What is Rhetoric and Is it Good? Exploring Plato’s Sophist

How does Plato’s conception of rhetoric develop in the Sophist? We examine this ancient dialogue in detail to find out.

Mar 10, 2023By Luke Dunne, BA Philosophy & Theology
what is rhetoric exploring plato sophist
Plato with ‘The Nine Muses – Polyhymnia (Rhetoric)’ (Johann Heinrich Tischbein, 1781, from Wikimedia Commons)


How does Plato develop his view of rhetoric in the Sophist? In this article, we begin by providing some context to the dialogue, both in terms of the historical context behind it, and its place in the Platonic corpus. It then moves on to consider Plato’s views on proper speaking previously, particularly in Ion, an earlier dialogue. It lastly moves to consider one problem of proper speaking – the so-called ‘Late Learner’s Problem’ – and what implications that has for Plato’s conception of speech and rhetoric.


In many of Plato’s dialogues, particularly some of the earliest ones, the conversation is framed around an attempt to define a specific thing or concept. Plato then, by and large, abandons this framing for some of the dialogues of his ‘middle period’, allowing a more open-ended kind of investigation – one which goes beyond an attempt to reach agreement over how a certain concept could be defined, and which allows for a more open ended, constructive kind of investigation into things themselves. Following this middle period, Plato appears to reorient his method of investigation and focuses once again on attempting to define concepts. Yet this later period is not a genuine reversion to form so much as the reintegration of an old method in the service of distinctly constructive projects.


Who Were the Sophists in Plato’s Sophist?

Protagoras by de Ribera, 1637, from Wikimedia Commons.


The Sophist exemplifies the development in Platonic thought particularly well, beginning with what seems to be an early-Platonic investigation, only to utterly derail said investigation with some of the most difficult and original philosophy in the entire Platonic corpus.


Before we can say what exactly rhetoric is for Plato, it is worth pausing to ask who the sophists actually were. The term ‘sophist’ is nowadays often used to refer to something quite like ‘one who is overly concerned with rhetoric’, with the implication that rhetoric constitutes the stylistic or persuasive element of speech, and this is separable from what we might call the ‘content’ of speech. A sophist is one who lacks argumentative substance.


Get the latest articles delivered to your inbox

Sign up to our Free Weekly Newsletter

However, in a Greek context the word meant something different. First, it referred to a kind of teacher of public speaking and advisor in political matters who schooled young men before they entered public life. Second, it referred to a patchwork of philosophers who also happened to hold this profession, of whom the most famous was Protagoras. The word’s modern connotation only goes to show how powerful a hold the various criticisms of Sophism have over our collective imagination.


Empty Rhetoric in Plato’s Sophist

A marble bust of Plato from the Altes museum in Berlin, 1st Century AD, via Wikimedia Commons.


What is now a definition was once a question in need of answering: are Sophists mere purveyors of empty rhetoric? It is this question which the Sophist sets out to answer, along with the natural follow-up: if the Sophist is one who speaks vacuously, how should one speak instead?


This is a question which has come up before for Plato. In fact, the notion of proper speaking and a whole host of other ways in which the concept of “right” can be understood in the domain of discourse are central concerns for Plato, and often crop up even when they’re not really supposed to be under discussion.


One dialogue to which the question of proper speaking is crucial is Ion, which although superficially about poetry, also contains certain reflections on style, performance and the effect of speech which have implications for rhetoric as well. Ion, Socrates’ interlocutor in the dialogue, is a poet who specializes in his dramatic renditions of Homer’s work. He claims to be more than a mere performer, however, but one who rightly interprets Homer’s stories for maximal dramatic effect. It is this latter claim, the claim to provide a correct interpretation in his dramatic performances, that Socrates focuses on.



A bust of Pericles, an Athenian general famous for his rhetorical prowess. Copy of Kresilas, 430BC, from Wikimedia Commons.


Socrates’ line of questioning to Ion runs as follows. First, he clarifies that as an interpreter of Homer’s work, Ion must therefore know what Homer means. And, given that Ion claims to be a specialist in Homer’s work, and doesn’t feel himself to have a gift for retelling the work of other poets, he must think that Homer speaks best, at least on his chosen topics (of which there are many). Ion accepts both of these premises, although we might rightly think him a fool to accept the latter premise in particular.


Socrates proceeds: to understand what Homer said and to know that he spoke well, we must understand the subjects of which he speaks as well (as, of course, he must have). Such claims to expertise, particularly when they concern human life in general (as Homer’s work undoubtedly must), can be subject to counter-claims. From here, Socrates observes that neither Ion, nor Homer, can substantiate the claim to be an expert on such a broad range of topics, and so Ion neither knows what Homer means, nor does Homer himself mean anything as such.


An etching of Plato by Cunego, 1783, via the Wellcome Collection.


What are the implications of this argument for rhetoric? Well, for one thing we learn that Plato considers proper speaking to be largely a matter of understanding – to speak well is to understand that of which one speaks. Language is a medium, it relates us to things, and it is knowledge of those things which counts.


Plato, at least on the basis of this argument, is proposing a criterion for proper speaking which is external to speech itself, as opposed to an internal critique based on, say, consistency (although inconsistencies and other internal problems may emerge as a result of improper speech in any case).


It is telling that one of the possible escape routes Socrates offers for Ion is the idea that the poet is divinely inspired, and merely a conduit for knowledge of a higher reality. Speech must either be substantiated by the speaker, or appeal to some higher authority for its warrant.


The Late-Learner’s Problem

A photograph of the Athenian acropolis in the modern day, 2006, unattributed, via Wikimedia Commons.


Having established that the problem of rhetoric, at least in one guise, amounts to a problem of proper speaking, we can turn to consider one such problem in the Sophist and its implications for Plato’s approach to rhetoric.


The crux of the Late Learner’s Problem is an attempt to justify saying such things as ‘x is y and x is not y’. There are three interpretations of how Plato proceeds. First, that Plato (rightly) attempts to disambiguate two meanings of ‘is’ – that is, the ‘is’ of identity (x is the same as y) and the ‘is’ of predication (x is, meaning ‘x exists’).


Crucially, those who hold that Plato is successful in distinguishing the ‘is’ of identity and the ‘is’ of predication must hold that he does so in such a way that they do not simply imply one another. We can see that they might; if I say ‘x is the same as y’, am I not also implying that ‘x exists’? The second interpretation is that, though Plato wishes to justify the coherence of statements of the form ‘x is y and x is not y’, he fails to suitably distinguish the ‘is’ of identity and the ‘is’ of predication, and for this reason fails.


Why The Two Kinds of “Is” Matter 

A marble bust of Socrates, 1st Century AD, author unknown, from the Louvre. Via Wikimedia Commons.


The conversation in the Sophist is between Theaetetus, a young man who Socrates deems to be the brightest of his generation in intellectual matters, and a stranger from Elea. Elea was home to a rival school of philosophers, of whom the most famous members are Parmenides (who is said to have founded it) and Zeno, who is best known for his various paradoxes.


Eleatic thought is far subtler and far more contentious than can be adequately conveyed here, but it is worth keeping the central metaphysical doctrine (that is, for our purposes, a theory of reality in general) of Eleatic thought in mind. That doctrine is now called ‘monism’ – it is the theory which holds that at the most fundamental level, the world is composed not of many things (as it might appear), but of just one thing.


What that ‘fundamental level’ is, and how one should define a ‘thing’, remains a matter of dispute, but it isn’t difficult to see how monism and the two kinds of ‘is’ relate to one another. A monist might wish to argue that, whenever we are forced to say that something both is and is not x, we tacitly reveal the logical incoherence of multiplicity.


Two Kinds of “Is”, Monism, and Rhetoric

A bust of Cicero, who wrote extensively about the art of rhetoric and public speaking, 1st Century BC, from Wikimedia Commons.


The antagonistic relationship between monism and the coherence of varieties of ‘is’ becomes especially clear once we consider that attributing qualities to a thing, which we nonetheless wish to posit as singular (a thing that is not merely composed of qualities), is a subspecies of the claim that something ‘is and is not x’. Consider how the Eleatic stranger introduces the Late Learner’s Problem:


“Well, when we speak of a man we name him lots of things as well, applying colors and shapes and sizes and vices and virtues to him, and in these and thousands of other ways we say that he is not only a man but also good and many other things. And so with everything else: though we assume that each thing is one, by the same way of speaking [logos] we speak of it as many and with many names…anyone can weigh in with the quick objection that it is impossible for what is many to be one and for what is one to be many, and they just love not allowing you to call a man good, but only the good good and the man a man”.


Language and the World in Plato’s Sophist

A modern day statue of Plato by Leonidas Drosis, photo taken in 2022, via Wikimedia Commons.


We have begun with a conception of ‘proper speaking’ as adherence to a criterion of external validity. If Plato is successful in defending the coherence of the argument form ‘x is y, and x is not y’ – he has to defend the consistency of our conventions of language, without using the fact that they are conventional in any way. After all, if it is external criteria which determines whether we are speaking rightly or wrongly, then whether or not we tend to speak in a certain way is quite irrelevant.


Yet notice that what happens when resolving the problem in the way many philosopher feel that Plato has – by distinguishing the ‘is’ of identity and the ‘is’ of predication – one has to posit an ambiguity in an otherwise certain feature of our language, an ambiguity that is not reflected in language itself or our instinctive use of it.


The possibility remains open that the Sophist is less of a polemic against the sophists as such, and more of a diagnosis of the sophist as a symptom of the incompatibility between ordinary speech and our attempt to give a general account of reality. The rhetorical skill of the Sophists, then, can be understood not so much as anti-philosophical as much as a symptom of philosophy’s necessary fallibility.

Author Image

By Luke DunneBA Philosophy & TheologyLuke is a graduate of the University of Oxford's departments of Philosophy and Theology, his main interests include the history of philosophy, the metaphysics of mind, and social theory.