is increased by obstacles; if we see the crystal quickly and suddenly take form with such wonderful regularity of construction, which is clearly only a perfectly definite and accurately determined impulse in different directions, seized and retained by crystallisation; if we observe the choice with which bodies repel and attract each other, combine and separate, when they are set free in a fluid state, and emancipated from the bonds of rigidness; lastly, if we feel directly how a burden which hampers our body by its gravitation towards the earth, unceasingly presses and strains upon it in pursuit of its one tendency; if we observe all this, I say, it will require no great effort of the imagination to recognise, even at so great a distance, our own nature. That which in us pursues its ends by the light of knowledge; but here, in the weakest of its manifestations, only strives blindly and dumbly in a one-sided and unchangeable manner, must yet in both cases come under the name of will, as it is everywhere one and the same—just as the first dim light of dawn must share the name of sunlight with the rays of the full mid-day. For the name will denotes that which is the inner nature of everything in the world, and the one kernel of every phenomenon.
Yet the remoteness, and indeed the appearance of absolute difference between the phenomena of unorganised nature and the will which we know as the inner reality of our own being, arises chiefly from the contrast between the completely determined conformity to law of the one species of phenomena, and the apparently unfettered freedom of the other. For in man, individuality makes itself powerfully felt. Every one has a character of his own; and therefore the same motive has not the same influence over all, and a thousand circumstances which exist in the wide sphere of the knowledge of the individual, but are unknown to others, modify its effect. Therefore action cannot be predetermined from the motive alone, for the other factor is wanting, the accurate acquaintance with the individual character, and with the knowledge which accompanies it. On the other hand, the phenomena of the forces of nature illustrate the opposite extreme. They act according to universal laws, without variation, without individuality in accordance with openly manifest circumstances, subject to the most exact predetermination; and the same force of nature appears in its million phenomena in precisely the same way. In order to explain this point and prove the identity of the one indivisible will in all its different phenomena, in the weakest as in the strongest, we must first of all consider the relation of the will as thing-in-itself to its phenomena, that is, the relation of the world as will to the world as idea; for this will open to us the best way to a more thorough investigation of the whole subject we are considering in this second book.33
§ 24. We have learnt from the great Kant that time, space, and causality, with their entire constitution, and the possibility of all their forms, are present in our consciousness quite independently of the objects which appear in them, and which constitute their content; or, in other words, they can be arrived at just as well if we start from the subject as if we start from the object. Therefore, with equal accuracy, we may call them either forms of intuition or perception of the subject, or qualities of the object as object (with Kant, phenomenon), i.e., idea. We may also regard these forms as the irreducible boundary between object and subject. All objects must therefore exist in them, yet the subject, independently of the phenomenal object, possesses and surveys them completely. But if the objects appearing in these forms are not to be empty phantoms, but are to have a meaning, they must refer to something, must be the expression of something which is not, like themselves, object, idea, a merely relative existence for a subject, but which exists without such dependence upon something which stands over against it as a condition of its being, and independent of the forms of such a thing, i.e., is not idea, but a thing-in-itself. Consequently it may at least be asked: Are these ideas, these objects, something more than or apart from the fact that they are ideas, objects of the subject? And what would they be in this sense? What is that other side of them which is toto genere different from idea? What is the thing-in-itself? The will, we have answered, but for the present I set that answer aside.
Whatever the thing-in-itself may be, Kant is right in his conclusion that time, space, and causality (which we afterwards found to be forms of the principle of sufficient reason, the general expression of the forms of the phenomenon) are not its properties, but come to it only after, and so far as, it has become idea. That is, they belong only to its phenomenal existence, not to itself. For since the subject fully understands and constructs them out of itself, independently of all object, they must be dependent upon existence as idea as such, not upon that which becomes idea. They must be the form of the idea as such; but not qualities of that which has assumed this form. They must be already given with the mere antithesis of subject and object (not as concepts but as facts), and consequently they must be only the more exact determination of the form of knowledge in general, whose most universal determination is that antithesis itself. Now, that in the phenomenon, in the object, which is in its turn conditioned by time, space and causality, inasmuch as it can only become idea by means of them, namely multiplicity, through co-existence and succession, change and permanence through the law of causality, matter which can only become idea under the presupposition of causality, and lastly, all that becomes idea only by means of these—all this, I say, as a whole, does not in reality belong to that which appears, to that which has passed into the form of idea, but belongs merely to this form itself. And conversely, that in the phenomenon which is not conditioned through time, space and causality, and which cannot be referred to them, nor explained in accordance with them, is precisely that in which the thing manifested, the thing-in-itself, directly reveals itself. It follows from this that the most complete capacity for being known, that is to say, the greatest clearness, distinctness, and susceptibility of exhaustive explanation, will necessarily belong to that which pertains to knowledge as such, and thus to the form of knowledge; but not to that which in itself is not idea, not object, but which has become knowledge only through entering these forms; in other words, has become idea, object. Thus only that which depends entirely upon being an object of knowledge, upon existing as idea in general and as such (not upon that which becomes known, and has only become idea), which therefore belongs without distinction to everything that is known, and which, on that account, is found just as well if we start from the subject as if we start from the object—this alone can afford us without reserve a sufficient, exhaustive knowledge, a knowledge which is clear to the very foundation. But this consists of nothing but those forms of all phenomena of which we are conscious a priori, and which may be generally expressed as the principle of sufficient reason. Now, the forms of this principle which occur in knowledge of perception (with which alone we are here concerned) are time, space, and causality. The whole of pure mathematics and pure natural science a priori is based entirely upon these. Therefore it is only in these sciences that knowledge finds no obscurity, does not rest upon what is incomprehensible (groundless, i.e., will), upon what cannot be further deduced. It is on this account that Kant wanted, as we have said, to apply the name science specially and even exclusively to these branches of knowledge together with logic. But, on the other hand, these branches of knowledge show us nothing more than mere connections, relations of one idea to another, form devoid of all content. All content which they receive, every phenomenon which fills these forms, contains something which is no longer completely knowable in its whole nature, something which can no longer be entirely explained through something else, something then which is groundless, through which consequently the knowledge loses its evidence and ceases to be completely lucid. This that withholds itself from investigation, however, is the thing-in-itself, is that which is essentially not idea, not object of knowledge, but has only become knowable by entering that form. The form is originally foreign to it, and the thing-in-itself can never become entirely one with it, can never be referred to mere form, and, since this form is the principle of sufficient reason, can never be completely explained. If therefore all mathematics affords us an exhaustive knowledge of that which in the phenomena is quantity, position, number, in a word, spatial and temporal relations; if all etiology gives us a complete account of the regular conditions under which phenomena, with all their determinations, appear in time and space, but, with it all, teaches us nothing more than why in each case this particular phenomenon must appear just at this time here, and at this place now; it is clear that with their assistance we can never penetrate to the inner nature of things. There always remains something which no explanation can venture to attack, but which it always presupposes; the forces of nature, the
