Surely every human being who is at home with such contemplations has felt a deep distrust against any idealism of that kind, as often as he has distinctly convinced himself of the eternal rigidity, omni-presence, and infallibility of nature's laws: he has arrived at the conclusion that as far as we can penetrate the heights of the telescopic and the depths of the microscopic world, everything is quite secure, complete, infinite, determined, and continuous. Science will have to dig in these shafts eternally and successfully and all things found are sure to have to harmonise and not to contradict one another. How little does this resemble a product of fancy, for if it were one it would necessarily betray somewhere its nature of appearance and unreality. Against this it may be objected in the first place that if each of us had for himself a different sensibility, if we ourselves were only able to perceive sometimes as a bird, sometimes as a worm, sometimes as a plant, or if one of us saw the same stimulus as red, another as blue, if a third person even perceived it as a tone, then nobody would talk of such an orderliness of nature, but would conceive of her only as an extremely subjective structure. Secondly, what is, for us in general, a law of nature? It is not known in itself but only in its effects, that is to say in its relations to other laws of nature, which again are known to us only as sums of relations. Therefore all these relations refer only one to another and are absolutely incomprehensible to us in their essence; only that which we add: time, space, _i.e.,_ relations of sequence and numbers, are really known to us in them. Everything wonderful, however, that we marvel at in the laws of nature, everything that demands an explanation and might seduce us into distrusting idealism, lies really and solely in the mathematical rigour and inviolability of the conceptions of time and space. These however we produce within ourselves and throw them forth with that necessity with which the spider spins; since we are compelled to conceive all things under these forms only, then it is no longer wonderful that in all things we actually conceive none but these forms: for they all must bear within themselves the laws of number, and this very idea of number is the most marvellous in all things. All obedience to law which impresses us so forcibly in the orbits of stars and in chemical processes coincides at the bottom with those qualities which we ourselves attach to those things, so that it is we who thereby make the impression upon ourselves. Whence it clearly follows that that artistic formation of metaphors, with which every sensation in us begins, already presupposes those forms, and is therefore only consummated within them; only out of the persistency of these primal forms the possibility explains itself, how afterwards--out of the metaphors themselves a structure of ideas, could again be compiled. For