we feign therein. Just as the mathematicians employ it when they speak of the perfect lines which they propose to us, of uniform motions and of other regulated effects, although matter (i.e. the medley of the effects of the surrounding infinite) always makes some exception. It is for the sake of distinguishing the considerations and of reducing so far as we may do so the effects to reasons, and of foreseeing some of their consequences, that we proceed thus. For the more we are careful to neglect no consideration that we can regulate, the more practice corre sponds to theory. But it belongs only to the supreme Reason, whom nothing escapes, distinctly to comprehend all the infinite and to see all the reasons and all the consequences. All that we can do in regard to infinites is to know them confusedly, and to know at least distinctly that they are such; otherwise we judge very wrongly of the beauty and the grandeur of the universe; so also we could not have a sound Physics explaining 52 LEIBNITZ'S CRITIQUE OF LOCKE the nature of bodies in general, and still less a proper Pneuma- tology comprising the knowledge of God, of souls, and of simple substances in general.
This knowledge of insensible perceptions serves also to explain why and how two souls, human or otherwise,1 of one and the same species never come forth perfectly alike from the hands of the Creator and have always each its original relation to the points of view which it will have in the uni verse. But this it is which already follows from the remarks I have made about two individuals, viz.: that their difference is always more than numerical. There is, moreover, another point of importance, in respect to which I am obliged to devi ate not only from the opinions of our author, but also from those of the majority of modern philosophers: I believe with the majority of the ancients that all genii,2 all souls, all simple created substances, are always joined to a body, and that there are never souls entirely separated. I have a priori reasons for my view; but the doctrine will be found to have this advan tage, that it resolves all the philosophical difficulties as to the condition of souls, their perpetual conservation, their immor tality, and their operation. The difference between one of their states and another, never being and never having been other than that of more sensible to less sensible, of more perfect to less perfect, or the reverse, this doctrine renders their past or future state as explicable as that of the present. One feels sufficiently, however little reflection he makes, that this is rational, and that a leap from one state to another infinitely different could not be natural. I am astonished that by leaving the natural without reason, the schoolmen have been willing purposely to plunge themselves into very great difficulties, and to supply matter for apparent triumphs of the strong-minded, all of whose reasons fall at once by this explanation of things, in which there is no more difficulty in conceiving the conservation of souls (or rather, according to my view, of the animal) than there is in conceiving the change of the caterpillar into the butterfly, and the conservation of thought in sleep, to which Jesus Christ has divinely well com pared death. I have already said also that sleep could not 1 Erdmann reads: "on deux clioses," or two things. — TR.
2 I.e. Aiiujels and arc-ban jrels. — TR.
ON HUMAN UNDERSTANDING 53 last always, and it will last least or almost not at all in the case of rational souls who are always destined to preserve the personality which has been given them in the City of God, and consequently remembrance: and this in order to be more susceptible of chastisements and recompenses. And I add further that in general no derangement of the visible organs is capable of throwing things into entire confusion in the animal or of destroying all the organs and depriving the soul of all its organic body and of the ineffaceable remains of all preceding traces. But the ease with which the ancient doc trine of subtile bodies connected with the angels (which was confounded with the corporeality of the angels themselves) has been abandoned, and the introduction of pretended sepa rate intelligences in creatures (to which those who make the heavens of Aristotle revolve have contributed much), and finally the poorly understood view into which we have fallen, that the souls of brutes could not be preserved without falling into metempsychosis, and1 without conducting them from body to body, and the perplexity into which men have fallen by their ignorance of what to do with them, have caused us, in my opinion, to neglect the natural explanation of the conserva tion of the soul. This has done much harm to natural relig ion, and has caused many to believe that our immortality was only a miraculous grace of God, of which also our cele brated author speaks with some hesitation, as I shall presently remark. But it would be well had all those who are of this opinion spoken as wisely and in as good faith as he, for it is to be feared that many who speak of immortality as a grace do so only to keep up appearances, and resemble at bottom these Averroists and some bad Quietists who picture to themselves an absorption and the reunion of the soul with the ocean of divinity: a notion whose impossibility my system alone perhaps evinces.
It seems also that we differ further in regard to matter, in that the author thinks that a vacuum is necessary to motion, because he thinks that the minute parts of matter are rigid. And I admit that if matter were composed of such parts, 1 Gerhardt's text is: "et sans les promener de corps en corps, et 1'embar- ras ou Ton a este en ne sachant ce qu'on en devoit faire." Erdmaiin and Jacques omit the clause. — Tit.
54 LEIBNITZ'S CRITIQUE OF LOCKE motion in a plenum would be impossible, as if a room were full of a quantity of little pebbles without there being the least empty space. But this supposition, for which there appears also to be no reason, is not admissible, although this learned author goes as far as to believe that rigidity or cohe sion of the minute parts makes the essence of the body. It is necessary rather to conceive space as full of a matter origi nally fluid, susceptible of all the divisions, and even actually subject to divisions and subdivisions to infinity, but with this difference, however, that it is divisible and divided un equally iu different parts on account of the motions which more or less concur there. This it is which causes matter to have everywhere a degree of rigidity as well as of fluidity, and no body to be hard or fluid in the highest degree, i.e. no atom to be found of an insurmountable hardness nor any mass entirely indifferent to division. The order, also, of nature, and particularly the law of continuity, destroy equally the one and the other.
I have also shown that cohesion, which by itself would not be the effect of impulse or of motion, would cause a traction, taken strictly. For if there were a body originally rigid, — for example, an Epicurean atom, — which should have a part pro jecting like a hook (since we can imagine atoms of all sorts of shapes), this hook pushed would draw with it the rest of this atom; i.e. the part which is not pushed, and which does not fall in the line of the impulsion. Our learned author, how ever, is for himself opposed to these philosophic tractions, such as were formerly attributed to the abhorrence of a vacuum, and he reduces them to impulsions, maintaining with the moderns that one part of matter works immediately upon another only by pushing it by contact, in which I think they are right, because otherwise there is nothing intelligible in the operation.
I must not, however, conceal the fact that I have noticed a sort of retraction by our excellent author on this subject, whose modest sincerity I cannot forbear praising in this respect as much as I have admired on other occasions his penetrating genius. It is in his reply to the second letter of the late Bishop of Worcester,1 printed in 1699, p. 408, where, 1 Edward Stillin.u'fleet, lf>3o-l(i!)0: Bishop of Worcester, UW'J-Kiil'.). — TR.
ON HITMAN UNDERSTANDING 65 in order to justify the view which he had maintained against this wise prelate, viz.: that matter might think, he says among other things: " / admit that I said (Essay on Understanding, Book II. chap. 8, § 11) that body acts by imjndse and not otherwise. This also ivas my vieiv when I wrote it, and even now I cannot conceive its action in any other way. But since then I have been convinced by the judicious Mr. Newton's incomparable book that there is too much presumption in wishing to limit the power of God by our limited conceptions. The gravitation of matter towards matter in ivays inconceivable to me, is not only a demonstration that God, when it seems to him good, can put into bodies powers and modes of acting which are beyond what can be derived from our idea of body or explained by ivhat we know of matter; but it is furthermore an incontestable instance that he has really done so. I shall therefore take care to correct this passage in the next edition of my book." l I find that in the French version of this book, made undoubtedly from the latest edi tions, the matter has been put thus in this § 11: It is evident, at least so far as we can conceive it, that it is by impulse and not otherwise that bodies act on each other; for it is impossible for us to understand how the body can act upon ivhat it does not touch, which is the same as to imagine that it can act tvhere it is not.
I can only praise this modest piety of our celebrated author, who recognizes that God can do more than we can understand, and that thus there may be inconceivable mysteries in the articles of faith; but I should not wish to be obliged to recur to the miracle in the ordinary course of nature and to admit powers and operations absolutely inexplicable. Otherwise too much, license will be given poor philosophers, itnder cover of what God can do, and by admitting these centripetal virtues or these immediate attractions from afar without being able to make them intelligible, I see nothing to hinder our Scholastics from saying that everything is done simply by their faculties and from maintaining their intentional species which proceed 1 I have retranslated the passage from the French version, as given by Ger- hardt. For the original, cf. Locke, Philos. Works (Bonn's ed.), Vol. II., p. 395. The entire letter is found in Locke's Works, Vol. I., pp. 578-774; this particu lar passage, p. 754. Edition of 4 vols., 4to. 7th ed., 1708. Printed for H. Wood- fall, A. Millar, and others. — TR.
56 LEIBNITZ'S CRITIQUE OF LOCKE from objects even to us and find means of entering even into our souls. If that is so, Omnia jam fient, fieri quse posse negabam.
So that it seems to me that our author, quite judicious as he is, goes here a little too much from one extreme to the other. He makes a difficulty in regard to the operations of souls when the question is only of admitting what is not sensible, and behold he gives to bodies what is not even intelligible; granting them powers and actions which surpass in my view all that a created spirit can do and understand, since he grants them attraction, and that even at great distances without limiting them to any sphere of activity, and this in order to maintain a view which does not appear less inexplicable, viz.: the possi bility of the thought of matter in the natural order.
The question which he discusses with the celebrated Prelate who attacked him, is, whether matter can think, and as it is an important point even for the present work, I cannot refrain from entering upon it a little and from taking note of their controversy. I will give the substance of their discussion upon this subject, and take the liberty of saying what I think of it. The late Bishop of Worcester, fearing (but in my opinion without good reason) lest our author's doctrine of ideas might be liable to certain abuses prejudicial to the Christian faith, undertook to examine some points in it in his "Vindication of the Doctrine of the Trinity "; * and having rendered justice to this excellent writer, by recognizing that he thinks the exist ence of spirit as certain as that of body, although one of these substances is as little known as the other, he asks (p. 241 sq.) how reflection can assure us of the existence of spirit, if God can give to matter the power of thought according to the view of our author, Book IV., chap. 3, since thus the way of ideas which must serve to discern 2 what may suit the soul or the body, would become useless; while he had said in Book II. of the Essay on Understanding, chap. 23, §§ 15, 27, 28, that the operations of the soul furnish us the idea of mind and the 1 Published in the autumn of 1090. Cf. Alexander Campbell Fraser, Locke, pp. 245-240 (Philosophical Classics), Edinburgh: Wm. Black-wood and Sons, 2 Gerhardt reads: " disoerner "; Erdmanii and Jacques: " discuter," to discuss, debate, argue. — TK.
ON HUMAN UNDERSTANDING 57 understanding, and the will renders this idea as intelligible to usjis_the nature of body is rendered intelligible to us by solid ity and impulse. This is how our author replies in his first letter (p. 65 sq.): " I believe I have proved that there is a spirit ual substance in us, for we experience in ourselves thought. Now this action or this mode cannot be the object of the idea of a thing subsisting by itself, and consequently this mode needs a support, a subject, in which it may inhere, and the idea of this support forms what we, call substance...For since the general idea of sub stance is everywhere the same, it, follows that the modification, ichich is called thought or power of thinking, being joined to it, there results a mind without the necessity of considering ivhat other modification it has besides; i.e. ichether it has solidity or not. And, on the other hand, the substance which has the modifi cation called solidity will be matter, whether thought is joined to it or not. But if by a spiritual substance you mean an immaterial substance, I admit that I have not proved that there is one in us, and that it cannot be demonstrably proved on my principles. Al though ivhat I have said on the systems of matter (Book IV., chap. 10, § 16) in proving that God is immaterial, renders it in the highest degree probable, that the substance ivhich thinks in us is immaterial...However, I have shown [the author adds, p. 68] that the great ends of religion and of morals are assured by the immortality of the soul, without the need of supposing its immateriality." 1 The learned Bishop in his reply to this letter, in order to make it evident that our author held another view, when he wrote the second book of the Essay, quotes, p. 51, this passage (taken from the same book, chap. 23, § 15), where it is said, that by the simple ideas ivhich we have deduced from the operations of our mind, we can form the complex idea of a mind. And that putting together the ideas of thought, of perception, of liberty, and of power to move our body, we have as clear a notion of immate rial substances as of material. He quotes still other passages to show that the author opposes mind to body. And he says (p. 54) that the ends of religion and of morals are the better 1 1 have retranslated the passage from the French version as given by Ger- hardt. For the original, cf. Locke, Philos. Works (Bohn's ed.), Vol. II., p. 387. The entire letter is found in Locke's Works, Vol. I., pp. 458-517; this particular passage, p. 477. Edition of 4 vols., 4to. 7th ed., 1768. Printed for H. Woodfall, A. Millar, and others. — TK.
58 LEIBNITZ'S CRITIQUE OF LOCKE assured by proving that the soul is immortal by its nature, i.e. immaterial. He quotes also (p. 70) this passage, that the ideas we have of particular and distinct kinds of substances are nothing else than different combinations of simple ideas;1 and that thus the author believed that the idea of thinking and of willing gave another substance different from that which the idea of solidity and of impulse gives, and that (§ 17) he remarks that these ideas constitute the body as opposed to mind.
The Bishop of Worcester might add that from the fact that the general idea of substance is in the body and in the mind, it does not follow that their differences are modifications of one and the same thing, as our author has just said in the part of his first letter which I have quoted. It is necessary carefully to distinguish between modifications and attributes. The faculties of having perception and of acting, extension, solid ity, are attributes or perpetual and principal predicates; but thought, impetuosity, figures, movements, are modifications of these attributes. Furthermore, we must distinguish between physical (or, rather, real) genus and logical or ideal genus. Things which are of the same physical genus, or which are homogeneous, are of the same matter, so to speak, and may often be changed the one into the other by the change of mod ification, as circles and squares. But two heterogeneous things may have a common logical genus, and then their differences are not simple accidental modifications of one and the same subject, or of one and the same metaphysical or physical mat ter. Thus time and space are very heterogeneous things, and we should do wrong to imagine I know not what real common subject which had only the continuous quantity in general, and whose modifications should cause the rise of time and space.2 S'ome one will perhaps laugh at these distinctions of the philosophers of two genera, the one merely logical, the other real; and of two matters, the one physical, viz.: that of bodies, the other metaphysical only or general; as if some one said that two parts of space are of one and the same matter, or that two hours are likewise among themselves of one and 1 Locke, Philos. Works (Bohn's ed.), Vol. 1, p. 426, chap. 23, § fi. — TR.
2 Erdmann and Jacques add: " Cependant leur genre logique commun est la quantite continue," i.e. Nevertheless their common logical genus is the con tinuous quantity. — TR.
ON HUMAN UNDERSTANDING 59 the same matter. Nevertheless, these distinctions are not dis tinctions of terms merely, but of things themselves, and seem to come in here very opportunely, where their confusion has given rise to a false conclusion. These two genera have a common notion, and that of the real genus is common to the two matters, so that their genealogy will be as follows: — ( Logical merely, varied by simple differences.
( Metaphysical only, where 1 Real, whose differences are modi- I there is homogeneity. [ fications, i.e. Matter. 1 Physical, where there is a solid homogeneous mass.
I have not seen the second letter of the author to the Bishop, and the reply which this prelate makes to it scarcely touches the point relating to the thinking of matter. But the reply of our author to this second answer returns to it. God (says he, nearly in these words, p. 397) adds to the essence of matter the qualities and perfections tchich please him, simple movement in some parts, but in plants, vegetation, and in ani mals, sentiency. Those who agree up to this point, cry out as soon as we go a step farther, and say that God can give to matter thought, reason, will, as if this destroyed the essence of matter. But to prove it, they allege that thought or reason is not included in the essence of matter, a point of no consequence, since move ment and life are not included therein either. They assert, also, that we cannot conceive of matter as thinking; but our conception is not the measure of God's power.1 After this he cites the ex ample of the attraction of matter (p. 99, but especially p. 408), where he speaks of the gravitation of matter towards matter, attributed to Mr. Newton (in the terms which I have quoted above), admitting that we can never conceive the manner of it. This is in reality to return to the occult, or, what is more, in explicable qualities. He adds (p. 401) that nothing is more calculated to favor the sceptics than to deny what we do not understand; and (p. 402) that we do not conceive even how the soul thinks. He will have it (p. 403) that, since the two sub- 1 For the original, cf. Locke, Philos. Works (Bohn's od.), Vol. 2, pp. 390, 391. The entire letter is found in Locke's Works, Vol.1, pp. 578-774; this particu lar passage, pp. 749, 750. Edition of 4 vols., 4to. 7th ed., 1768. Printed for H. Woodfall, A. Miller, and others. — TR.
60 LEIBNITZ'S CRITIQUE OF LOCKE stances, material and immaterial, are capable of being conceived in their naked essence without any activity, it depends upon God to give to each the power of thought. And he wishes to take advantage of the admission of his opponent, who had granted sentiency to the brutes, but who would not grant them any immaterial substance. He claims that liberty, conscious ness (p. 408), and the power of abstract thought (p. 409) can be bestowed upon matter, not as matter, but as enriched by a divine power. Finally, he quotes (p. 434) the remark of a traveller as eminent and judicious as M. de la Loubere,1 that the pagans of the East acknowledge the immortality of the soul without being able to comprehend its immateriality. --On all this I would remark, before coming to the explana tion of my view, that it is certain that matter is as little capa ble of mechanically producing feeling, as of producing reason, as our author admits; that in truth I acknowledge that it is not permissible to deny what we do not understand, but I add that we are right in denying (at least in the natural order) what is absolutely neither intelligible nor explicable. I main tain, also, that substances (material or immaterial) cannot be conceived in their naked essence without any activity; that activity belongs to the essence of substance in general; that, finally, the conception of creatures is not the measure of God's power, but that their conceptivity, or power of conception, is the measure of nature's power; all this is in harmony with the natural order, being capable of being conceived or under stood by some creature.