This book provides a new edition of the Platonic lexica of Timaeus the Sophist and pseudo-Didymus, the only works of this kind extant from antiquity. As Timaeus explains in an introductory letter to his Roman addressee (Epist. 5–8), the purpose of such lexica is to clarify rare and difficult words in the dialogues of Plato. In spite of the uncertain relationship between the two texts, V. identifies a number of important connections in his detailed introduction. Here, the lexica of Timaeus and pseudo-Didymus are presented together for the first time.

Both texts pose a considerable challenge for any editor, as they survive in a highly epitomised and interpolated state. Preserved in a single manuscript, Timaeus' Lexicon Platonicum contains a number of non-Platonic entries relating to Herodotus and other classical authors. These interpolations likely began as marginal notes that entered the archetype at an ancient phase of the work's transmission. For pseudo-Didymus' De dubiis apud Platonem lectionibus, there is a more extensive manuscript tradition, but the original form of the text is still difficult to reconstruct. In general, the glosses are arranged in no particular order, but glosses 11–42 are organised alphabetically, and at the end of the text, glosses 51–5 express criticism of Plato's Attic usage (συνήθεια Ἀττική). V. suggests this organisation is not original to the work, but must have been devised by a later anonymous editor (p. 252).

The introductory discussions set out the complex textual tradition of both lexica and review questions of authorship and sources. By examining other lexicographical sources and Platonic scholia, V. finds that Hermias of Alexandria, Cyril and the author of Lexicon αἱμωδεῖν had access to a more complete redaction of Timaeus' work. He also observes that the Etymologicum Genuinum, which is attributed to Photius, preserves more extensive glosses from pseudo-Didymus' lexicon. V., however, stresses that the author of Etymologicum Genuinum did not make direct use of De dubiis, but derived his glosses from an intermediary source: an earlier redaction of Συναγωγὴ λέξεων χρησίμων ἐκ διαϕόρων σοϕῶν τε καὶ ῥητόρων πολλῶν (= Σ*). Because of this indirect relationship, V. does not use the Etymologicum Genuinum to reconstruct the archetype of pseudo-Didymus' text.

V.'s conclusions about authorship are largely negative. He emphasises that there is not enough information outside the lexica themselves to establish a secure attribution. Likewise, this lack of evidence makes it difficult to determine a precise chronology for both works. Hermias of Alexander (fifth century) provides a terminus ante quem for Timaeus, as he seems to have referred to the Lexicon Platonicum in his commentary on Phaedrus 244e2. Based on Timaeus' use of Phrynichus (second century), V. places the terminus post quem at the beginning of the third century. Falsely attributed to Didymus Chalcenterus (first century b.c.), De dubiis appears to date somewhere between the third and ninth centuries. V. argues that pseudo-Didymus' text was written later than Timaeus' text, for a number of glosses in De dubiis seem to be taken from the Lexicon Platonicum.

The editions are accompanied by extensive apparatus critici, which V. helpfully divides into three sections: the first identifies the loci Platonici to which the lemmata refer; the second discusses lexicographical parallels; and the third lists variant readings and textual problems. As the edition does not contain a full commentary, the information in these sections represents the most detailed analysis of the texts themselves. In the apparatus, V. challenges a number of readings proposed by M. Bonelli in her edition of Timaeus' lexicon (Timée le Sophiste: Lexique platonicien [2007]). In one instance, he rejects Bonelli's (much criticised) emendation of βλάξ to βλακικός (p. 115), citing as evidence Hesychius (α 671) to support the manuscript's reading.

V. refers to his own negative review of Bonelli, as well as one by K. Alpers, to justify the need for another edition of Timaeus' Lexicon Platonicum. It is clear from the number of corrections in his apparatus criticus that he presents a more reliable reconstruction of the text. Moreover, his decision to place Timaeus alongside pseudo-Didymus makes it possible to compare how these authors understood particular Platonic terms (e.g. περιαγειρόμενοι). For those unfamiliar with ancient lexicography, V.'s volume may pose certain challenges, as he does not give information about the date and textual state of several of the sources he mentions. A more accessible overview of the types of lexicographical activity current in antiquity is provided by J. Barnes's introduction to Bonelli's text and commentary. None the less, V.'s edition is an indispensable tool for those interested not only in ancient lexicography but also the study of Plato and Platonic traditions.