Theaetetus, 182c-e: Derridian-Cratylian Semantic Processualism

In Tht. 182c-e (cf. 152d-e, 157b-c – a similar argument also appears in Cra. 439d-e, an argument whose epistemological consequences are further developed in Cra. 439e-440c and Sph. 249b8-c8), Plato develops a reducto ad absurdum against the proponents of processualism (the defenders of the view that everything is always and in every respect in motion): if everything is in flux, then meaning itself is unstable and language cannot succeed in its communicative purpose (indeed, one cannot say of some x that it has the property F, e.g., that any item is white). The argument is grounded by some assumptions: first, the opponents targeted by Plato are radical Heracliteans (these are the famous μισόλογοι presented in Phd. 89c11-91b7) since they defend that absolutely everything is in perpetual flux, both concrete objects like the river and yourself and abstract objects like meanings and properties; second, a language, in order to convey information (i.e., to ensure the intelligibility or truthfulness of any discourse), requires that the meanings of words possess enough semantic stability. These two ideas are at the root of Cratylus’ mutism (Met. Γ.5 1010a7-15). Indeed, Cratylus seems to accept Plato’s argument, for he maintains that the semantic volatility of all linguistic expressions leads to the inefficiency and meaninglessness of language – and, consequently, decides to wall himself up in silence. In short, Cratylus argues that inference from the dicta ‘nothing fluent is expressible by language’ and ‘everything is fluent’ leads to ‘nothing is expressible by language’. From such a position follows, of course, a paradox of expressibility (cf. Tht. 183b2-5): Cratylus seems to express (certainly in thought, but also by gesture, i.e., to speak in the manner of Wittgenstein’s Tractatus, by showing) the claim that nothing is expressible. The legacy of the Platonic argument is interesting for two reasons: on the one hand, Frege 1884 and Strawson 1959 endorse Plato’s conclusions and use them to ostracize processualism from the metaphysical and semantic arena; on the other hand, Derrida 1967, 1972 develops a Cratylian view according to which the meaning of a word is fundamentally and irrevocably unstable (through the inexhaustible play of différance). The first part will be devoted to an analysis of Plato’s text and its readings in the scholarly literature, and the second to the philosophy of language and metaphysics, in order to assess the strength and solidity of the Platonic argument.