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An absolute teleology, however, Bacon was willing to admit, although his conception of it was not sufficiently clear. This notion of a design in the totality of nature, which in detail only gradually becomes intelligible to us by means of efficient causes, does not refer, of course, to any absolutely human design, and therefore not to a design intelligible to man in its details. And yet religions need an absolutely anthropomorphic design. This is, however, as great an antithesis to natural science as poetry is to historical truth, and can, therefore, like poetry, only maintain its position in an ideal view of things.
Hence the necessity of a rigorous elimination of final causes before any science at all can develop itself. If we ask, however, whether this was the impelling motive for Demokritos when he made an absolute necessity the foundation of all study of nature, we cannot here enter upon all the questions thus suggested ; only of this there can be no doubt, that the chief point was there--a clear recognition of the postulate of the necessity of all things as a condition of any rational knowledge of nature. The origin of this view is, however, to be sought only in the study of mathematics, the influence of which in this direction has in later times also been very decided.19 III. Nothing exists but atoms and empty space : all else
is only opinion. Here we have in the same proposition at once the strong and the weak side of all Atomism. The foundation of every rational explanation of nature, of every great discovery of modern times, has been the reduction of phenomena into the motion of the smallest particles; and undoubtedly even in classical ages the most important results might have been attained in this direction, if the reaction that took its rise in Athens against the devotion of philosophers to physical science had not so dissophy of the Unconscious! We shall Book of returning to this late fruit have an opportunity in the Second of our speculative Romanticism.
19 Fragm. Phys., 1, Mullach, p. 357.
tinctly gained the upper hand. On the Atomic theory we explain to-day the laws of sound, of light, of heat, of chemical and physical changes in things in the widest sense, and yet Atomism is as little able to-day as in the time of Demokritos to explain even the simplest sensation of sound, light, heat, taste, and so on. In all the advances of science, in all the modifications of the notion of atoms, this chasm has remained unnarrowed, and it will be none the less when we are able to lay down a complete theory of the functions of the brain, and to show clearly the mechanical motions, with their origin and their results, which correspond to sensation, or, in other words, which effect sensation. Science must not despair, by the means of this powerful weapon, of success in deriving even the most complicated processes and most significant motives of a living man, according to the laws of the persistence of force, from the impulses that are set free in his brain under the influence of the nervous stimuli; but she is for ever precluded from finding a bridge between what the simplest sound is as the sensation of a subjectmine, for instance—and the processes of disintegration in the brain which science must assume in order to explain this particular sensation of sound as a fact in the objective world.
In the manner in which Demokritos cut this Gordian knot we may perhaps trace the influence of the Eleatic School. They explained motion and change in general as mere phenomena, and, in fact, non-existent phenomena. Demokritos limited this destructive criticism to sense qualities. “Only in opinion consists sweetness, bitterness, warmth, cold, colour; in truth, there is nothing but the atoms and empty space.” 20
Since to him, therefore, the Immediately Given-sensation—had something deceptive about it, it is easily intelligible that he complained that the truth lies deep hidden, and that he attributed more weight to reflection with regard to knowledge than to immediate perception. His reflection dealt with notions that kept close to the perceptions of sense, and were for that very reason suited to explain nature. From the one-sidedness of those whose hypotheses are mere deductions from notions Demokritos was saved by this, that he constantly tested his theory of the atomic movements by picturing it to himself in the forms of sense. IV. The atoms are infinite in number, and of endless variety
28 Mullach, 357: “ νόμο γλυκό και ρον, νόμω χροιή· ετεη δε άτομα και νόμω πικρόν, νόμω θερμόν, νόμω ψυχ- κενόν.”
of form. In the eternal fall through infinite space, the greater, which fall more quickly, strike against the lesser, and lateral movements and vortices that thus arise are the commencement of the formation of worlds. Innumerable worlds are formed and perish been considered as something quite monstrous, and yet it stands much nearer to our modern ideas than that of Aristotle, who proved a priori that besides his self-contained world there could be no second. When we come to Epikuros and Lucretius, where we have fuller information, we shall discuss more thoroughly their cosmical theory. Here we will only mention that we have every reason to suppose that many features of the Epikurean Atomism, in cases where we are not told the contrary, are due to Demokritos. Epikuros made the atoms infinite in number, but not infinitely various in form. More important is his innovation in reference to the origin of the lateral motion.
successively and simultaneously.21 The magnitude of this conception has often in antiquity 21 The main features of Atomism Epikuros, in Diogenes, x. 60, says on we must, in defect of authentic frag- this point is too superficial and unments, take in the main from Aristotle scientific to be credited to Demokri. and Lucretius; and we may remark, tos. But this judgment is too decided ; that even in these accounts, far re- for Epikuros by no means opposes, moved as they are from the ridiculous as Zeller (iii. i. 377, &c.) supposes, to disfigurements and misunderstandings the objection of there being no above of a Cicero, yet the mathematical and below in infinite space ocular evi. clearness of the premisses and the dence only; but he makes the quite connection of the individual parts has correct, and therefore, it may be, quite probably suffered. We are, there. Demokritean remark, that in spite of fore, justified in completing the defec- this relativity of “above ” and be tive tradition, though always in the low” in infinite space, yet that the sense of that mathematico-physical direction from head to foot is a defitheory on which Demokritos's whole nitely given notion, and that from system hangs. So the procedure of foot to head may be regarded as the Zeller, e.g., is undoubtedly quite opposed notion, however much we right when treating the relation of may suppose the line on which these size and weight of the atoms (i. 698- dimensions are measured to be pro702); on the other hand, there is even longed. In this direction follow the here, in the doctrine of motion, still general movement of the free atoms, a remnant left of the want of clear and clearly only in the sense of the ness so persistent in all later accounts. movement from the head to the foot Zeller observes (p. 714), that the idea of a man standing in the line, and this that in infinite space there is no above direction is that from above to below and below, appears not to have forced —the directly opposite one that from itself upon the Atomists; that what below upwards.
Here Demokritos gives us a thoroughly logical view, although one which cannot be maintained in face of our modern physics; but yet it shows that the Greek thinker carried out his speculations as far as was then possible in subjection to strictly physical principles. Starting from the erroneous view that greater bodies—the same density being assumed-fall quicker than smaller ones, he made greater atoms in their descent overtake and strike the smaller. But as the atoms are of various shapes, and the collision will not take place in the centre of the atoms, then, even according to the principles of modern mechanical science, revolutions of the atoms on their axes and lateral motions will be set up. When once set up, these lateral motions must ever become more and more complicated, and as the collision of constant new atoms with a layer of atoms already in lateral motion constantly imparts new forces, so we may suppose that the motion will continually increase.
From the lateral motions in connection with the rotation of the atoms are then easily produced cases of retrogressive movement. If now, in a layer of atoms so involved, the heavier — i.e., the larger-atoms continually receive a stronger impetus downwards, they will finally be collected below, while the light ones will form the upper stratum. The basis of this whole theory, the doctrine of the quicker descent of the greater atoms,22 was attacked by Aristotle, and it appears that Epikuros was thus induced, whilst retaining the rest of the system, to introduce his fortuitous deviations of the atoms from the straight line. Aristotle, that is, taught that if there could be void space, which he thought impossible, then all bodies must necessarily fall with equal speed, since the difference in the rapidity of the descent is determined by the various densities of the medium-as, for example, water and air. Now void space not being a medium, there is no difference therefore in the descent of different bodies. Aristotle in this case was at one with our modern science, as also in his doctrine of gravitation towards the centre of the universe. His deduction, however, is only in places rational, and is mixed with subtleties of the same kind as those by which he seeks to demonstrate the impossibility of motion in empty space. Epikuros cut the matter short, and comes to this simple conclusion : because in empty space there is no resistance, all bodies must fall equally fast—apparently in entire agreement with modern physics; but only apparently, since the true theory of gravitation of descent was wholly wanting to the ancients.
22 Comp. Fragm. Phys., 2, Mullach, impact of the atoms rushing in from p. 358, and the admirable remark of without attain a rotatory motion. Zeller, i. 717, Anm. 1, on the purely The stars, according to Demokritos, mechanical nature of this aggregation are moved by the rotating covering of the homogeneous atoms. But it of the world. Epikuros, of course, is less certain whether the vortical who was, however, it is certain, a movement (the “Kreis- oder Wirbel- very weak mathematician as compared bewegung,” Zeller, p. 715, and Anm. with Demokritos, in spite of his being 2) really played the part in Demo- later, thought it also possible that kritos's system att uted to it by the sun may maintain its continual later reporters. It seems much more revolution round the earth in conselikely that he made the vortical move. quence of the impulse once received ment of the mass of atoms of which in the general movement of the unithe world was composed only de- verse ; and if we consider how vague velop itself after the atoms, and espe- were the pre-Galilean ideas as to the cially those of the outer covering of nature of motion, we need not be surthe universe, had formed a compact prised that even Demokritos should body held together by the hooks of have made a vortical motion be develthe atoms. Such a body might then oped out of the rectilinear impact; very easily, partly by the original but convincing proofs of this view are motion of its particles, partly by the entirely wanting.