Will we therefore have to admit that activity, which is activity only because it is a quality, is something substantially different from quality? In animated beings, especially in those capable of choice because they incline towards this or that thing, activity has a really substantial nature. What is the nature of the action exercised by the inanimate powers that we call qualities? Is it participation in their qualities by whatever approaches them? Further, if the power which acts on something else simultaneously experiences (or "suffers"), how can it still remain active? For the greater thing, which by itself is three feet in size, is great or small only by the relation established between it, and something else (smaller). It might indeed be objected that the greater thing and the smaller thing become such only by participation in greatness or smallness. Likewise, what is both "active" and "passive" becomes such in participating in "activity" and "passivity." ARE THE SENSE-WORLD AND THE INTELLIGIBLE SEPARATE, OR CLASSIFIABLE TOGETHER? Can the qualities seen in the sense-world, and those that exist in the intelligible world, be classified together in one kind? This question demands an answer from those[270] who claim that there are also qualities in the intelligible world. Should it also be asked of those who do not admit of the existence on high of kinds, but who limit themselves to attributing some habit to Intelligence? It is evident that Wisdom exists in Intelligence; if this Wisdom be homonymous (similar in name only) with the wisdom which we know here below, it is not reckoned among sense-things; if, on the contrary it be synonymous (similar in nature also) with the wisdom which we know here below, quality would be found in intelligible entities, as well as in sense-things (which is false); unless indeed it be recognized that all intelligible things are essences, and that thought belongs among them. Besides, this question applies also to the other categories. In respect to each of them it might be asked whether the sensible and the intelligible form two different kinds, or belong to a single classification. 4. WHEN. 13. As to the category of time, "when," the following thoughts are suggested. IF TIME BE A QUANTITY; WHY SHOULD "TIME WHEN" FORM A SEPARATE CATEGORY?