 Alyngton’s choice implies an anti-reductionist approach to the matter, which is confirmed by the solution of the problem of what properly falls into the categorial fields. According to the standard realist conception, not only the accidental forms, such as whiteness, but also the compounds they cause when inhering in substances, such as a white-thing (album), fall into the categories. Burley thought that whilst the accidental forms properly fall into the categories, the aggregates made up from a substance and an accidental form do not, since they are beings per accidens, wanting in real unity. In his opinion, such an aggregate may be said to fall into a certain category, the category into which its accidental form falls, only by reduction, in virtue of the accidental form itself. On the contrary, Wyclif maintained that the aggregates built up by a substance and an accidental form fall per accidens into both the category of substance and the category which the accidental form at issue belongs to (cf. Wyclif, De ente praedicamentali, cap. 1, pp. 3–4). Alyngton combines in an original way the two slightly different opinions of Burley and Wyclif. He affirms that a thing can be said to belong to a category in a threefold way: by itself, by accident (per accidens), and by reduction (per reductionem). Something is in a category by itself if and only if the highest genus of that category is predicated by itself and and directly (in recto) of it (In Cat., cap. de numero et sufficientia praedicamentorum, p. 259). In other words, if and only if the highest genus of that category is one of the constitutive elements of the essence of the thing at issue. Accidental forms belong per se to the nine categories of accidents (In Cat., cap. de relativis, p. 300). Something is in a category by accident if and only if it is an aggregate from a substance and an accidental form. Such aggregates belong per accidens both to the category of substance and to the category in which its accidental form is by itself (In Cat., cap. de numero et sufficientia praedicamentorum, p. 259; and cap. de relativis, p. 300). Something can be in a category by reduction in two different ways: in a broad sense (large) and in a strict sense (stricte). Something is in a category by reduction large if and only if it is an aggregate, and the highest genus of a certain category is predicated only indirectly of it. Something is in a category by reduction stricte if and only if it is not an aggregate, and, (a) like differences, it is a component of the reality of a thing which is in a category by itself, but the highest genus of that category is not predicated of it; or (b) it is the privation correlated to a certain property which, in turn, is in a category by itself; or (c), like extra-categorial principle such as God, the unity, and the point, it somehow instantiates the mode of being proper to a certain categorial field, but the highest genus of that category is not one of the constitutive elements of the essence of that thing (In Cat., cap. de numero et sufficientia praedicamentorum, pp. 259–60).