 The main philosophical arguments concern Gregory’s theory of the levels of being. As is well known, the aim of Gregory’s theory of complexe significabile seems to be to identify and describe an objective and independent molecular entity existing in re, which can be the significatum or the referent of a sentence, and therefore guarantees the success of our effort to understand the world. According to Gregory, this entity is the complexe significabile, that is something (1) complex but one in number, which cannot be identified with the things that the subject and/or the predicate of the sentence signify; (2) real but distinct from the extramental categorial items as well as from their corresponding mental signs; and (3) the proper and adequate object of a possible act of signification (see the prologue of his commentary on the first book of Sentences, q. 1, a. 1, pp. 3–4). It is precisely in order to provide the complexe significabile with a suitable ontological status, and every sentence with a significatum that Gregory elaborates a theory of the levels of being. According to it, the world is constituted by (1) the categorial items (or atomic objects) which are the ground of existence of every other being; (2) the states of affairs connected to them; and (3) the possible states of affairs that the atomic objects could cause if they were combined in a different way from the actual one. In fact, Gregory claims that the terms ‘something’ (‘aliquid’), ‘thing’ (‘res’), and ‘being’ (‘ens’) are synonyms, and that they have a threefold meaning. They can be taken (1) for anything signifiable in any way (that is, by a simple or a complex expression, truly or falsely)—this would be the sense in which Aristotle in the chapter de priori of his Categories says that it is necessary that an expression is called true or false when a thing is or is not. (2) For anything signifiable by a simple or a complex expression, but truly. And (3) for an existing essence or entity (ibidem, pp. 8–9). This distinction implies that (1) the complexe significabilia are not real in the same sense as the entia praedicamentalia are; (2) the complexe significabilia designated by false sentences have a feebler reality than those designated by true sentences, but they are nevertheless real and constitutive elements of the world; and (3) the reality of complexe significabilia (both true and false) is different from that of the categorial items on which this reality is grounded.