Because the purity of the eye of the soul is obscured and weighed down by the corrupt body, all the powers of this rational soul born in man are laid… - Robert Grosseteste

Vacuum stands and remains a mathematical space. A cube placed in a vacuum would not displace anything, as it would displace air or water in a space already containing those fluids.

Power from natural agents may go by a short line, and then in its activity greater... But if by a straight line then its action is stronger and better, as Aristotle says in Book V of the Physics, because nature operates in the shortest way possible. But the straight line is the shortest of all, as he says in the same place.

I hold that the first form of a body is the first corporeal mover. But this is light, which as it multiplies itself and expands without the body of matter moving with it, makes its passage instantaneously through the transparent medium and is not motion but a state of change. But, indeed, when light is expanding itself in different directions it is incorporated with matter, if the body of matter extends with it, and it makes a rarefaction or augmentation of matter; for when light is itself charged with the body of matter, it produces condensation or rarefaction. So when light generates itself in one direction drawing matter with it, it produces local motion; and when light within matter is sent out and what is outside is sent in, it produces qualitative change. From this it is clear that corporeal motion is a multiplicative power of light, and this is a corporeal and natural appetite.