Compendium on the Soul

AVICENNA

...[they accor]d with this intellectual apprehension, while some of them do not apprehend with it, such as the donkey and the horse. Furthermore, we find the power of movement original: "virtutem motivam" to be more common than the apprehensive power; for we see that plants are devoid of the latter. Therefore, it is proven to us that the power in which animals and plants share is more common than the apprehensive and motive powers found in the animal. Each of these, in turn, is more common than the rational power original: "virtus rationalis" which exists in man.

A

The power of the soul is therefore found to be ordered or demonstrated according to the consideration of what is common and what is specific. This is shown through three levels: the first is known as the vegetative power original: "virtus plantativa uel uegetatiua", because plants and animals share in it. Through the second, the animal power is known. And through the third, the rational power is known. Thus, the first division of the soul is based on the consideration of these three powers. The discourse regarding the definition of the soul in a universal sense—that is, absolutely within its genus—will be explained as follows. For among those things which are manifest, every natural body is composed of hyle original: "heiule," a Latinization of the Greek hyle, meaning raw material or wood. (that is, of matter) and of form. Indeed, it is a property of matter itself that a natural body is acted upon through it. For a sword does not cut because of its iron, but rather because of its sharpness, which is its form; and it is not acted upon or broken except because of its iron, not because of its sharpness. It is also a property of matter that bodies do not differ because of it. For earth does not differ from water because of its matter, but rather because of its form. Furthermore, matter does not confer or grant a specific essence to natural bodies except in potentiality original: "in potentia"; the capacity to become something rather than being it already.. For "humanity" does not exist as an acquired reality in a human being simply from the four elements, but only potentially. However, the property of form is that through it a body attains its specific operation; for a sword does not cut by means of iron, but by sharpness. Likewise, bodies are not diverse except through form. Earth is not diversified from water except by its form, not by its matter.

B

And indeed, natural bodies do not acquire their actual essence original: "essentiam suam actualiter" except from form. For a human being does not possess humanity in actuality original: "actu" except from the form itself, not from the matter of the four elements...