Ancient and Philosophy of Medieval Language

In the Cratylus, the one dialogue he devoted exclusively to questions about language, Plato (c. 428–348 or 347 B.C.E.) contrasts two ways of explaining how words link with things. Is it purely a matter of "convention and agreement," so that "whatever name you give to something is the right one"? Or are some words naturally suited to stand for certain given things? Superficially, Plato certainly seems to lend support to the latter, naturalist answer, exploring through usually fanciful etymology how words can be analyzed into significant elements (for instance, psuchos—soul—"derives" from echei—has/holds—and phusin—nature), and even attributing aspects of meaning to the sounds of individual letters. Yet Plato also points, by irony and more directly, to the inadequacies of such naturalism. Other philosophical schools, such as the Stoics and Epicureans, held to a naturalist view without such reservations.

But not Aristotle (384–322 B.C.E.). He was clearly a conventionalist: a name is "a spoken sound significant by convention." But how do such spoken sounds link with the world? In On Interpretation (16a), Aristotle writes that

Spoken sounds are symbols of affections in the soul, and written marks symbols of spoken sounds. But what these are in the first place signs of—affections of the soul—are the same for all; and what these affections are likenesses of—actual things—are also the same.

Aristotle's semantic scheme, in which things are signified by words only through the intermediary of thoughts or mental images ("affections of the soul"), is underwritten by his psychology and metaphysics. Human beings know about the world through being affected by the forms that account for things being as they are: the heat of a hot stone, for instance, or the humanity that makes someone a human. Aristotle is therefore justified, to his own way of thinking, in supposing that although words vary from language to language, the mental signs they stand for are the same for all people and can correspond directly with the objects themselves.