Aristotle then shows (De C\nlo, II. I; I. 3) that “the whole heavens neither arose nor can pass away, for they are one and eternal: they neither have beginning nor end in eternal time, for they contain infinite time shut up within them.” All the other ideas are sensuous which try to speak of essential reality, and in them there always is that present which they think they have excluded. For when they assert a vacuum before the beginning of generation, this is the quiescent, self-identical, _i.e._ the eternal matter, which is thus already established before origination; they will not allow that before origination nothing exists. But in fact a thing does not exist before its origination, _i.e._ in movement there is something to move, and where reality is, there is motion. They do not, however, bring together that vacuum, the self-identical, the un-originated matter and this nothing. “That which has this absolute circular movement is neither heavy nor light; for the heavy is what moves downwards, and the light what moves upwards.” In modern physics the heavenly bodies, on the other hand, are endowed with weight, and seek to rush into the sun, but cannot do so on account of another force. “It is indestructible and ungenerated, without decrease or increase, without any change. It is different from earth, fire, air and water; it is what the ancients called ether, as the highest place, from its continuous course (ἀεὶ θεῖν) in infinite time.” This ether thus appears to be eternal matter which does not, however, take such a definite form, but which remains as it is, just as the heavens do in our conception, although here the juxtaposition begins ever to strike us more forcibly. Aristotle (De C\nlo, III. 6) shows further that the elements do not proceed from one body, but from one another; for in generation they neither proceed from what is incorporeal, nor from what is corporeal. In the first case they would have sprung from the vacuum, for the vacuum is the immediate incorporeal; but in that case the vacuum must have existed independently as that in which determinate corporeality arose. But neither do the elements arise from a corporeal, for else this body itself would be a corporeal element before the elements. Thus it only remains that the elements must spring from one another. Regarding this we must remark that Aristotle understands by origination, actual origination—not the transition from the universal to the individual, but the origination of one determinate corporeal, not from its principle, but from the opposite as such. Aristotle does not consider the universal as it contains the negative within it; else the universal would be the absolute matter whose universality, as negativity, is set forth, or is real.