The book is the second one in the series Cambridge Source Books in Post-Hellenic Philosophy and follows R.W. Sharples's Peripatetic Philosophy 200 bc to ad 200 (2010). It consists of 20 chapters, an introduction, glossary, references, catalogue of Platonists and two indexes. In the very concise introduction B.-S. delineates the main features of his approach. He is not focusing on the reconstruction of the Platonic tradition in the sense of ‘Platonism’ seen as a particular methodology and view of reality (proposed by L.P. Gerson, From Plato to Platonism [2013] and, now, Platonism and Naturalism [2020]), but tries to provide the more historical and polemical context for the authors and texts presented in the volume. For instance, B.-S. is interested in the Platonism of the imperial age as a new philosophical movement whose cornerstone is the rejection of materialism and of Hellenistic philosophy (including the Hellenistic Academy).

In the introduction B.-S. also explains his method of defining the philosophical current presented in the book, referring to two general commitments shared by the Platonists in question: the claim that there are immaterial and eternal causes of the world and that Plato is always right. The second criterion, especially, neatly leaves Aristotle and his problematic position in imperial Platonism out. The first, however, raises another question, namely, how broad the Platonist tent should be. B.-S. uses a metaphor of family or family resemblance to point out that the authors who appear in the volume are not only self-described Platonists, which would be the easiest way of selection. Rather, he decides to include also authors such as Philo of Alexandria and Numenios of Apamea, neither of whom would describe himself as a Platonist or a faithful adherent or exegete of Plato.

Interestingly, there is not much about Christian authors or Christian Platonists in the introduction, even though it is probable that it was mostly them who were studying Philo (except, of course, for the Jewish authors) and were actually inspired by him. Christianity, Gnosticism and Hermetism are mentioned as currents within a general anti-materialist, cultural trend of the imperial age, and later in the book B.-S. occasionally says something about Christian Platonism (not surprisingly, when discussing issues like the temporal beginning of the world or providence). But the reasons for leaving Christian authors out (understandable as they might be in a volume over 600 pages) are not clearly spelled out. A similar case could be made, to a certain extent, with regard to the corpus Hermeticum and those forms of Gnosticism that betray the influence of Platonism and thus deserved an assault by Plotinus in Enn. 2.9. B.-S. includes (hesitantly, it seems) the Chaldean Oracles in the last chapter of the volume.

The 20 chapters follow the same structure. Each chapter is devoted to a particular philosophical problem among the larger categories of cosmology, dialectic and ethics, which form the three parts of the volume. There is a short and instructive introduction with a commentary on the texts presented later in the chapter. B.-S. does not shun from giving his own, often novel and always interesting views on the given subjects. Then, there are ‘Notes and further reading’, which add details to the problems discussed earlier, but mostly provide the reader with bibliographical suggestions for further study. The entire section is divided into subsections, roughly corresponding to the structure of the introduction to the chapter, which makes it easy to use. What follows is the selection of passages, usually, but not always quite brief (half a page or a page, sometimes a sentence or two), ordered by letters (A, B, C etc.). Sometimes one author appears many times in a chapter, sometimes there is a greater variety of sources. The bibliography at the end of the book is ample, up to date and extremely useful as is the ‘Catalogue of Platonists’, which follows. Even though it sometimes reads like the Homeric catalogue of ships, it does come in handy for those of us who are not familiar with all the names that appeared on ancient inscriptions or herms with an epithet ‘Platonist’ or who cannot recite on the spot all the names of the Platonic philosophers that Porphyry drops casually in his Vita Plotini.

The volume is not just a selection of texts. It is a careful, insightful and well-organised presentation of the so called Middle-Platonist philosophy, which is as inspiring to a scholar working on the Platonic tradition as it is useful for a student who wants to learn what was going on between Plato and Plato redivivus (Augustine, Acad. 3.18.41). Particularly refreshing are the discussions of the Forms and the possibility of their knowledge in the embodied condition as well as those of the nature of the World Soul. However, what is not discussed and justified by B.-S. is his decision to render τὰ εἶδη as ‘the forms’ (instead of ‘the Forms’). Maybe it is only the bias of a Plotinian scholar, which makes me think that the distinction between the Forms (in the divine Intellect) and the forms (in the soul as well as the enmattered ones) allows the avoidance of a certain amount of confusion. Of course, it works only in print and neither Plotinus nor any other Platonist was excessively worried about the ambiguous meaning of this crucial term.

The more contentious issue is the convention of translating ὁ θεός as ‘god’. I can see no good reason for ‘god’ instead of the traditional ‘God’, the more so, because whenever B.-S. discusses Philo of Alexandria, the reader comes across ‘God’. I understand there are some reasons to change the tradition, even though I may not be sympathetic with regard to some of these reasons, for example those given by J.J. O'Donnell, where ‘god’ has his (her? its?) appearance as well (J.J. O'Donnell, Augustine: a New Biography [2005]). What I find problematic is that B.-S. does not provide the reader with any justification of his chosen way of spelling. My conjecture is that ‘God’ is reserved for the deity of the Jewish and Christian sacred scriptures (since in the case of Philo and Christian authors the upper case is used). It is obvious that the Greek word (ὁ) θεός is used in many different ways by many different authors in antiquity, but is it really necessary to abandon the tradition? What is the added value? Some explanation would be in place. On the other hand, I applaud the use of ‘creator’ for δημιουργός, which others may bemoan, instead of the usual ‘craftsman’ or, even worse, ‘demiurge’ (which would be equivalent to the ‘demon of Socrates’).

This is, of course, a minor detail, since the book is excellent, instructive, clearly and orderly composed with brilliantly written commentaries. It is hard to imagine another one to replace it soon.