Sci. Rev. Reader ('02/05/04) 12-P5_Leibniz

Transcription

1 *Preliminary draft for student use only. Not for citation or circulation without permission of editor. 12-P5) W.G. Lebniz, "Against Barbaric Physics: Toward a Philosophy of What There Actually Is and Against the Revival of the Qualities of the Scholastics and Chimerical Intelligences" (171O 16?) 1 It is, unfortunately, our destiny that, because of a certain aversion toward light, people love to be returned to darkness. 2 We see this today, where the great ease for acquiring learning has brought forth contempt for the doctrines taught, and an abundance of truths of the highest clarity has led to a love for difficult nonsense. Clever people have such a lust for variety that, in the midst of an abundance of fruits, it seems they want to revert to acorns. That physics which explains everything in the nature of body through number, measure, weight, or size, shape and motion, which teaches that nothing is moved naturally except through contact and motion, and so teaches that, in physics, everything happens mechanically, that is, intelligibly, this physics seems excessively clear and easy. We must return to chimeras, to Archae, to certain plastic intelligences that attend to the formation of the fetus, and afterwards, to the care of the animal [... ] Some people [... ] teach that these spirits can be summoned with magic words, as a certain monk, seeking the philosopher s stone summoned the Spirit of Mercury. They would do well to recognize a more divine mechanism in the body of animals. But they believe that nothing is quite divine enough unless it is opposed to reason, and they think that what happens in [animate] bodies is so elevated that not even divine skill could make such machines. These barely skilled judges think that 1 Leibniz, W.G. Against Barbaric Physics ( ?), Philosophical Essays, Roger Ariew & Daniel Garber, eds. & trans. Indianapolis: Hackett Publishing Company, Inc., Pp

2 divine works are necessary, and so they think that God everywhere uses little vicedeities (lest God himself always have to act miraculously), just like those who once attributed the motions of the stars to their own special intelligences. It pleases others to return to occult qualities or to Scholastic faculties, but since those crude philosophers and physicians [see that] those [terms are] in bad repute, changing the name, they call them forces. But true corporeal forces are only of one kind, namely, those arising through the impression of impetus (as for example, when a body is flung forward), which even have a role to play in insensible motions. But these persons imagine specific forces, and vary them as the need arises. They bring forth attractive, retentive, repulsive, directive, expansive, and contractive faculties. This can be forgiven in Gilbert and Cabaeus, and even quite recently in Honoratus Fabri 3, since the clear foundation [ratio] for philosophizing either had not yet become known, or had not yet been sufficiently appreciated. But what person of understanding would now bring forward these chimerical qualities, which have been repeatedly offered up as the ultimate principles of things? It is permissible to recognize magnetic, elastic, and other sorts of forces, but only insofar as we understand that they are not primitive or incapable of being explained, but arise from motions and shapes. However, the new patrons of such things don t want this. It has been observed in our own times that there is a truth in the suggestion of earlier thinkers who maintained that the planets gravitate and tend toward one another. It pleased them to make the immediate inference that all matter essentially has a God-given and inherent attractive power and, as it were, mutual love, as if matter had senses, or as if a certain intelligence were given to each part of matter by whose means each part could perceive and desire even the most remote thing. [They argue] as if there were no room for mechanical explanations by which the effort gross bodies make in striving toward the great bodies of the cosmos could be accounted for through the motion of smaller pervading bodies. These same people 2 Allusion to Plato s Allegory of the Cave 3 Ref. to Gilber, explain who Cabeus and Fabri were. 2

3 threaten to give us other occult qualities of this sort, and thus, in the end, they may lead us back to the kingdom of darkness. 4 First the ancients, and on their example, many more recent people have rightly used intermediate principles for explaining the nature of things, principles that are, indeed, insufficiently explained, but principles which could be explained and which we could hope to reduce to prior and simpler principles, and, in the end, to first principles. I think that this is praiseworthy as long as composite things are reduced to simpler things. For in nature, things must proceed by steps, and one cannot go immediately to the first causes. Therefore, those who have shown that the astronomical laws can be explained by assuming the mutual gravitation of the planets have done something very worthwhile, even if they may not have given the reason for this gravitation. But if certain people, abusing this beautiful discovery, think that the explanation [ratio] given is so satisfactory that there is nothing left to explain, and if they think that gravity is a thing essential to matter, then they slip back into barbarism in physics and into the occult qualities of the Scholastics. They even fabricate what they cannot prove through the phenomena, for so far, except for the force by which sensible bodies move toward the center of the earth, they have not been able to bring forward any trace of the general attraction of matter in our region. Consequently, we must be careful not to proceed from a few instances to everything, as Gilbert sees a magnet everywhere, and the chemists smell salt, sulphur, and mercury everywhere. Such explanations are usually considered insufficient, and sometimes we derive not only things of uncertain existence from assuming such explanations, but also false and impossible things, like that general striving of matter for matter. Now physicists have taken either things or qualities as causes. Some have assumed things as elements, like Thales water, or Heracitus fire, others, the four elements, fire, air, water, and earth. [... ] Aristotle seems to have added to this a fifth 4 In making these accusations, Leibniz s principal target is Newton and his theory of universal gravitation. 3

4 stellar element. Later, the older chemists brought forward sulphur and mercury, and the more recent chemists brought forward salt, sulphur and mercury, and added the passive matters phlegm and terre damnata to these primary active matters. Boyle examined these in his Sceptical Chemist. The most recent chemists have introduced alkali and acid as active things. [... ] Also, there is no lack of people who have advocated certain incorporeal substances operating in bodies, like the Soul of the World [Anima Mundi], or like particular souls that belong to each and every thing. Similar are those who attributed sense to everything. [...] The ancients had already spoken of a certain wise Nature, acting for ends, doing nothing in vain, something worthy of praise if it is understood as applying to God or to some artifice God placed in things from the beginning, but otherwise empty. Certain persons place in things various Archae, like so many souls or spirits, indeed, like little gods, wonderfully intelligent plastic substances, which order and regulate organic bodies. And finally, there were those who summoned God or gods ex machina in the way that the pagans imagined that Jupiter rains or thunders and that he has filled the woods and waters with gods or near gods. Certain ancient Christians, and in our age, Fludd, author of the Mosaic Philosophy (elegantly refuted by Gassendi), and more recently the authors and advocates of the system of occasional causes, all believed that God acts immediately on natural things through perpetual miracle. These people, indeed, have used substances as causes. But some people have added qualities which they have also called faculties, virtues, and most recently, forces. Such were the sympathy or antipathy, or strife and friendship of Empedocles; such were heat, cold, moistness, and dryness, the four primary qualities of the Peripatetics and followers of Galen; such were the sensible and intentional species of the Scholastics, and also the expulsive, retentive, and change-causing faculties of the physicians who taught in barbaric times. 5 [... ]. Most recently in England, some have tried to bring back attractive and repulsive forces, about which we shall soon have more to say. [... ] 5 Refs. to passages in Aristotle, Galen, 4

5 Some of these people can be excused, indeed, they ought to be praised, since they tried to explain more composite things through certain simpler bodies or qualities. Thus many things have been explained, and not badly, through fire, air, water, and earth, and then through salts soluble in water, oils or sulphurs soluble in fire, and finally through limes or earth, that persist in fire, and spirits or waters that evaporate in fire. Indeed, in this way, sensible effects have been explained by causes which fall within the senses, something most conducive to practical applications and to imitating and improving upon nature. [... ] But many sensible effects remain which we have not been able to reduce to sensible causes, like the workings of the magnet, or like the particular powers that belong to simple things, no trace of which is found in the parts derived from them through chemical analysis, as, for example, appears to be the case with poisonous or medicinal plants. Here we sometimes turn to analogy, and we are not doing badly if we can explain many things on the example and likeness of few. Thus having observed the attraction and repulsion of certain things, such as magnets and things made of amber, it seemed that one could establish the forces that are at work there and also found in other things. And so Gilbert, who was the first to write about the magnet with care, and not without good results, conjectured that magnetism also lay hidden in many other things. In this, however, he was repeatedly mistaken, as was Kepler in other respects a most excellent man who devised certain attracting or repelling magnetic fibers among the planets. It was also in this way that the common philosophers invented a certain avoidance of vacuum from a few experiments with pumps and bellows, until Galileo showed that the power of aspirating pumps, as they call them, or the power of those things into whose place air cannot come, a resistance to separation which they attributed to that avoidance of vacuum, can be overcome. 6 Torricelli, in the end, reduced it to the weight of the air above us, a palpable cause existing in nature. Nor 6 See Galileo, Two New Sciences, pp The reference is to the inseparability of two???- JC 5

6 was there any reason why they should have attributed a quality of abhorring a vacuum to Nature. For us to know that a vacuum cannot be created with any amount of force, it is sufficient for us to know that everything is, once and for all, full, and that the matter exactly filling a place cannot be squeezed into a smaller space. The sensible vacuum, which we create by machines and which nature was long believed to abhor and refuse, does not exclude subtler bodies. And so, learned men often imagined things that don t exist, and they extended too far what they did observe in certain cases. However, we should praise them because they gave us conjectures that should not be scorned, conjectures which were successful in certain respects, at least. Furthermore, we shouldn t criticize these men because they tried to put certain subordinate principles in place so that they might, step by step, advance toward their causes. But we should criticize those who hold these subordinate principles as primitive and inexplicable, as, for example, those who fabricated miracles, or those who fabricated incorporeal ideas that produce, regulate, and govern bodies, those who put forward the four elements or the four primary qualities as if they contain the ultimate explanation of things, or those who, uninterested in understanding the particular force by which we evacuate with pumps, the force which we find to resist our opening a bellows lacking an aperture, set up in nature which abhors, as it were, the vacuum a primitive, essential, and insuperable quality. And whoever isn t, with us, eager to know qualities hitherto hidden, that is, unknown, has invented qualities of eternal obscurity, mysterious, inexplicable, which not even the greatest genius can know or render intelligible. Such are those who, induced by the successful discovery that the great bodies of this planetary system have an attraction for one another and for their sensible parts, imagine that every body whatsoever is attracted by every other by virtue of a force in matter itself, whether it is as if a thing takes pleasure in another similar thing, and senses it even from a distance, or whether it is brought about by God, who takes care of this through perpetual miracle, so that bodies seek one another, as if they sensed each 6

7 other. However it might be, these people cannot, at any rate, reduce this attraction to impulse or to intelligible reasons (as Plato already did in the Timaeus), nor do they want to. [... ] But it is astonishing that there are those who now, in the great light of our age, hope to persuade the world of a doctrine so foreign to reason. John Locke, in the first edition of his Essay Concerning Human Understanding, judged that it is appropriate that no body is moved except through the impulse of a body touching it, as did Hobbes and Boyle, distinguished countrymen of his, and, following them, many others who strengthened mechanistic physics. But afterwards, having followed the authority of his friends, I think, more than his judgment, he retracted this opinion and believed that I know not what wonderful things can lie hidden in the essence of matter. It is just as if someone believed that there are occult qualities hidden in number, in time, in space, in motion considered in and of themselves, that is, it is just as if someone [... ] wanted to make obscure that which was already clear. Robert Boyle once refuted such views quite nicely when he rejected the thread [funiculus] binding matter together proposed by Franciscus Linus and Thomas White, because, of course, it assumed something imaginary and inexplicable which binds the very thread together. 7 But, at least, this thread was corporeal and more intelligible (indeed, intelligible in something contiguous) than the new and incorporeal attractive force, working at any distance whatsoever without any medium or means. We can scarcely imagine anything more foolish than this in nature! And nevertheless, these people seem to have thought that they said something worthy of admiration. And now 7 New Experiments physico-mechanical Touching the Spring of Air and its Effects Whereunto is added A defence of the authors explication of the experiments, against the objections of Franciscus Linus, and Thomas Hobbes (1662), in Boyle, Works, vol. I. Linus, in response to Boyle s air-pump experiments, elaborated a theory in accordance with which it is tiny threads, funiculi, that pull one s finger down at the top of an evacuated tube. This theory to explain airpump phenomena was extended to a general theory of the make-up of body. See his Tractatus de corporum inseparabilitate... (1661). JC. 7

8 they go further and find fault with the idea that the flow of the light of the stars is instantaneously diffused through the medium, by which means the Scholastics once tried to render more intelligible the operation on distant things. What might Descartes or Boyle now say if they came back? What refutations would suffice for them to bury this new and revived chimera? And once assumed, they are forced by this view of the essential attraction of matter to defend the vacuum, since the attraction of everything for everything else would be pointless if everything were full. But in the true philosophy, the vacuum is rejected for other reasons. Indeed, I myself, when young, tried in a little book of physical hypotheses to reduce all phenomena to three operative qualities, namely to gravity, elastic force, and magnetic force. 8 However, I did not deny, in fact, I explicitly judged, that they ought to be explained through the simplest and most truly primitive things, that is, through size, shape, and motion. As is well known, Democritus, together with Leucippus, was the first to try to cleanse physics of mysterious qualities, and said that qualities exist only by convention [ex opinione], that they are appearances, not true things. 9 However, one mysterious quality remained, the insuperable hardness of his atoms, or at least, the insuperable hardness he imagined to be in his atoms, and since errors are fertile soil for bringing forth further errors, from this he was also led to defend the vacuum. Epicurus added two further fictions, the heaviness [gravitas] of atoms, and their deflection without cause, which Cicero elegantly ridiculed. In his Physics, Aristotle proceeded most correctly from the report of those views, and quite clearly had already set out the position against the vacuum and atoms that Descartes and Hobbes later revived. 10 Other works in which Aristotle seems to have philosophized more crudely are either not his, or were written exoterically. Gassendi also maintained atoms and the vacuum (two things both 8 The reference is to the Hypothesis Physica Nova (1671). For a more extended discussion of this book, see A Specimen of Dynamics above, pp JC. 9 Ref. to Lucretius. 10 Ref. to Descartes against void, his plenum. 8

9 mysterious and absurd). [... ] Galileo Gailei, Joachim Jungius, René Descartes, and Thomas Hobbes, to whom one can add Gassendi and his followers, setting aside atoms and the vacuum, have quite clearly purged inexplicable chimeras from physics, and having revived Archimedes s use of mathematics in physics, they have quite clearly purged inexplicable chimeras from philosophy and taught that everything in corporeal nature should be explained mechanically. [Yet they were excessively addicted to mechanical hypotheses, which are insufficiently trustworthy in themselves.] They have not sufficiently recognized the true metaphysical principles or the explanations of motion and laws of nature that derive from them. Therefore, I tried to fill this gap, and have at last shown that everything happens mechanically in nature, but that the principles of mechanism are metaphysical, and that the laws of motion and nature have been established, not with absolute necessity, but from the will of a wise cause, not from a pure exercise of will, but from the fitness of things. I have shown that force must be added to mass, but that force is exercised only through an impressed impetus. Instead of Archae, intelligences or plastic faculties, instincts, anti-sympathies or similar qualities, the artifice of divine mechanism is sufficient for explaining how things work, especially in the organic bodies of plants and animals, keeping only the perception and appetite of the soul, having eliminated all physical influx of body into soul or of soul into body. But even if not all bodies are organic, nevertheless organic bodies lie hidden in everything, even in inorganic bodies, so that all mass, either unordered or completely uniform in appearance, is within itself not uniform but diversified; ordered but not confused in its diversity. And so, I have shown that organisms are everywhere, and nowhere is there chaos unworthy of wisdom, and that all organic bodies in Nature are animated, but neither souls nor bodies change one another s laws. I have shown that everything in bodies takes place through shape and motion, everything in souls through perception and appetite; that in the latter there is a kingdom of final causes, in the former a kingdom of efficient causes, which two kingdoms are virtually independent of one another, but nevertheless are 9

10 harmonious; that God (the common final and efficient cause of things) accommodates everything to his ends through intermediaries that act through themselves, and that souls and bodies, though infallibly following their own laws, agree nevertheless through a harmony pre-established by God, without any physical influx between one another, and that in this a new and most beautiful proof of divinity lies hidden. Finally, I showed that bodies are only aggregates that constitute a unity accidentally [per accidens], or by extrinsic denomination and, to that extent, are wellfounded phenomena; that only monads (among which the best are souls, and among souls, the best are minds) are substances, and from this I showed that the indestructibility of all souls (which in minds is also the true immortality of the person) can be settled beyond controversy. And so, I showed that a more elevated metaphysics and ethics, that is, a more elevated natural theology and an eternal and divine jurisprudence can be established, and that from the known causes of things is derived a knowledge of true happiness. 10