 Burley’s first semantics of complex expressions runs into difficulties on some fronts, however. If no real proposition matches spoken, written, and mental propositions that are false, what is grasped when we understand the meaning of a false proposition? Moreover, real propositions have an indeterminate ontological status, since they exist partly inside the mind, partly outside, and are yet entirely independent of it. In this last case, the problem can be traced to deficiencies in his ontological system, which does not allow him to bring into focus the relation between the substantial unity and the multiplicity of real aspects of a thing (res). Thus, the real proposition, the ultimate significatum of a sentence that exists in our minds qua object of an act of judgment, can be equated with a state of affairs only in relation to its structure and semantic value, but not ontologically. In this way, Burley’s first theory of meaning, as far as the semantics of propositions is concerned, looks to be a compromise between the theories of Walter Chatton, who treats meaning as an individual thing (res), and Adam Wodeham, who argues that the meaning of a proposition is the state of affairs signified by the proposition (complexe significabile), which is not a thing.