The whiteness that I see in you is not a quality, but an actualization of the potentiality of whitening. In the intelligible world all the things that we call qualities are actualizations. They are called qualities because they are properties, because they differentiate the beings from each other, because in respect to themselves they bear a particular character. But since quality in the sense-world is also an actualization, in what does it differ from the intelligible quality? The sense-quality does not show the essential quality of every being, nor the difference or character of substances, but simply the thing that we properly call quality, and which is an actualization in the intelligible world. When the property of something is to be a being, this thing is not a quality. But when reason separates beings from their properties, when it removes nothing from them, when it limits itself to conceiving and begetting different from these beings, it begets quality, which it conceives of as the superficial part of being. In this case, nothing hinders the heat of the fire, so far as it is natural to it, from constituting a form, an actualization, and not a quality of the fire; it is a quality when it exists in a substance where it no longer constitutes the form of being, but only a trace, an adumbration, an image of being, because it finds itself separated from the being whose actualization it is. [Ennead II,6 (17) 3]
But is the soul herself a sense-being, if she be disposed in a particular way, and if she contain particular “reasons” (that is, faculties, virtues, sciences and arts, all of which refer to the body, and which have been classified as sense-qualities)? It has already been explained that these “reasons” themselves are not corporeal; but that they have been classified among sense-qualities only because they referred to the body, and to the actions thereby produced. On the other hand, as sense-quality has been defined as the meeting of all the above enumerated entities, it is impossible to classify incorporeal Being in the same genus as the sensual being. As to the qualities of the soul, they are all doubtless incorporeal, but as they are experiences (or, sufferings, or, passions) which refer to terrestrial things, they must be classified in the genus of quality, just as the reasons of the individual soul. Of the soul we must therefore predicate experience, however dividing the latter in two elements, one of which would refer to the object to which it is applied, and the other to the subject in which it exists. Though then these experiences cannot be considered as corporeal qualities, yet it must be admitted they relate to the body. On the other hand, although we classify these experiences in the genus of quality, still the soul herself should not be reduced to the rank of corporeal being. Last, when we conceive of the soul as without experiences, and without the “reasons” above-mentioned, we are thereby classifying her along with the World from which she descends, and we leave here below no intelligible being, of any kind whatever. [Ennead VI,3 (44) 16]