This book is important not only for those interested in the Charmides, but also in the debate about Plato's general conception of philosophy and how to read the dialogues. T. defends (Chapter 1) and practises (Chapters 3–11) a principled unitarianism guided by a Platonic conception of wisdom as a substantive knowledge of the good (pp. 313–25). His Socrates is the expert whose knowledge (to explain those protestations of ignorance) T. characterises as not an achievement, but a continually renewed investigative practice (pp. 327–8). As he puts it, the Zalmoxian charms Socrates offers Charmides, to be identified with their investigation of σωϕροσύνη (176a–b, cf. pp. 278–9), amount to the ongoing practice of distinguishing the good in human activities, and (at least in Socrates' case) not so much a cure as a psychic regimen constituting a life participating in that good (pp. 332–3).

While Chrm. depicts the failure of Charmides and Critias to master this dialectical practice in one lesson, they are positively influenced (to justify this characterisation T. devotes Chapter 2 primarily to the case that Plato viewed Critias in a positive light unlike Xenophon). On T.'s account Plato provides indications of how the reader should build on the partial progress of Socrates' interlocutors. Here the book risks controversy, both in advancing boldly beyond the text, and by presenting paradoxically a final quasi-doctrinal synthesis of what is, after all, said to be a matter of practice not doctrine.

To take the final point first, we are not to conceive of Socratic dialectical wisdom as opposed to theory, but as transcending and producing doctrinal formulae, on the basis of T.'s appeal to the Phaedrus and Seventh Letter. The underlying rejection of a developmental approach rests on T.'s argument that modern attempts to specify a distinctly ‘early period’ Socratic elenchus are compromised by anachronistic commitments to a conception of philosophy characteristic only of the twentieth century, which distorts both the method and content of the dialogues. T. appeals instead here to P. Hadot for the significantly different character of ancient philosophy and in making his case for the subordinate role of philosophical texts to A. Nightingale, A. Danto and A. Nehamas.

Regarding content, T. takes ‘the things that are’ (τὰ ὄντα) as substantive objects of wisdom knowable only in terms of the good; regarding method, he considers the aporetic dialogues as exemplifying incompletely (owing to novice inquirers) a practice essentially continuous with that described in Ep. 7.343b–c, 343e and 344b–c, of distinguishing between the being and the quality of what is. Hence (I suppose), according to the Phaedrus' account, to which T. appeals, his own final chapter would be just a further written reminder (ὑπόμνημα) of the principles of a dialectical skill that the reader needs to reconstruct in practice for him or herself to understand properly what the dialogue is about.

I turn to T.'s detailed treatment of Chrm. (Chapters 3–10). Generally his discussion of the argumentation of the text will be extremely useful to any reader, quite independently of his account of how we should continue the dialectic ourselves. The steps of individual refutations and their terms are subjected to precise analysis and elucidation in such a way that even committed developmentalists will learn much about the reasoning in the text. For instance T. makes a systematic study of how the arguments as to the possibility and putative benefit of versions of Critias' final definition of σωϕροσύνη as self-knowledge are precisely distinguished and sequenced, on the basis of an identified difference between Critias' own interpretation of this idea, as the knowledge of knowledge, and Socrates' elaboration of it in terms suspiciously evocative of his own refutatory activity. As on other topics, T.'s engagement here with scholarship in several languages is learned, and includes a significant original contribution. The book bristles with advances on smaller points of text, translation, elucidation and argument too numerous to mention.

T.'s overall interpretation of the dialogue begins with the observation that throughout Socrates focusses on the question of the value of σωϕροσύνη, excepting only the excursus to investigate with Critias whether their reformulations of its identification with self-knowledge make it even possible. We are repeatedly reminded that this is only preliminary to resumption of the question of its benefit. As T. argues, this excursus explicitly points the reader towards a further specific inquiry regarding self-knowledge: the analysis of kinds of relative term, which, he reasons by way of Aristotle, leads to the question what, as such, the knowable is (and so whether knowledge could itself be knowable).

In brief, T.'s eventual proposals are that the knowable is the good, and that the distinction made at 174d–175a between knowledge of knowledge and of the good (so as to conclude that the former provides no benefit), should direct the reader to identify σωϕροσύνη with the latter, when understood in the light of the preceding dialectic. If the knowable is the good, then the images of a Socratic skill also called up to interpret the idea of self-knowledge direct us to a knowledge which knows not the content or method of other knowledges, but their ends as conditional goods and their relation to the absolute good; in this way the knowledge of knowledge (so understood), the knowledge of good and the virtue σωϕροσύνη are all found to be identical with Socrates' own investigative practice.

Inevitably a book on this scale produces some reservations: whether T.'s account of dialectic is best established by appeal to the Phaedrus and the Seventh Letter; why we should not expect some diagnosis of Critias' political error, notwithstanding Plato's positive regard for him; why the flagged attention to literary features produces so little of significance; whether at p. 124 with n. 48 (cf. p. 126), where T. follows van der Ben (1985), it is better to take 157b6 τινες as subject, rather than with ἰατροί in the complement after εἶναι: not all humans (τοὺς ἀνθρώπους, b5) try to be doctors, and in any case Thracian doctors are not subject to the error criticised; whether ὀνήσεσθαι (164b9) is reflexive: the middle is not primarily so, and here may just signify the overriding interest of the craftsman in producing benefit; whether T. presses the text too hard occasionally for Platonic specifications of the reader's homework (e.g. pp. 291–2 on 175b–d); whether Rep. 7.534b–c on surviving elenchus supports the claim that philosophical knowledge is not a finished result, and how that stands with T.'s claim (p. 252) that for Socrates avoiding contradiction does not constitute knowledge; and finally, whether some of the claimed allusions to exchanged and mutual goods have a textual basis, or even support his argument: cf. e.g. pp. 111–12 on 156a–b, p. 126 on 157c, pp. 169–70 on 161d–162a, pp. 186–7 on 164d–165a (least implausibly), pp. 201–2 (otherwise), and pp. 299–300 on 176c.

These reservations, and the slight liberties T. sometimes allows himself in looking beyond the dialogue's ipsissima verba for its significance, should not detract from the seriousness of his main contentions, and the light he sheds on the argumentation. Certainly a challenge is laid down as to whether any developmental account of Chrm. can make sense of its detail, and the road is open for improved explanations of how the explicit contents of a Platonic dialogue could point beyond themselves. The book is well finished, with a list of works cited and two indexes (all within measure) and only a handful of typographical and similar errors.