Can we distinguish and in turn defend Socrates and his philosophy, particularly as accounted for in the Apology, from the sophistry displayed by some of Socrates' contemporaries? In this volume G. answers with a resounding ‘yes’. Where do we turn, apart from the Apology, for help in carrying out such a task? According to G., we turn to the Theaetetus:

G. argues that Socrates' defence speech in the Apology serves as the subtext which grounds Socrates' inquiry into knowledge in the Theaetetus; that Socrates' remarks in the Apology about what is worth knowing, as well as the importance of leading an inquisitive life, are ‘reflected in the [Theaetetus] and illuminate it’ (p. 3). G. is quick to clarify her view on the precise connection between the two dialogues (pp. 3–4): the Apology is not meant to be interpolated wholesale into the Theaetetus; the latter dialogue is meant to serve as a distinct Socratic apologia, echoing, when appropriate, Socrates' first defence (sc. Apology). All the same, the close relation between the two must not be overlooked. In particular, we should be mindful of the fact that Socrates' trial and execution frame both dialogues; that via these two dialogues ‘Plato bids farewell to his teacher and offers an account of his philosophical practice’ (p. 5).

G. argues that, upon recognising the close relation between the Apology and the Theaetetus, certain otherwise opaque aspects of the Theaetetus become clear. The aporetic terminus of the dialogue, for example, need not entail that it is only on account of the interlocutors' failure to bring Platonic Forms into the dialogue that no positive account or definition of Knowledge as such is found. In keeping with the Apology's view of philosophy as a constant pursuit of wisdom, the Theaetetus ends just as intended: viz., as an elenctic-driven investigation that concurrently aims to rid a patient of falsehoods and better him morally (cf. pp. 8, 180–1).Footnote ¹ Indeed, the failure of each definition of knowledge examined in the Theaetetus is, according to G., perfectly understandable in light of Socrates' acknowledgement of his own epistemic limitations: Socrates in the Theaetetus does not possess genuine wisdom. Accordingly, he cannot personally arrive at a positive account of Knowledge as such in Plato's second apologia (see esp. pp. 37–51). On a related note, G. believes that recognising Socrates' epistemic limitations helps us, as readers, to elucidate the relation between the intellectual midwife and the koruphaios (‘pre-eminent’) philosopher in the Theaetetus' digression: Socrates is both like and unlike the pre-eminent philosopher. He is like him in so far as he too recognises the gods' supreme wisdom, yet he is importantly unlike him in so far as he cannot provide a positive account of the things which he seeks to understand (cf. pp. 90–101). G. adds that Socrates is ultimately ‘succeeded by the “divine” philosopher of the Sophist and Statesman [sc. the Eleatic Visitor]’ (p. 101), the Visitor being in some way (G. is unclear on this point) connected to the pre-eminent philosopher of the Theaetetus.

Apart from the introduction and conclusion, the volume is divided into four main chapters. There is also a bibliography and index. Each main chapter is named after, and naturally centres on, the four distinct definitions of knowledge that are presented in the Theaetetus. Thus Chapter 2 analyses the definition that knowledge is simply a list of sciences and crafts, whilst Chapter 3 analyses the definition that knowledge is perception. Chapter 4 focuses on the definition that knowledge is true judgement, and Chapter 5 examines the definition that knowledge is true judgement with an account. Each chapter is not strictly focused on the relevant definition of knowledge. For instance, almost every chapter addresses the running tension in the Theaetetus between, on the one hand, Socrates and his raison d'être and, on the other, Protagoras and his sophistic practices (see esp. pp. 10–12, 56–7, 108–9, 165–6).

In general, G.'s book strikes a nice balance between exposition of and critical reflection on the Theaetetus. G.'s style of writing is clear and engaging, which certainly assists the reader with grasping some of the more philosophically difficult parts of the Theaetetus. Sections 3.2–3, 3.5, 3.9, 4.2–3, 4.5–6 and 5.1–4 are especially noteworthy for their lucid and insightful comments on the relevant passages in the Theaetetus. A decent amount of secondary literature is engaged with in the book. And G. is mindful of explaining just how she stands vis-à-vis a number of other notable scholars on certain key aspects of the Theaetetus (cf. pp. 12–15). All this makes the volume a respectable addition to the (admittedly already sizeable) list of commentaries on the Theaetetus.

This is not to say that G.'s project is free from criticism. I restrict myself to making just a few comments here. G. recognises a difference between Socrates the midwife and the pre-eminent philosopher of the digression; Socrates is ‘a lesser philosopher’ (p. 94) by comparison (see her 3.7). Yet I do not believe G. is fully aware of the tension that such a noted difference brings to the foreground. If the two philosophers in the Theaetetus are in some notable way different from each other, and the pre-eminent philosopher is seriously treated as the topmost philosopher for Socrates and so Plato in the Theaetetus, then the Theaetetus evidences a notable departure from the Apology with regard to Plato's conception of philosophy. In the Apology, philosophy is straightforwardly construed as a lifetime of elenctic examination of oneself and others; Socrates denies engaging in the activities of, in particular, natural scientists and mathematicians (19b–e, cf. 18b–c, 23d). By contrast, the Theaetetus (173e ff.) incorporates these disciplines into the greater genus of philosophy. Indeed, the dialogue suggests that such disciplines – and notably not the elenctic art of intellectual midwifery – form part of the upper echelon of philosophy. How are we to square these two accounts of philosophy? This is a question that G. should directly answer, particularly in light of her overarching aim (sc. to highlight the purported close connection between the Apology and the Theaetetus). Yet, from what I can tell, she does not do so.

Furthermore, it is safe to say that the Theaetetus shares an affinity with multiple dialogues on a number of different points. G. acknowledges this (see e.g. pp. 185–6). So an important question that we ought to be asking is what specifically about the Apology, and only the Apology, makes that dialogue essential to consult when seeking clarity with regard to the subject matter of the Theaetetus? Reference (be it explicit or implicit) to Socrates' trial and execution is not restricted to the Apology or Theaetetus; neither is Socrates' disavowal of knowledge, nor the validation of Socrates' habit of quizzing others via elenchus in the hope of concurrently purging them of untenable beliefs and bettering them morally. I could go on. The point here is that the Theaetetus could just as reasonably be understood as a second Charmides, Protagoras or Gorgias. For these dialogues lend just as much (or little) to understanding the Theaetetus as the Apology does.