the will, where no one denies it, in conscious beings, we find everywhere, as its fundamental effort, the self-preservation of every being: omnis natura vult esse conservatrix sui. But all manifestations of this fundamental effort may constantly be traced back to a seeking or pursuit and a shunning or fleeing from, according to the occasion. Now this also may be shown even at the lowest grades of nature, that is, of the objectification of the will, where the bodies still act only as bodies in general, thus are the subject-matter of mechanics, and are considered only with reference to the manifestations of impenetrability, cohesion, rigidity, elasticity, and gravity. Here also the seeking shows itself as gravitation, and the shunning as the receiving of motion; and the movableness of bodies by pressure or impact, which constitutes the basis of mechanics, is at bottom a manifestation of the effort after self-preservation, which dwells in them also. For, since as bodies they are impenetrable, this is the sole means of preserving their cohesion, thus their continuance at any time. The body which is impelled or exposed to pressure would be crushed to pieces by the impelling or pressing body if it did not withdraw itself from its power by flight, in order to preserve its cohesion; and when flight is impossible for it this actually happens. Indeed, one may regard elastic bodies as the more courageous, which seek to repel the enemy, or at least to prevent him from pursuing further. Thus in the one secret which (besides gravity) is left by mechanics otherwise so clear, in the communicability of motion, we see a manifestation of the fundamental effort of the will in all its phenomena, the effort after self-preservation, which shows itself even at the lowest grades as that which is essential.
In unorganised nature the will objectifies itself primarily in the universal forces, and only by means of these in the phenomena of the particular things which are called forth by causes. In § 26 of the first volume I have fully explained the relation between cause, force of nature, and will as thing in itself. One sees from that explanation that metaphysics never interrupts the course of physics, but only takes up the thread where physics leaves it, at the original forces in which all causal explanation has its limits. Only here does the metaphysical explanation from the will as the thing in itself begin. In the case of every physical phenomenon, of every change of material things, its cause is primarily to be looked for; and this cause is just such a particular change which has appeared immediately before it. Then, however, the original force of nature is to be sought by virtue of which this cause was capable of acting. And first of all the will is to be recognised as the inner nature of this force in opposition to its manifestation. Yet the will shows itself just as directly in the fall of a stone as in the action of the man; the difference is only that its particular manifestation is in the one case called forth by a motive, in the other by a mechanically acting cause, for example, the taking away of what supported the stone; yet in both cases with equal necessity; and that in the one case it depends upon an individual character, in the other upon an universal force of nature. This identity of what is fundamentally essential is even made palpable to the senses. If, for instance, we carefully observe a body which has lost its equilibrium, and on account of its special form rolls back and forward for a long time till it finds its centre of gravity again, a certain appearance of life forces itself upon us, and we directly feel that something analogous to the foundation of life is also active here. This is certainly the universal force of nature, which, however, in itself identical with the will, becomes here, as it were, the soul of a very brief quasi life. Thus what is identical in the two extremes of the manifestation of the will makes itself faintly known here even to direct perception, in that this raises a feeling in us that here also something entirely original, such as we only know in the acts of our own will, directly succeeded in manifesting itself.
We may attain to an intuitive knowledge of the existence and activity of the will in unorganised nature in quite a different and a sublime manner if we study the problem of the three heavenly bodies, and thus learn more accurately and specially the course of the moon round the earth. By the different combinations which the constant change of the position of these three heavenly bodies towards each other introduces, the course of the moon is now accelerated; now retarded, now it approaches the earth, and again recedes from it; and this again takes place differently in the perihelion of the earth from in its aphelion, all of which together introduces such irregularity into the moon's course that it really obtains a capricious appearance; for, indeed, Kepler's third law is no longer constantly valid, but in equal times it describes unequal areas. The consideration of this course is a small and separate chapter of celestial mechanics, which is distinguished in a sublime manner from terrestrial mechanics by the absence of all impact and pressure, thus of the vis a tergo which appears to us so intelligible, and indeed of the actually completed case, for besides vis inertiœ it knows no other moving and directing force, except only gravitation, that longing for union which proceeds from the very inner nature of bodies. If now we construct for ourselves in imagination the working of this given case in detail, we recognise distinctly and directly in the moving force here that which is given to us in self-consciousness as will. For the alterations in the course of the earth and the moon, according as one of them is by its position more or less exposed to the influence of the sun, are evidently analogous to the influence of newly appearing motives upon our wills, and to the modifications of our action which result.
The following is an illustrative example of another kind. Liebig (Chemie in Anwendung auf Agrikultur, p. 501), says: “If we bring moist copper into air which contains carbonic acid, the affinity of the metal for the oxygen of the air will be increased by the contact with this acid to such a degree that the two will combine with each other; its surface will be coated with green carbonic oxide of copper. But now two bodies which have the capacity of combining, the moment they meet assume opposite electrical conditions. Therefore if we touch the copper with iron, by producing a special electrical state, the capacity of the copper to enter into combination with the oxygen is destroyed; even under the above conditions it remains bright.” The fact is well known and of technical use. I quote it in order to say that here the will of the copper, laid claim to and occupied by the electrical opposition to iron, leaves unused the opportunity which presents itself for its chemical affinity for oxygen and carbonic acid. Accordingly it conducts itself exactly as the will in a man who omits an action which he would otherwise feel himself moved to in order to perform another to which a stronger motive urges him.
I have shown in the first volume that the forces of nature lie outside the chain of causes and effects, because they constitute their accompanying condition, their metaphysical foundation, and therefore prove themselves to be eternal and omnipresent, i. e., independent of time and space. Even in the uncontested truth that what is essential to a cause as such consists in this, that it will produce the same effect at any future time as it does now, it is already involved that something lies in the cause which is independent of the course of time, i. e., is outside of all time; this is the force of nature which manifests itself in it. One can even convince oneself to a certain extent empirically and as a matter of fact of the ideality of this form of our perception by fixing one's eyes upon the powerlessness of time as opposed to natural forces. If, for example, a rotatory motion is imparted to a planet by some external cause, if no new cause enters to stop it, this motion will endure for ever. This could not be so if time were something in itself and had an objective, real existence; for then it would necessarily also produce some effect. Thus we see here, on the one hand, the forces of nature, which manifest themselves in that rotation, and, if it is once begun, carry it on for ever without becoming weary or dying out, prove themselves to be eternal or timeless, and consequently absolutely real and existing in themselves; and, on the other hand, time as something which consists only in the manner in which we apprehend that phenomenon, since it exerts no power and no influence upon the phenomenon itself; for what does not act is not.
We have a natural inclination whenever it is possible to explain every natural phenomenon mechanically; doubtless because mechanics calls in the assistance of the fewest original, and hence inexplicable, forces, and, on the other hand, contains much that can be known a priori, and therefore depends upon the forms of our own intellect, which as such carries with it the highest degree of comprehensibility and clearness. However, in the “Metaphysical First Principles of Natural Science” Kant has referred mechanical activity itself to a dynamical activity. On the other hand, the application of mechanical explanatory hypotheses, beyond what is demonstrably