Oh man, Porphyry is just the best. From "On the Faculties of the Soul:"

On the one hand, intelligence possesses a quite peculiar nature, as is also the case with discursive reason, which is next below it. The function of the former is intuitive thought, while that of the latter is discursive thought. On the other hand, sensibility differs entirely from intelligence, acting with or without the help of organs; in the former case, it is called sensation, in the latter, imagination. Nevertheless, sensation and imagination belong to the same genus. In understanding, intuitive intelligence is superior to opinion, which applies to sensation or imagination; this latter kind or thought, whether called discursive thought or anything else [such as opinion], is superior to sensation and imagination, but inferior to intuitive thought.

That is:

Hard not to see fire, air, water, and earth in there.