Online research in philosophy

The Protagoras is one of Plato's most entertaining dialogues. It represents Socrates at a gathering of the most celebrated and highest-earning intellectuals of the day, among them the sophist Protagoras. In flamboyant displays of both rhetoric and dialectic, Socrates and Protagoras try to out-argue one another. Their arguments range widely, from political theory to literary criticism, from education to the nature of cowardice; but in view throughout this literary and philosophical masterpiece are the questions of what part knowledge plays in a successful life, and how we may acquire the knowledge that makes for success. This edition contains the first commentary in English on the Greek text for almost a hundred years. The commentary provides the assistance with linguistic, literary and philosophical detail that will enable students and scholars to savour to the full the pleasures of the Protagoras.

The standard interpretation of "Theaetetus" 152-160 has Plato attribute to Protagoras a relativistic theory of truth and existence. It is argued here that in fact the individuals of Protagorean worlds are inter-Personal. (thus the Protagorean theory has public objects, but private truth). Also, a new interpretation is offered of Plato's use of heraclitean flux to model relativism. The philosophical and semantic consequences of the interpretation are explored.

Two readings of the much-discussed περιτρoπη argument of Theaetetus 170c-171c have dominated the literature. One I call "the relativity reading". On this reading, the argument fails by ignoratio elenchi because it "carelessly" omits "the qualifications 'true for so-and-so' which [Protagoras'] theory insists on" (Bostock 1988: 90). The other reading I call "the many-worlds interpretation". On this view, Plato's argument succeeds in showing that "Protagoras' position becomes utterly self-contradictory" because "he claims that everyone lives in his own relativistic world, yet at the same time he is forced by that very claim to admit that no one does" (Burnyeat 1976b: 48). I discuss and criticise both readings, and present a third, according to which the point of the argument is, very roughly, that Protagoras is committed to equating truth and truth-for, and so, further, to their intersubstitutability. This further commitment proves fatal to his argument.

Relativism, the position that things are for each as they seem to each, was first formulated in Western philosophy by Protagoras, the 5th century BC Greek orator and teacher. Mi-Kyoung Lee focuses on the challenge to the possibility of expert knowledge posed by Protagoras, together with responses by the three most important philosophers of the next generation, Plato, Aristotle, and Democritus. In his book Truth, Protagoras made vivid use of two provocative but imperfectly spelled out ideas: first, that we are all "measures" of the truth and that we are each already capable of determining how things are for ourselves, since the senses are our best and most credible guides to the truth; second, given that things appear differently to different people, there is no basis on which to decide that one appearance is true rather than the other. Plato developed these ideas into a more fully worked-out theory, which he then subjected to refutation in the Theaetetus. Aristotle argued that Protagoras' ideas lead to skepticism in Metaphysics Book G, a chapter which reflects awareness of Plato's reaction in the Theaetetus. And finally Democritus incorporated modified Protagorean ideas and arguments into his theory of knowledge and perception. There have been many important recent studies of these thinkers in isolation. However, there has been no attempt to tell a single, coherent story about how Democritus, Plato, and Aristotle responded to Protagoras' striking claim, and to its perceived implications about knowledge, perception, and truth. By studying these four figures in relation to each other, we arrive at a better understanding of an important chapter in the development of Greek epistemology.