 Alyngton’s theory of categories is an interesting example of that partial dissolution of the traditional doctrine which took place in between the end of the 14th and the beginning of the 15th centuries. Within Alyngton’s metaphysics, (1) the relationships between primary (or individual) substances and secondary (or universal) substances, and (2) between substances and accidents (both abstract and concrete) as well as (3) the inner natures of essential and accidental predications are so different from their Aristotelian originals that the general meaning of the categorial doctrine is deeply modified. According to Alyngton, the formal-and-essential predication and the formal-and-accidental predication would correspond to Aristotle’s essential and accidental predications respectively. But he regards remote inherence as more general than formal predication. Therefore, in his system formal predication is a sort of sub-type of the remote inherence. This means that he recognises a single ontological pattern, founded on a partial identity, as the basis of every kind of predicative relation. Thus, the praedicatio formalis essentialis and the praedicatio formalis accidentalis are very different from their Aristotelian models, as they express degrees in identity as well as the remote inherence. As a consequence, the relationships between substance and accidents and between individuals and universals (and hence the ontological status of universal substances and that of accidents) are completely changed. In Alyngton’s view, both concrete accidents, qua modes of individual substances, and universal substances, qua the main components of the natures of individual substances, are really identical-to and formally distinct-from primary substances. Moreover, in the Categories Aristotle (1) characterizes primary substances as those beings which are neither present in a subject nor predicable of a subject, and (2) considers the capacity of underlying accidents as the constitutive principle of substance, while Alyngton (1) defi nes primary substance as what (i) is apt to underlie potency and act, and (ii) has matter and form as its inner foundations, and (2) explicitly affi rms that underlying accidents is only a derivative property of substance. Finally, because of his strong propensity towards hypostatization (as we have seen, Alyngton methodically replaces logical and epistemological rules with ontological criteria and references), he interprets Aristotle’s theory of homonymy, synonymy, and paronymy as an ontological theory about real items and not as a semantic one about the relations between terms and things. In conclusion, Alyngton conflates the real and logical (so to say) levels into one: just like Burley and Wyclif , he considers logic as the theory of the discourse on being, turning on structural forms and relations, which exist in the world and are totally independent of the mental acts by which they are grasped. It is through these structural forms and relations that the network connecting the basic items of reality (individuals and universals, substances and accidents) is clearly disclosed. Yet, because of his peculiar ideas on substance and predication, his world is different from those of Burley and of Wyclif. On Burley ’s view, macro-objects (i.e., what is signified by a proper name or by an individual expression, such as ‘Socrates ’ or ‘this particular horse’) are the basic components of the world. They are aggregates made up of really different items: primary substances and substantial and accidental forms existing in them. Primary substances and substantial and accidental forms are like simple (or atomic) objects, each possessing a unique, well-defi ned nature. Although they are simple, some of these components are in a sense composite because they are reducible to something else – for example, primary substance is composed of a particular form and matter. Primary substance differs from the other components of a macro-object because of its peculiar mode of being as an autonomous and independently existing object, in contrast with the other categorial items, which necessarily presuppose it for their existence. Primary substances are therefore substrates of existence in relation to everything else. The distinction between substantial and accidental forms derives from their different relations to primary substances: substantial, universal forms disclose the natures of primary substances; by contrast, those forms that simply affect primary substances without being actually joined to their natures are accidental forms. As a result, the macro-object is not simply a primary substance but an orderly collection of categorial items, so that primary substance, even though it is the most important element, does not contain the whole being of the macro-object. On Wyclif ’s view, whatever is is a proposition (pan-propositionalism). The constitutive property of any kind of being is the capacity of being the object of a complex act of signifying. This choice implies a revolution in the standard medieval theory of transcendentals, since Wyclif actually replaces being with true. According to the common belief, verum was nothing but being itself considered in relation to an intellect, no matter whether divine or human. According to Wyclif, being is no more the main transcendental and its notion is not the first and simplest, but there is something more basic to which being can be brought back: the truth (veritas) (or true, verum). Only what can be signifi ed by a complex expression is a being, and whatever is the proper object of an act of signifying is a truth. ‘Truth’ is therefore the true name of being itself. From the ontological point of view this entails the uniqueness in type of the significata of every class of categorematic expressions. Within Wyclif ’s world it is the same (kind of ) object which both concrete terms and propositions refer to, as primary substances have to be regarded as (atomic) states of affairs. According to him, from the metaphysical point of view a singular man, for instance, is nothing but a real proposition, with its real suject (the concrete existence in time of that singular thing, say Socrates), its real predicate (the common nature, i.e., the human nature viewed qua universal), and its copula (the singular essence, i. e., the individual essence of Socrates). The result is that Wyclif ’s world consists of molecular objects, which are not simple, but composite, because they are reducible to something else, belonging to a different rank of reality, and unable to exist by itself: being and essence, potency and act, matter and form, abstract genera, species and differences. For that reason, everything one can speak about or think of is both a thing (or molecular object) and a sort of atomic state of affairs, while every true proposition expresses either an atomic or a molecular state of affairs, that is the union (if the proposition is affirmative) or the separation (if the proposition is negative) of two (or more) molecular objects. On the contrary, Alyngton’s world consists of atomic objects whose constitutive elements are abstract forms (or essences), both substantial and accidental, potency and act, and matter. In fact, according to him, unlike Burley, what is signified by a proper name or by an individual expression is a primary substance, and, unlike Wyclif, simple and complex expressions have different significata. Moreover, in his view, Socrates cannot be regarded as an aggregate, since the beings of the substantial universal forms predicated of him and those of the concrete accidental forms inhering in him coincide with the being of that primary substance Socrates himself is. Thus, if we consider Socrates from the point of view of his being, Socrates is simply an atomic object, a primary substance. If we consider him from the point of view of the essences that he contains in himself, then he is a compound of really different forms, which can exist only in it, as its components, and through its being. This is the inner sense (1) of the formula ‘really identical and formally distinct’ that Alyngton employs for explaining the relation between universals and individuals as well as the relation between substance and concrete accidents; and (2) of his description of the nature and peculiar mode of being of the primary substance: to be a primary substance is to be the being of whatever can be.