make vise of them constantly without citing them; so that we should be mistaken in thinking that they are not there, because we do not perhaps always see them quoted in the margin.
474 LEIBNITZ'S CRITIQUE OF LOCKE [BK. iv Ph. But he objects to the example from theology. For the knowledge of this holy religion came to us from revelation (says our author), and without this aid the maxims would never have been able to make us know it. The light comes to us then from the things themselves, or immediately from the infallible veracity of God.
Th. It is as if I said, medicine is based upon experience, reason then is of no use therein. Christian theology, which is the true medicine for souls, is based upon revelation which corresponds to experience; but to make of it a perfect body, we must unite therewith natural theology, which is drawn from the axioms of eternal reason. Is not this principle indeed that veracity is an attribute of God, upon which you acknowledge that the certainty of revelation is based, a maxim taken from natural theology?1 Ph. Our author wishes to distinguish between the means of acquiring knowledge and of teaching it, or rather between teaching and communicating. After schools had been erected and professors established to teach the sciences that others had found out, these professors availed themselves of these max ims in order to impress the sciences upon the minds of their scholars, and to convince them by means of the axioms of cer tain particular truths; while the particular truths have served the first discoverers in finding the truth without the general maxims.
Th. I wish that this pretended procedure had been justified for us by examples of some particular truths. But rightly considering things, we shall not find it practised in the estab lishment of the sciences. And if the discoverer finds only a particular truth, he is only half a discoverer. If Pythagoras 2 1 Locke, without discussing its possibility or its method, assumes a special source of religion in an immediate revelation of God to the soul of man, and rests the truth of this revelation upon the " unerring veracity " of God. Cf. Philos. Wks., Vol. 2, p. 209, Bohn's ed. Leibnitz, who elsewhere discusses to a certain extent both the possibility and the method of revelation, and admits its possibility, and also its actuality, especially as regards those things which are beyond the limits of our finite experience, emphasizes the rational element in theology by calling attention to the fact that revelation presupposes a nat ural idea of God, philosophically derived and including the attribute of verac ity, to which it may appeal and by which its character and claims to authority must be judged. — TR.
2 Cf. ante, p. 379, note 1. On his life and philosophy, cf. Zeller, Philos. d. Griech., 5th ed., Vol. 1, pp. 296 sq. For his mathematical work, cf. G. J.
CH. vii] ON HUMAN UNDERSTANDING 475 had only observed that the triangle whose sides are 3, 4, 5, has the property of the equality of the square on the hypothenuse with those on the sides (i.e. that 9 + 16 = 25), would he on that account have been the discoverer of this great truth which includes all right-angled triangles, and which has passed into a maxim with the geometers? It is true that often an exam ple, seen by chance, serves as the occasion which suggests to a clever man the search for general truth, but it is still very often no easy matter to find it; besides, this path of discovery is not the best nor the most employed by those who proceed in an orderly and methodical way, and they make use of it only upon the occasions when better methods fall short. In the same way, some have thought that Archimedes found the quadrature of the parabola by weighing a piece of wood cut parabolically, and that this particular experiment caused him to discover the general truth; but those who know the pene tration of this great man see clearly that he had no need of such an aid. Moreover, if this empirical way of particular truths had been the occasion of all the discoveries, it would not have been sufficient to give them; and the discoverers themselves have been delighted with observing the maxims and the general truths if they have been able to attain them, otherwise their discoveries would have been very imperfect. All that may then be attributed to the schools and to the pro fessors, is that they have collected and arranged the maxims and other general truths: and would God they had done so still more and with more care and choice, the sciences would not be found so scattered and so confused. For the rest I admit, that there is often some difference between the method we use in teaching the sciences and that which has produced their discovery: but this is not the point in question. Some times, as I have already observed, chance has given occasion for discovery. If we had noticed these occasions, and had preserved the memory of them for posterity (which would have been very useful), this detail would have been a very con siderable part of the history of the arts, but it would not have Allman, Greek Geometry from Thalcs to Euclid, Dublin, 1889, and, by the same author, Pythagorean Geometry, being the mathematical part of the article "Pythagoras" in the Encydop. Brit., 9th ed., Vol. 20, pp. 14CJ-149 476 LEIBNITZ'S CEITIQUE OF LOCKE [UK. iv been proper to make systems of them. Sometimes also dis coverers liave proceeded rationally to the truth, but by ex tended circuits. I find that in matters of importance authors would have rendered service to the public, if they had been willing sincerely to indicate in their writings the traces of their experiments; but if the system of science should be built upon that foundation, it would be as if in a finished house you wished to preserve all the apparatus which1 the architect re quired in building it. Good methods of teaching are all such that by their means science could certainly have been discov ered; and then if they are not empirical, i.e. if the truths are taught by reasons or by proofs draAvn from ideas, it will always be by axioms, theorems, canons, and such other general propo sitions. The case is different when the truths are aphorisms like those of Hippocrates,2 i.e. truths of fact either general, or 1 Gerhardt reads " done," manifestly a manuscript or a typographical error. Erdmann, Jacques, and Janet read "dont," which the translation follows. — TR.
2 Hippocrates of Cos, 460-375 B.C., the " Father of Medicine," was the first to hase the practice of medicine on the observation of nature and the principles of an inductive philosophy. Though descended from a family of priest-physi cians, he put aside all its traditions and prejudices, gave himself up to the study of the natural history of disease in the living suhject, and treated it always as subject to natural laws. He placed especial emphasis on sympto- mology and dieteties. The two chief modern critical editions of his writings, or those ascrihed to him, are E. Littrc, (Euvres completes d'Hippocrate, 10 vols., Paris, 1839-61, and F. Z. Ermerins, Hippocratis et aliorum medicorum veterum reliquiae, 3 vols., Utrecht, 1859-64. The 'A<^opi<r/u.oi — Aphorisms — are accepted as absolutely genuine by Littre, but rejected as spurious by Ermerins. The Greek text with French trans, is found in Littre, op. cit., Vol. 4, pp. 396 sq.; with Latin trans., in Ermerins, op. cit., Vol. 1, pp. 397 sq. For an English translation, c,f. F. Adams, Genuine Wks. of Hippocrates (Sydenham Soc.),2 vols., London, 1849, Vol. 2, p. 685.
In this connection I may add that Professor Schaarschmidt of Bonn Uni versity has kindly informed me that the phrase a-v^Trvot-a navra cited by Leibnitz from Hippocrates, cf. ante, p. 48 (ad fin.) is to be found in the iiepi. Tpo</>rjs, § 23, Littre, (Euvres d'Hif>pocratc,~Vol. 9, p. 106, where it runs thus: Euppota /j.ia, f u/uTri'oia nia, fu/oi7ra0e'a ndi'Ta • K.r.A. Professor Schaarschmidt thinks that Leib nitz probably read: f v^-nvoia. iravra, — conspirantia omnia, — omitting pia and gvniradfa, and took gvfjL-n-voia for an adjective, while it is in the text a substan tive meaning concordance, — conspiratio, — a usage which sometimes occurs, cf. Stephanus, Thesau. Ling. Grsec., Vol. 3, p. 416, C; or that he quoted from memory, as he often does. SVH-TT^OVS — conspirans — as an epithet of the universe occurs in Plutarch, De fato, 2, 574, E: TO $u<rei SioiKfivdai -rovSe TOV KOUIJ.OV, crvunvovv, Koi cro/uiTraer), avrov CLVT<? ovra, i.e. " that the World is governed by Nature, and that it conspires, consents, and is compatible with itself." Plutarch's Morals, Eng. trans., by several hands, corrected and revised by W. W. Goodwin, Ph.D., Vol. 5, p. 308, Boston: Little, Brown & Co., 1870. — Tu, CH. vn] ON HUMAN UNDERSTANDING 477 at least true most frequently, learned by observation or based on experience, and for which there are no reasons immedi ately convincing. But the question here is not about this, for these truths are not known by the connection of ideas.
Ph. Here is the manner in which our ingenious author con ceives that the need of maxims has been introduced. The schools having established disputation as the touchstone of the ability of people, they adjudged the victory to the one who holds the field of battle and speaks the last word. But in order to furnish means of convincing the obstinate, it was necessary to establish maxims.
Th. The schools of philosophy had done better, no doubt, to unite practice with theory, as do the schools of medicine, chemistry, and mathematics; and to give the prize to the one who had done the best, especially in ethics, rather than to the one who had spoken the best. Yet as there are matters in which discourse itself is an effect and sometimes the sole effect and masterpiece which can make known the ability of a man, as in metaphysical matters, we have had reason on some occasions to jiidge of the ability of people by their suc cess in the conferences. We know, indeed, that at the begin ning of the Reformation the Protestants challenged their adversaries to come to colloquies and discussions, and some times upon the success of these discussions the public con cluded for the reform. We know, also, how much the art of speaking and of giving birth and force to reasons, and, if it may be so called, the art of discussion, can accomplish in a council of state and of war, a court of justice, a medical con sultation, and even in a conversation. And we are obliged to recur to this means and to content ourselves with words instead of acts on those occasions, for this very reason that the question then concerns an event or future fact where it would be too late to learn the truth by the effect. Thus the art of discussion or of contending by reasons (whereby I here understand the quotation of authorities and examples) is very great and very important; but unfortunately it is very badly managed, and for this reason also often reaches no conclusion or a bad one. It is for this reason that I have more than once intended to remark upon the colloquies of theologians, accounts of whom we have, in order to show the defects which 478 LEIBNITZ'S CRITIQUE OF LOCKE [UK. iv may be noticed in them and the remedies that might be em ployed therefor. In consultations upon business, if those who have the most power have not a very solid mind, authority or eloquence prevail ordinarily, although they are banded against the truth. In a word, the art of conferring and discussing would need to be entirely remodelled. As for the advantage of the one who has the last word, it is almost wholly in free conversations; for in councils suffrages or votes go by order, whether they begin or finish with the last in rank. It is true that it ordinarily belongs to the president to begin and end, i.e. to propose and decide; but he decides according to the plurality of the votes. In academic discussions it is the respondent or maintainant (of the thesis) who speaks last, and the field of battle abides with him, almost always by an established custom. It is a question of testing him, not of confounding him; otherwise it would be treating him as an enemy. In reality, there is almost no question of truth on these occasions: indeed, opposite theses are maintained at different times in the same chair. The hall of the Sorbonne was shown to Casaubon,1 and they said to him: this is the place where they have disputed for so many centuries; he replied, to what conclusion have they come?
Ph. The wish was, however, to prevent the dispute from going on to infinity, and to furnish means of deciding between two equally expert combatants, in order that the dispute enter not upon an infinite series of syllogisms. This means was the introduction of certain general propositions, the larger part self-evident, and which being of such a nature as to be received by all men with entire consent, were to be regarded as general measures of truth, and to hold the place of principles (when the disputants had posited no others), beyond which none could go, and to which both sides were obliged to hold. Thus these maxims having received the name of prin ciples which could be denied in the dispute, and which ended the question, they were taken erroneously (according to my author) as the sources of knowledge and the foundations of the sciences.
1 Isaac Casaubon, 1559-1614, a great classical scholar and editor, who had the reputation of being, next to Scaliger, the most learned man of his age. Leibnitz also relates this anecdote in his letter to Thomas Burnett, Feb. 1-11, 1(597, Gerhardt, 3, 192, Dutens, 6, 245.— TR.
en. vn] ON HUMAN UNDERSTANDING 479 Th. Would to God we had made use of them in this way in the discussions, there would be nothing to say in reply, for we should decide something. And what better thing could we do than to reduce controversy, i.e. contested truths to truths evident and incontestable? would not that be to estab lish them in a demonstrative fashion? And who can doubt that these principles, which would end disputes by establish ing truth, would not be at the same time sources of knowledge? For, provided the reasoning is good, it matters not whether it is carried on silently in one's study, or exposed for sale publicly in a professor's chair. And even if these principles were assumptions rather than axioms, taking the assumptions not as Euclid, but as Aristotle, i.e. as suppositions which must be admitted while waiting opportunity to prove them, these principles would always have this use, that by means of them all the other questions would be reduced to a small number of propositions. Thus I am the most surprised of anybody to see a praiseworthy thing blamed by I know not what prepossession, to which we clearly see by the example of your author the most clever men are susceptible through want of attention. Unfortunately they do an entirely differ ent thing in academic disputes. Instead of establishing gen eral axioms, they do all they can to weaken them by vain and little understood distinctions, and it pleases them to employ certain philosophical rules, of which there are large books completely full, but which are little certain and little deter mined and which they have the pleasure of eluding while dis tinguishing them. This is not the way to end the disputes, but to render them infinite, and finally to wear out the adversary. It is as if we put him in a dark place, where we strike at random and no one can judge the blows. This invention is admirable for the maintainants (Respondentes) who are engaged in maintaining certain theses. It is a buck ler of Vulcan which renders them invulnerable; it is Orci galea, Pluto's helmet, which renders them invisible. They must be very unskilful or very unfortunate if they can be caught with that. It is true there are some rules which have exceptions, especially in questions into which many circum stances enter, as in jurisprudence. But to render their use sure these exceptions must be determined in number and 480 LEIBNITZ'S CRITIQUE OF LOCKE [BK. iv sense so far as possible; and then it may be that the excep tion itself has its sub-exceptions, i.e. its replications, and that the replication has its duplications, etc., but at the end of the reckoning, all these exceptions and sub-exceptions, clearly de termined, and joined with the rule, must achieve universality. Of this jurisprudence furnishes very remarkable examples. But if these kinds of rules, loaded with exceptions and sub- exceptions, should enter into academic disputes, it would always be necessary to dispute pen in hand, holding as a protocol what is said by both sides. And this would be more necessary elsewhere, in disputing constantly pro forma by means of many syllogisms, mixed from time to time with dis tinctions, which the best memory in the world must confound. But we are not kept from giving ourselves this trouble, from pushing sufficiently the formal syllogisms and from registering them, in order to discover the truth when it is without recom pense, and we should not indeed succeed therein, if we wished, unless the distinctions are excluded or better regulated.
Ph. It is, however, true, as our author observes, that the scholastic method having been introduced also into conversa tions outside the schools, in order to shut the mouths of cavillers, has produced a bad effect. For, provided we have mediate ideas, we may have the connection without the aid of the maxims and before they have been produced, and that would be sufficient for sincere and tractable people. But the method of the schools having authorized and encouraged men in opposing and resisting evident truths until they are reduced to contradict themselves or to fight established principles, it is no wonder that in ordinary conversation they are not ashamed to do what in the schools is a subject of glory and counted a virtue. The author adds that reasonable people, among the rest of the world, who are not yet corrupted by education, will find it very difficult to believe that such a method has ever been followed by persons who make a pro fession of loving truth, and who pass their lives in studying religion or nature. I shall not inquire here (says he) how this method of instructing is fitted to turn away the minds of young people from the love of and sincere search for the truth, or rather to make them doubt if there really is any truth in the world, or at least any which deserves their CH. vii] ON HUMAN UNDERSTANDING 481 adherence. But what I strongly think (he adds) is this, that excepting those places which have admitted the Peripatetic philosophy into their schools, where it has reigned many cen turies without teaching the world anything but the art of dis putation, these maxims are nowhere regarded as the foundations of the sciences nor as important aids to advancement in the knowledge of things.
Th. Your clever author will have it that the schools alone have been led to form maxims; but it is the general and very rational instinct of the human race. You can infer this from the proverbs which are in use among all nations, and which are usually only maxims which the public acknowledge. But when persons of judgment make a statement which appears to us contrary to the truth, we must do them the justice to sus pect that there is a greater defect in their expressions than in their sentiments: a procedure confirmed here in our author, of whose motive animating him against the maxims, I begin to catch a glimpse. Cavilling, as well as the desire to be con vinced in order to yield, exists as really in ordinary discourse, where there is no question of exercise, as in the schools; else where most frequently they have the better grace to suppress the majors which are understood, and to be contented with enthymemes, and indeed without forming premises it is suffi cient often to use the simple medius terminus or mediate idea, the mind understanding sufficiently its connection without ex pressing it.1 And this is satisfactory when this bond is incon testable; but you, sir, will also agree with me that often we go too fast in assumption, and that paralogisms arise so that it would very often be better to have regard for certainty, in expressing ourselves, than to prefer thereto brevity and elegance. But the prejudice of your author against maxims 1 Ordinarily in argumentation we omit one of the premises, usually the major, as easily understood and too clearly manifest to require statement. Sometimes, but less commonly, we omit the minor premise, and occasionally the conclusion, as in epigrams and other forms of wit, the whole point of which very often consists in making apparent the unexpressed truth. Leib nitz emphasizes the sufficiency of the middle term — medius terminus — or mediate idea, because through it, the common term in the premises expressing the particular reason in the given case, the conclusion is reached, whence the middle term is sometimes called the argument. The mind having grasped the particular reason expressed in this term, can easily supply the rest of the argu ment, and, if necessary, state it in due syllogistic form. — TR.
482 LEIBNITZ'S CRITIQUE OF LOCKE [me. iv made him reject altogether their utility for the establishment of the truth, and goes as far as to make them accomplices with disorders in conversation. It is true that young people accustomed to academic exercises in which they are occupied a little too much with exercise and not enough in drawing from the exercise the greatest fruit it should have, viz.: knowledge, have some difficulty in emancipating themselves therefrom in the world. And one of their cavillings is not to wish to yield themselves to the truth save when it has been rendered entirely palpable to them, though sincerity and indeed civility should compel them not to wait for these ex tremes, which make them disagreeable and give a bad opinion of them. It must also be admitted that it is a vice with which men of letters are often found infected. But the fault is not in wishing to reduce truths to maxims, but in wishing to do it unseasonably and needlessly, for the human mind sees much at a glance, and it is to restrain it that we wish to compel it to stop at every step it takes and to express all that it thinks. It is precisely as if when making his account with a merchant or host one should compel him to reckon the whole with the ringers in order to be more certain of it. And to make that demand he must be either stupid or capricious. In fact, sometimes we find that Petronius had reason for saying adolescentes in scholis stultissimos fieri,1 that young people sometimes become stupid and even harebrained in places, which ought to be schools of wisdom; cornqitio o})timi pessima.'2 But still oftener they become vain, blundering, and confused, whimsical, troublesome, and that often depends on the dis position of their masters. For the rest, I find that there are far greater faults in conversation than that of demanding too much clearness. For usually we fall into the opposite vice and neither give nor ask for enough of it. If the one is troublesome, the other is hurtful and dangerous.
1 Petronius, Satyricon, chap. 1: " Et ideo ego adolescentulos existimo in sc.holis stultissimos fieri, quia nihil ex iis, qute in usu lial>emus, aut audiunt, aut vident," etc. — TR.
2 The phrase is not found in any classical author. It was perhaps suggested [TroAireias] TrapexBatri-v elvat x"Pl«''T')>', thus translated by Jowett, The Politics of Aristotle, Vol. 1, p. 109, Oxford: Clarendon Press, 1885: " That which is the perversion of the first and most divine [government] is necessarily the worst."
on. vn] ON HUMAN UNDERSTANDING 483 § 12. Ph. The use of maxims is sometimes also, when attached to false notions, vague and uncertain; for then the maxims serve to confirm us in our errors, and even to prove contradictions. For example, he who with Descartes l forms an idea of what he calls body, as of a thing which is nothing but extension, may demonstrate easily by this maxim ivhat is, is, that there is no vacuum, i.e. space without body. For he knows his own idea, he knows that it is what it is and not another idea; thus extension, body, and space being with him three words signifying one and the same thing, it is also as true for him to say, that space is body, as to say that body is body. §!'_>. But another for whom body signifies a solid extension, will conclude in the same way that to say: that space is not a body is as certain as any proposition we can prove by this maxim: it is impossible for a thing to be and not to be at the same time.