Chalmers’ Two-dimensional Semantics

There are three core notions in the philosophical research of the mind-body problem—Meaning, Reason and Modality. With the combination of Kantian thesis, Neo-Fregean thesis and Carnapian thesis, we can build up a golden triangle containing these three important notions of the human understanding. However, with Kripke’s argument of necessary a priori in the Kantian thesis, the golden triangle collapsed. Still, there are many philosophers using these three core notions as a foundation to explain how we know the external world, and they realized that there could be different dimensions in the question. Among them, Stalnaker revealed a possibility of Modality in another dimension; Kaplan discovered a new connection between necessary and a priori; Evans found a kind of deep necessity; Davies&Humberstone extended the definitions of the factual world and the possible world with two-dimensional operators; Jackson came up with a theory of A-intension and C-intension.Chalmers raised a universal theory of two-dimensional system, in which he two-dimensionalized the Carnapian thesis and the Neo-Fregean thesis while constructing his two-dimensional semantic, thus recovered the golden triangle in a two-dimensional level. Though not100%well grounded is the Chalmers’ theory, he somehow recovered or say extended the golden triangle in a certain degree.The possible forms of future two-dimensional semantic are infinite, and discussions of the three notions before, including Meaning, Reason and Modality, should be a part of a infinite semantic. There is no once for all answer solving the problem "how do human know the external world", we even could not have a finite answer about this question, because this problem involve the cognitive subject himself. As thoughts of cognitive subject himself are infinite in theory, reflexive propositions about how a cognitive subject knows should be expanded infinitely in theory. Each possible kind of the expansion could be a semantic, and thus could form a new conceptual triangle.