Nature is the movement without qualification of existent things. It [has] five modes.
(1) The intelligent [nature], such as exists in the Angels whose very thoughts associate with each other.
(2) The rational [nature], such as [exists] in human beings, that makes public to external [people] the invisible motions of the soul through names and words.
(3) The perceptual [nature] is the one observed in irrational beings: for they have acquired the perceptual [power], in addition to the nutritive, the growing, and the generative power.
(4) The vegetative [nature] is the one [existing] in plants: for [plants] also move themselves according to the nutritive, the growing, and the generative power.
(5) However, [there is an] inanimate [nature], as in the case of stones, insofar as they also are moved according to quality and to place: according to quality when they are heated and made cold; according to place by transposition from a place to [another] place, [being] moved by external forces.