Euthydemus - Well then, Ctesippus, do you think it is possible to tell a lie? Ctesippus - By Zeus I do, unless I've gone mad. Euthydemus - If one lies, does one speak of the subject matter that one's speech is about, or does one not speak of it? Ctesippus - One does speak of it. Euthydemus - So if one speaks of this, does one speak of anything else among the things that are, apart from the very thing of which one speaks? Ctesippus - How could one do that? Euthydemus - Now the very thing of which one speaks is itself among the things that are, distinct from the rest of them. Ctesippus - Absolutely. Euthydemus - So someone who speaks of that thing, speaks of a thing that is? Ctesippus - Yes. Euthydemus - But someone who speaks of a thing that is, or of things that are, speaks of truths.

This dialogue appears in Plato's "Euthydemus" (283e-284b). Euthydemus argues that it is not possible to tell a lie. There must be something deeply wrong and misguided with doctrines that preclude the possibility of falsehoods in ordinary speech. Such doctrines were, however, common currency in Plato's Athens among the sophists, and they can be traced to the stage influence of Parmenides. In the "Sophist" Plato tries to rebut these doctrines and make sense of falsehoods. This task took Plato one long argument. In the two following papers, I explain what is wrong with Parmenides' view and describe Plato's long winded argument.

Concerning the published papers, please note that what is posted are manuscripts from which the published versions were created. There will be some differences between the manuscripts and the published versions. Should you actually want to cite a paper, please consult the published version.

• A two-worlds, two-semantics interpretation of Plato's Sophist. In: Greek Philosophy and Epistemology, volume II (ed. Constantine Boudouris), Ionia Publications 2001, Athens, pp. 61-68.

• On the Parmenidean misconception, in Philosophiegeschichte und logische Analyse 2: 37-49, 1999. There is an earlier version in portuguese: Exercícios eleáticos, in Disputatio 2: 3-21, 1997.

Fernando Ferreira

[The above papers are available for personal use only. In most cases, copyright resides with the publisher.]

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