De Defectu Oraculorum

All this, however, has been put in a way that is more plausible than true. Look at it in this way, my dear Demetrius, said I; when he says of the bodies that some have a motion towards the centre and downwards, others away from the centre and upwards, and others around the centre and in a circular path, in what relation does he take the centre?[*](Cf.Moralia, 925 b and 1054 b.) Certainly not in relation to the void, for according to him it does not exist. And according to those for whom it does exist, it has no centre, just as it has no point where it begins or where it ends;

for these are limitations, and the infinite has no limitations. And if a man could force himself, by reasoning, to dare the concept of a violent motion of the infinite, what difference, if referred to this, is created for the bodies in their movements? For in the void there is no power in the bodies, nor do the bodies have a predisposition and an impetus, by virtue of which they cling to the centre and have a universal tendency in this one direction. It is equally difficult, in the case of inanimate bodies and an incorporeal and undifferentiated position, to conceive of a movement created from the bodies or an attraction created by the position. Thus one conclusion is left: when the centre is spoken of it is not with reference to any place, but with reference to the bodies. For in this world of ours, which has a single unity in its organization from numerous dissimilar elements, these differences necessarily create various movements towards various objects. Evidence of this is found in the fact that everything, when it undergoes transformation, changes its position coincidently with the change in its substance. For example, dispersion distributes upwards and round about the matter rising from the centre and condensation and consolidation press it down towards the centre and drive it together.