Chapter 17 — That it is impossible for him to be the form of a body

Nor is it possible for God to be the form of a body or any kind of power existing in a body. For, since all bodies are found to be mobile, whatever is present in a body must be moved, at least incidentally, if the body itself is moved. The first mover, however, cannot be moved either of itself or incidentally, for it must be absolutely immobile, as has been shown. Therefore, it is impossible that God be a form or a power in a body.

Again, in order to move an object, every mover must have dominion over the thing that is moved. For we observe that motion is more rapid in proportion as the mover’s power exceeds the power of the mobile object. Therefore, that which is the very first among all movers must have the greatest dominion over all the things moved. But this would be impossible if the mover were in any way attached to the mobile object, as it would have to be if it were the body’s form or power. Consequently, the first mover cannot be a body, or a power in a body, or a form in a body. This is why Anaxagoras postulated an intelligence unmixed with matter, that it might rule and move all things.