In his new book, as the title suggests, Marc-Antoine Gavray proposes that Plato should be understood as the intellectual ‘heir’ of Protagoras. By this claim, Gavray does not mean that Plato simply took over Protagorean ‘material’ in any straightforward sense. Rather, what Protagoras represented for Plato was someone whose problems and ideas were important and challenging enough that they needed to be explored, reconstructed, and often refuted, if Plato’s own philosophy was to be established on a theoretically robust foundation. Moreover, Gavray argues, this philosophical Auseinandersetzung cannot be reduced to the well-known theme of ‘Plato vs. the Sophists’. For what lurks behind Protagoras’ famous doctrine that ‘man is the measure of all things’, as that doctrine is reconstructed and explored by Plato, is nothing less than democracy itself, understood not just as a particular form of government but also as a distinctive model for thinking about such themes as knowledge, dialogue, language, and education. It is in his critical engagement with Protagoras’ ‘democratic’ attitude to philosophy and to the world that Plato found the theoretical background against which to pursue his own very different philosophical and political project.
Part One explores how Plato’s own conception of a science of measurement emerges from a sustained philosophical engagement with Protagoras’ man-measure doctrine. Taking the notion of ‘measure’ (metron and cognates) as his guide, Gavray offers a thorough and detailed reconstruction of central passages from Protagoras, Theaetetus, Politicus, Philebus, and Laws. On Gavray’s reading, Plato found in Protagoras’ doctrine a lot to criticise, but also something to use and further develop. On the one hand, Plato accepts and adopts Protagoras’ conception of the measure as establishing a ‘qualitative determination’, as opposed to the purely quantitative hedonistic science of measurement envisioned in the Protagoras. What the Protagorean measure measures is not merely that the wind is warmer (or colder) than something else, but that it is cold (or warm). On the other hand, however, Plato rejects Protagoras’ attempt to found the measure in the individual human being, arguing instead that in order to truly escape the spectre of indeterminacy, the measure must be anchored in something external to the individual. Only by means of a genuinely transcendent criterion, whether it be in the form of an ethical model of behaviour or an epistemological reference, can we escape the realm of ‘the more and less’.
This latter distinction between Protagoras’ and Plato’s respective conceptions of measurement reflects a fundamental contrast between two competing visions of the world. Protagoras’ world is a world of dispute, characterised by instability and uncertainty and always open for polemic and renegotiation. But Plato insists that this vision of the world falls short, even on its own ‘democratic’ terms. Far from liberating human thought and clearing the ground for consensus and agreement, Protagoras’ rejection of any external reference means that individual measurement, while incontestably true, becomes entirely subject to the value judgments of others and that true intersubjectivity becomes impossible. Plato’s world, by contrast, is a world that promises an end to conflict by means of a shared and incontestable truth.
Part Two of the book explores the main contradiction that confronted Protagoras, according to Plato. How is Protagoras’ claim to be a teacher well worth paying for compatible with his man-measure doctrine, which insists that everyone already has an incontestable claim to the truth? By means of a detailed discussion of Protagoras’ theories of education and expertise as presented in the Protagoras and the Theaetetus, Gavray argues that this contradictory aspect of the sophist’s position, far from being a problem for him, in fact reflects an important feature both of his theory of expertise and his political vision. On Gavray’s reading, Protagoras defends a quasi-pragmatist conception of wisdom and expertise, on which the wise person is distinguished, not by having privileged access to some transcendent truth, but rather by being able to alter the conditions (hexeis) of others, so that they come to have opinions or perceptions judged by themselves to be ‘better’ than the ones they had before. What is ‘better’ cannot be determined a priori but must be established by trial and error, which means that it is always only provisionally established in an essentially open-ended process of continual improvement. Contradiction, rather than being a problem, is an inherent, central part of this process, since it is precisely by means of confronting and engaging with contradicting arguments and viewpoints that such continual improvement can come about. This Protagorean conception of expertise contrasts sharply with that of Plato, who defines the aim of expertise, the beneficial, not as what appears better to a subject in a certain condition, but as what is verified by future events, i.e. by means of an objective criterion. Contradiction, on Plato’s conception, is simply a matter of a contrast between true and false opinions, rather than something that directly and actively contributes to the exercise of expertise.
As Gavray points out, these two rival conceptions of expertise have clear political overtones. On Protagoras’ egalitarian understanding, each person remains a measure; expertise is defined by reference to the usefulness of the subjective appearances, and no one can reject those appearances as false. Plato’s conception, by contrast, has distinctly ‘aristocratic’ implications: the expert alone, in virtue of his exclusive grasp of the truth about things and about the future, is truly a measure and is set radically apart from people at large.
Part Three offers a reading of selected passages from Protagoras and Theaetetus, which Gavray reconstructs as series of attempts, on Plato’s part, at providing Protagoras’ distinctive conception of knowledge and education with the theoretical underpinnings it requires. Given the impossibility of ever anchoring any belief, word, or system of values in an objective reality, moral and philosophical training cannot hope for any form of definitive certainty. The sophist’s role must thus be conceptualised instead as a continuous activity of correction (‘redressement’) of what appears wrong, inept, or inadequate in each case. As Gavray shows, this Protagorean approach to education, as an endeavour that is always provisional and inherently open-ended, rests on a distinctive understanding of the four basic components of educational practice: dialogue, language, memory, and virtue.
Gavray makes a persuasive case for his overall claim that many of the central questions and concerns of Plato’s philosophy can helpfully be approached and understood as the result of his critical but constructive engagement with the Protagorean man-measure doctrine and what he took to be its implications and preconditions. But the value of the book stems just as much from its elaborate reconstruction of Protagoras’ ‘democratic’ philosophy itself, as it is presented in the Platonic dialogues. This reconstruction not only shows that Protagoras is provided by Plato with a coherent and sophisticated theory (as opposed to being the opportunistic and slippery charlatan he is sometimes portrayed as in the literature). It also enriches the scholarly literature by providing a number of refreshing interpretations of particular passages and themes that are not usually treated as central for understanding what is at stake, philosophically speaking, in the clash between these two thinkers. A good example of this is Gavray’s discussion of the passages on mnēmē in Theaetetus (165d and 166b-c), which he interprets as raising important philosophical questions concerning the epistemic status of memory and the persistence of personal identity at different times, which, in turn, go to core of Protagoras’ theory of wisdom as capacity for ‘improvement’. Another example is Gavray’s exploration of the role that each thinker ascribes to the study of poetry in his respective theory of moral education. For Plato in the Republic, poetry plays an important role in education by holding up moral paradigms for the young to emulate. Protagoras, by contrast, focuses on the ‘correctness’ of the language of poetry, rather than its moral content. This is not because he is merely interested in style and form, but rather because such focus serves the second-order pedagogical purpose of developing in the citizens the ability to take a critical stance towards traditional educational poetry, as well as towards language itself, and devise means of improving it in light of the requirements of the particular political context.
Since the book’s main claim concerns the affinity between Protagoras’ thought and a particular historical form of government and way of life, some readers might miss an engagement with the rich scholarship on ancient Greek democracy. Gavray’s reflections on the political ‘overtones’ of the opposition between the theories of Protagoras and Plato are extremely interesting and suggest a promising background against which to approach the interpretation of the dialogues. But Gavray does not attempt to bring his discussion of the democratic implications of Protagoras’ philosophy into conversation with modern historical studies of democratic ideology in classical Athens. The result is that it remains not entirely clear whether the democracy Protagoras is said to represent is his own idiosyncratic (and possibly anachronistic?) conception of democracy or in line with the understanding of the Athenian democrats themselves.
But this detracts only little from a book that is, after all, about ancient philosophy, not ancient history. Gavray’s book represents a valuable contribution to scholarship on Plato’s complex relation to Protagoras – and to democracy. It is, to my knowledge, the most thorough account of Plato’s discussion of Protagoras, and also among the best, which means that it should be standard reading for any future students of this interesting and important topic.