent men, we render the truth more acceptable, and it must be supposed that it is principally for truth that they labor.
In fact, although the author of the Essay says a thousand beautiful things which I commend, our systems are very dif ferent. His has more relation to Aristotle, mine to Plato, although we both differ in many things from the doctrine of these two ancient philosophers. He is more popular, and I am compelled sometimes to be a little more acroamatic and more abstract, which is not an advantage to me, especially when writing in a living language. I think, nevertheless, that by making two persons speak, one of whom sets forth the views drawn from the Essay of this author, and the other joins thereto my observations, the parallel will be more to the liking of the reader than wholly dry remarks, the reading of which would be interrupted at every moment by the necessity of recurring to his book in order to understand mine. It will nevertheless be well still to compare sometimes our writings, and not to judge of his views except by his own work, although I have ordinarily preserved its expressions. It is true that the constraint, which another's discourse, whose thread must be followed, gives in making remarks, has prevented me from thinking to secure the charms of which the dialogue is sus ceptible; but I hope the matter will make amends for the defects of the style.
Our differences are upon subjects2 of some importance. The question is to know whether the soul in itself is entirely empty as the tablets upon which as yet nothing has been written (tabula rasa) according to Aristotle, and the author of the Essay, and whether all that is traced thereon comes solely from the senses and from experience; or whether the soul con tains originally the principles of many ideas and doctrines which external objects merely call up on occasion, as I believe 1 Erdmann and Jacques read: " que lui," which does not occur inGcrhardt's text. — TR.
2 Erdmann and Jacques read: " ohjects." — Tu.
ON HUMAN UNDERSTANDING 43 with Plato, and even with the schoolmen, and with all those who interpret in this way the passage of St. Paul (Rom. 2: 15) where he states that the law of God is written in the heart. The Stoics call these principles 1 jjrolepses, i.e. fundamental assumptions, or what is taken for granted in advance. The Mathematicians call them general notions (KOIVUI Iwotai). Mod ern philosophers give them other beautiful names, and Julius Scaliger in particular named them semina cKternitatis, also zopyra, i.e. living fires, luminous flashes, concealed within us, but which the encounter of the senses makes appear like the sparks which the blow makes spring from the steel. And the belief is not without reason, that these glitterings indicate something divine and eternal which appears especially in the necessary truths. 'Whence another question arises, whether all truths depend upon experience, i.e. upon induction and examples, or whether there are some which have still another foundation. For if some events can be foreseen prior to any proof which may have been made of them, it is manifest that we ourselves contribute something thereto. The senses, although necessary for all our actual knowledge, are not suffi cient to give it all to us, since the senses never give us anything but examples, i.e. particular or individual truths. Now all the examples which confirm a general truth, whatever their num ber, do not suffice to establish the universal necessity of that same truth, for it does not follow that what has happened will happen in the same way. For example, the Greeks and the Komans, and all the other peoples of the earth known to the ancients, have always observed that before the lapse of twenty- four hours day changes into night, and night into day. But we. would be deceived, if we believed that the same law holds good everywhere else; for since then, the contrary has been experienced in the region of Nova Zembla. And he would still be in error who believed that, in our climates at least, this is a necessary and eternal truth, which will always endure, since we must think that the earth, and the sun even, do not necessarily exist, and that there will perhaps be a time when this beautiful star, together with its whole system, will not longer exist, at least in -its present form. Whence it appears 1 For a very full nomenclature of these principles, see Hamilton's Reid, Note A., § V., Vol. II., pp. 755-770. 8th ed., Edinburgh and London, 1880. — TR, 44 LEIBNITZ'S CRITIQUE OF LOCKE that necessary truths such as are found in pure mathematics, and particularly in arithmetic and in geometry, must have principles whose proof does not depend upon examples, nor consecjuently upon the testimony of the senses, although with out the senses it would never have occurred to us to think of them. This distinction must be carefully made, and was so well understood by Euclid, that he often proved by the reason, what is sufficiently seen through experience and by sensible images../Logic also, together with metaphysics and ethics, one of whicli shapes theology and the other jurisprudence, both natural (sciences), are full of such truths, and consequently their proof can come only from internal principles which are called innate./It is true that we must not imagine that these eternal laws of the reason can be read in the soul as in an open book, as the prsetor's edict is read upon his album without diffi culty and research; but it is sufficient that they can be discov ered in us by dint of attention, for which the senses furnish occasions, and successful experience serves to confirm reason, in much the same way as proofs in arithmetic serve for the better avoidance of error in calculating when the reasoning is long. Herein, also, human knowledge differs from that of the brutes: the brutes are purely empirics and only guide themselves by examples; for, so far as we can judge of them, they never attain to the formation of necessary propositions; while men are capable of demonstrative sciences. It is also for this reason that the faculty the brutes have for making consecutions is something inferior to the reason of man. The consecutions of the brutes are merely like those of simple empirics, who claim that what has sometimes happened will happen again in a case where something strikes them as similar, without being able to judge whether the same reasons hold good. This is why it is so easy for men to entrap the brutes, and so easy for simple empii'ics to make mistakes. This is why persons who have become skilful through age and experi ence are not exempt (from error) when they depend too much upon their past experience, as has happened to many in civil and military affairs; because they do not consider sufficiently that the world changes, and that men become more skilful by finding a thousand new dexterities, while the deer and hares of the present do not become more cunning than those of the ON HUMAX UNDERSTANDING 45 past. The consecutions of the brutes are only a shadow of reasoning, i.e. are only connections of the imagination and passages from one image to another, because in a new juncture which appears similar to the preceding they expect anew that connection which they formerly met with, as if things were united in fact because their images are united in the memory. It is true that reason also counsels us to expect ordinarily to see that happen in the future which is conformed to a long past experience, but it is not on this account a necessary and infalli ble truth, and success may cease when least expected, when the reasons change which have sustained it. Therefore the wisest men do not so commit themselves to it as not to try to discover, if possible, something of the reason of this fact in order to judge when it is necessary to make exceptions. For reason is alone capable of establishing sure rules, and supply ing what is wanting to those which were not such by inserting their exceptions; and of finding at length certain connections in the force of necessary consequences, which often furnish the means of foreseeing the result without the necessity of experiencing the sense-connections of images, to which the brutes are reduced, so that that which justifies the internal principles of necessary truths also distinguishes man from the brutes.
Perhaps our clever author will not wholly differ from my view. For after having employed the whole of his first book in rejecting innate intelligence, taken in a certain sense, he nevertheless, at the beginning of the second and in the sequel, admits that ideas, which do not originate in sensation, come from reflection. Now reflection is nothing else than attention to what is in us, and the senses do not give us what we already carry with us. That being so, can it be denied that there is much that is innate in our mind, since we are innate, so to speak, in ourselves? and that there is in us: being, unity, substance, duration, change, action, perception, pleasure, and a thousand other objects of our intellectual ideas? And these objects being immediate to our understanding and always pres ent (although they cannot always be perceived by reason of our distractions and needs), what wonder that we say that these ideas with all depending upon them are innate in us? I have made use also of the comparison of a block of marble which 46 LEIBNITZ'S CRITIQUE OF LOCKE has veins, rather than of a block of marble wholly even, pr of blank tablets, i.e. of what is called among philosophers a tabula rasa. For if the soul resembled these blank tablets, truths would be in us as the figure of Hercules is in the marble, when the marble is wholly indifferent to the reception of this figure or some other. But if there were veins in the block which should indicate the figure of Hercules rather than other fig ures, this block would be more determined thereto, and Her cules would be in it as in some sense innate, although it would be needful to labor to discover these veins, to clear them by polishing, and by cutting away what prevents them from ap pearing. Thus it is that ideas and truths are for us innate, as inclinations, dispositions, habits, or natural potentialities, and not as actions; although these potentialities are always accom panied by some actions, often insensible, which correspond to them.
It seems that our clever author claims that there is nothing virtual in us, and indeed nothing of which we are not always actually conscious; but he cannot take this rigorously, other wise his opinion would be too paradoxical; since, moreover, acquired habits and the stores of our memory are not always perceived and do not even always come to our aid at need, although we often easily recall them to the mind upon some slight occasion which makes us remember them, just as we need only the beginning of a song to remember it.1 He limits his thesis also in other places, by saying that there is nothing in us of which we have not at least formerly been conscious. But besides the fact that no one can be assured by reason alone how far our past apperceptions, which we may have for gotten, may have gone, especially according to the Platonic doctrine of reminiscence which, wholly fabulous as it is, is in no respect incompatible at least in part with reason wholly pure: besides this, I say, why must we acquire all through the perception of external things, and nothing be unearthed in ourselves? Is our soul then by itself such a blank that besides the images borrowed from without, it is nothing? This is not an opinion (I am sure) that our judicious author could approve.
1 Erdmann and Jacques read: " le commencement d'une chanson pour nous faire ressouvenir du reste," i.e. the beginning of a song to remind us of the rest. — TK.
ON HUMAN UNDERSTANDING 47 And where do we find tablets that have no variety in them selves? For we never see a plane perfectly even and uniform. Why, then, could we not furnish also ourselves with something of thought from our own depths if we should dig therein? Thus I am led to believe that at bottom his opinion upon this point is not different from mine, or rather from the common view, inasmuch as he recognizes two sources of our knowledge, the Senses and Reflection.
jT'do not know whether it will be so easy to harmonize him with us and with the Cartesians, when he maintains that the mind does not always think, and particularly that it is without perception when we sleep without dreaming; and he objects 1 that since bodies can exist without motion, souls can also exist without thought. But here I make a somewhat different reply than is customary, for I hold that naturally a substance cannot exist without action, and that there is indeed never a body without movement. Experience already favors me, and you have only to consult the book of the distinguished Mr. Boyle against absolute rest, to be con vinced of it; but I believe reason favors it also, and this is one of the proofs I have for doing away with atoms.
Moreover, there are a thousand indications which make us think that there are at every moment an infinite number of perceptions in us, but without apperception and reflection, i.e. changes in the soul itself of which we are not conscious, be cause the impressions are either too slight and too great in number, or too even, so that they have nothing sufficiently distinguishing them from each other; but joined to others, they do not fail to produce their effect and to make themselves felt at least, confusedly in the mass. Thus it is that habit makes us take no notice of the motion of a mill or a waterfall when we have lived quite near it for some time. It is not that the motion does not always strike our organs, and that something no longer enters into the soul corresponding thereto, in virtue of the harmony of the soul and the body, but these impressions which are in the soul and the body, be ing destitute of the attractions of novelty, are not strong enough to attract our attention and our memory, attached to objects more engrossing. For all attention requires memory, 1 Erdmann and Jacques read: " II dit que," i.e. He says that. — TB.
48 LEIBNITZ'S CRITIQUE OF LOCKE and often when we are not admonished, so to speak, and warned to take note of some of our own present perceptions, we allow them to pass without reflection, and even without being noticed; but if any one directs our attention to them immediately after, and makes us notice, for example, some noise which was just heard, we remember it, and are conscious of having had at the time some feeling of it. Thus there were perceptions of which we were not conscious at once, con sciousness arising in this case only from the warning after some interval, however small it may be. And to judge still better of the minute perceptions which we cannot distinguish in the crowd, I am wont to make use of the example of the roar or noise of the sea which strikes one when on its shore. To understand this noise as it is made, it would be necessary to hear the parts which compose this whole, i.e. the noise of each wave, although each of these little noises makes itself known only in the confused collection of all the others, i.e. in the roar itself, and would not be noticed if the wave which makes it were alone. For it must be that we are affected a little by the motion of this wave, and that we have some per ception of each one of these noises, small as they are; other wise we would not have that of a hundred thousand waves, since a hundred thousand nothings cannot make something. One never sleeps so soundly as not to have some feeble and confused sensation, and one would never be awakened by the greatest noise in the world if he did not have some perception of its small beginning; just as one would never break a rope by the greatest effort in the world if it were not stretched and lengthened a little by smaller efforts, although the slight extension they produce is not apparent.
These minute perceptions are, then, of greater efficacy in their results than one supposes. They form I know not what, these tastes, these images of the sense-qualities, clear in the mass, but confused in the parts, these impressions which sur rounding bodies make upon us, which involve the infinite, this connection which each being has with all the rest of the uni verse. We may even say that in consequence of these minute perceptions, the present is big with the future and laden with the past, that all things conspire (o-^Trvoia iravra, as Hip pocrates said), and that in the least of substances eyes as ON HUMAN UNDERSTANDING 49 penetrating as those of God could read the whole course of the things in the universe.
Quae sint, quse fuerint, quse mox futura trahantur.1 These insensible perceptions indicate also and constitute the same individual who is characterized by the traces or expres sions whicli they conserve of preceding states of this individual, in making the connection with his present state; and they can be known by a superior mind, even if this individual himself should not be aware of them, i.e. when there would no longer be in him the express recollection of them. But they (these perceptions, I say) furnish, indeed, the means of finding again this recollec tion at need by the periodic developments which may some day happen. It is for this reason that death can be only a sleep, and cannot, indeed, continue, the perceptions ceasing merely to be sufficiently distinguished, and being reduced in the animals to a state of confusion which suspends consciousness, but which can not last always; not to speak2 here of man, who must have in this regard great privileges in order to preserve his personality. It is also by means of the insensible perceptions that this admirable pre-established harmony of the soul and the body, and indeed of all the monads or simple substances, is ex plained; 3 which supplies the place of the unmaintainable influence of one upon the others, and which in the judgment of the author of the most excellent of dictionaries exalts the grandeur of the divine perceptions beyond what has ever been conceived. After this I would add little if I should say that it is these minute perceptions which determine us in many junctures without being thought of, and which deceive the vulgar by the appearance of an indifference of equilibrium, as if we were entirely indifferent whether we turned (for ex ample) to the right or to the left. It is not needful also that I notice here, as I have done in the book itself, that they cause that uneasiness which I show to consist in something which differs from pain only as the small from the great, and which, however, often constitutes our desire and even our 1 Erdmann reads: quse mox, etc.; Jacques: quse mox ventura trahantur. Gerhardt's reading: " que " is evidently an error. — TR.
2 Erdmann and Jacques omit: "pour ne parler icy de 1'homme qui doit avoir en cela des grands privileges pour garder sa personalite'." — TR.
3 Erdmann and Jacques read " j'explique," I explain. — TR.
E 50 LEIBNITZ'S CRITIQUE OF LOCKE pleasure by giving to it an exciting flavor. It is also l the insensible parts of our sensible perceptions, which produce a relation between the perceptions of colors, heat, and other sensible qualities, and between the motions in bodies which correspond to them; while the Cartesians together with our author, penetrating as he is, conceive the perceptions which we have of these qualities as arbitrary, i.e. as if God had given them to the soul according to his good pleasure, without any regard to any essential relation between these perceptions and their objects: a view which surprises me and which appears to me little worthy of the wisdom of the Author of things, who does nothing without harmony and without reason.
In a word, the insensible perceptions are as eminently use ful in Pneumatology 2 as are the insensible corpuscles in Physics, and it is equally unreasonable to reject the one or the other under the pretext that they are out of reach of our senses. Nothing is accomplished all at once, and it is one of my great maxims, and one of the most verified, that nature makes no leaps: a maxim which I called the Law of Continuity, when I spoke of it in the first "Nouvelles de la Republique des Lettres," 3 and the use of this law is very considerable in Physics. This law declares that we pass always from the small to the great, and the reverse, through the medium, in degree as in parts, and that motion never springs immediately from rest, nor is reduced thereto save by a smaller motion, as one never completes the survey of any line or length until he has com pleted a smaller line, although hitherto those who have set forth the laws of motion have not observed this law, believing that a body can receive in a moment a motion contrary to the preceding. And all this makes one indeed think that the 1 Erdmann and Jacques read: " Ce sent les memes parties insensibles," etc., It is the same insensible parts, etc. — TR.
8 A literary journal published by Pierre Bayle at Amsterdam, 1084-1687; afterwards continued, at Bayle's request, by Basnasje, under the title " Histoire de onvrages dtss Savants," 1G87-170!). Leibnitz published in this journal in July, l(ii)8, his Eclaircissement des d/fficultes que M. Hai/le a trainees dans le systeme nouveau de I' union de I'ame et du corps. Gerhardt, Vol. 4, pp. 517- 524; Erdmann, pp. 150-154; Jacques, Vol. 1, pp. 481-487. Translation, Appen ON HUMAN UNDERSTANDING 51 noticeable perceptions also arise by degrees from those which are too minute to be observed. To think otherwise, is to have little knowledge of the immense subtilty of things which always and everywhere surrounds an actual infinite.
I have also noticed that in virtue of these insensible varia tions, two individual things cannot be perfectly alike, and that they must always differ more than numero: a fact which destroys the blank tablets of the soul, a soul without thought, a substance without action, a vacuum in space, atoms and even particles not actually divided in matter, absolute rest, entire uniformity in one portion of time, place, or matter^ perfect globes of the second element, born of cubes perfect and orig- inaL/and a thousand other fictions of philosophers which arise from their incomplete notions, and which the nature of things does not allow, and which our ignorance and the little atten tion we give to the insensible let pass, but which cannot be made tolerable unless they are limited to the abstractions of the mind which protests that it does not deny what it puts aside, and thinks should not enter into any present considera tion. Otherwise if it were very well understood, viz.: that things of which we are not conscious are neither in the soul nor the body, we should be lacking in philosophy as in politics, in neglecting TO /xi/c/adv, the insensible progressions, while an abstraction is not an error, provided we know what it is that