Enneads IV.8: Of the Descent of the Soul Into the Body
The Procession of Intelligence Is an Excursion Downwards and Upwards
The procession of intelligence consists in descending to things that occupy the lowest rank, and which have an inferior nature, for Intelligence could not rise to the superior Nature. Obliged to act outside of itself, and not being able to remain self-enclosed, by a necessity and by a law of its nature, intelligence must advance unto the soul where it stops; then, after having communicated of itself to that which immediately follows it, intelligence must return to the intelligible world. Likewise, the soul has a double action in her double relation with what is below and above her. By her first action, the soul manages the body to which she is united; by the second, she contemplates the intelligible entities. These alternatives work out, for individual souls, with the course of time; and finally there occurs a conversion which brings them back from the lower to the higher natures.
THE UNIVERSAL SOUL, HOWEVER, IS NOT DISTURBED BY THE URGENCIES BELOW HER.
The universal Soul, however, does not need to busy herself with troublesome functions, and remains out of the reach of evils. She considers what is below her in a purely contemplative manner, while at the same time remaining related to what is above her. She is therefore enabled simultaneously on one side to receive, and on the other to give, since her nature compels her to relate herself closely with the objects of sense.