Paolo Crivelli

Definitions were very important for the Stoics, even though they hesitated as to where the theory of definition should be located within their system of philosophical disciplines: some (probably Chrysippus) placed it in the methodological subsection of the logical part, others in ethics, yet others in the subsection of dialectic relating to voice. The first of these locations focuses on the epistemological side of the theory of definitions. In particular, it is connected with two roles played by definitions: sharpening our conceptions in such a way that they are more successfully applied to or withheld from entities, and endowing our conceptions with a systematic structure that makes them suitable for instruction. The Stoics do not think that definitions reveal the essence of what is defined. As for the link with the Stoic theory of language and meaning, definitions are not linguistic expressions, but sayables of a special kind (distinct from statables).

Ideas in and problems of the philosophy of language surface frequently in Plato's dialogues. This forms the basis of the present article. Some passages briefly formulate, or presuppose, views about names, signification, truth, or falsehood; others are extended discussions of important themes of the philosophy of language. Basic predicative expressions are an integral part of Plato's philosophy of language. The article further emphasizes on the importance of forms as missing standards. Plato does say that perceptible particulars derive their names from the forms they partake of.

The only passage from Aristotle's works that seemsto discuss the paradox of the liar is within chapter 25 of Sophistici Elenchi (180a34–b7). This passage raises several questions: Is it really about the paradox of the liar? If it is, is it addressing a strong version of the paradox or some weak strain of it? If it is addressing a strong version of the paradox, what solution does it propose? The conciseness of the passage does not enable one to answer these questions beyond doubt, and commentators have offered very different replies. However, a reasonable case can be made for claiming, first, that the passage in question is about the paradox of the liar, second, that it addresses a strong version of the paradox, and, third, that it attempts to solve it by assuming that someone uttering 'I am speaking falsely' (or whatever sentence-type the paradox turns on) is neither speaking truly nor speaking falsely absolutely.