On the Unchangeableness of God (40-42)

and that which is thoroughly ripe is then perfected, when, even if no one gathers it, it of its own accord hastens to separate itself from its kindred

And the Creator has made the soul to differ from nature in these things—in the outward sense, and imagination, and impetuosity; for plants are destitute of impetuosity and devoid of imagination, and without any participation in the outward sense. But every animal partakes of all these qualities above-mentioned, all together.

Now the outward sense, as indeed its name shows, in some degree is a kind of insertion, placing the things that are made apparent to it in the mind; for in the mind, since that is the greatest store-house and receptacle for all things, is everything placed and treasured up which comes under the operation of the sense of seeing or hearing, or the other organs of the outward senses.