Now, whenever a single entity is such that one deed within it cannot be distinguished from another, it is impossible for two makers to share in its production; its creator must be one. Therefore, whoever attributes its coming-into-existence to nothing but the celestial spheres, the wandering stars, and the like, is simply mistaken.
They further claim that the Active Intellect causes the forms of the world to overflow whenever things are ready to receive them. We say to them:
Is that which overflows a substance or an accident? If it is an accident—like the sun’s rays or the light of a lamp—then the newly generated beings, namely animals, plants, minerals, and the human soul, are all substances, not accidents. If, however, what overflows is an independent substance, this is only conceivable when something is actually severed from the first, as when water overflows from a vessel; only then might it become a cause for the coming-to-be of something else.
It is well known that bodies mingle, interpenetrate, and are transformed from one condition to another. In their view this motion stems from the movement of the heavenly sphere, and the mixture produced by such transformation follows upon the motion of bodies—the two are inseparable. Hence the agent responsible for the motion cannot differ from the agent responsible for the mixture; one cannot say, “The motion is from the spheres while the mixture is from the Active Intellect.” Rather, the same agent that moves and blends is the one that effects the amalgamation, for one act entails the other, and to posit the necessary condition without its consequent is impossible.
These people say, “When the spheres move, the elements move and intermingle, becoming ready to receive the forms that overflow upon them from the Active Intellect.” This assertion is baseless. When water is poured onto earth and the two become clay, the one who mixed them is the very one who made them clay; it cannot be someone else, for they never intermingle without turning into clay. Producing the prerequisite without its inevitable concomitant is impossible.