This is a work of remarkable scope, wealth and ambition. It is a successor to The Cambridge History of Late Greek and Early Medieval Philosophy published in 1967 under the editorship of A.H. Armstrong. Since then the field of late ancient philosophy has changed dramatically. We now have reliable scholarly editions of many of the works of late ancient philosophers, competing series of commentaries and translations, the most eminent of which is Sorabji's series of translations of the Greek commentators of Aristotle that recently reached 100 volumes, and a number of specialised studies. In the course of this productivity it has become clear that many later ancient philosophers are of considerable philosophical calibre and that the study of their work sets high standards of philosophical analysis. This development has had repercussions in the entire field of ancient philosophy. Students of Presocratic thought profited from the light shed on the source of many Presocratic fragments by Simplicius, while scholars of Plato and Aristotle have seen their horizons of interpretations expand. The time was therefore ripe for a new presentation of this area of ancient philosophy and G. has to be congratulated for its undertaking.

This work, as its experienced editor admits, does not, however, replace the earlier one. This is not only because of the quality of the earlier volume, but also because of the difference in structure between the two. At a superficial level both volumes are structured in eight parts; the earlier volume contains eight thematic units, such as on Philo and early Christian thought, on Plotinus, and on the later Neoplatonists, while the new work is divided into eight parts of similar thematic coverage. The fundamental difference between the two lies in the fact that the eight sections of the earlier volume are written by eight authors, while the eight parts of the new one are written by fifty. Most of the contributors are well-known specialists on their subjects and for the most part they write in a competent and even attractive way. But their contributions come in the form of loosely connected chapters mainly covering philosophers of the period, and the editorial one-page introductions that link them do not turn them into a unified whole.

The first part, for instance, is dedicated to the period from around 45 b.c.e. to 200 c.e. and includes twelve chapters. Some focus on themes such as the transmission of ancient wisdom through libraries and doxography or the Second Sophistic, others on individual philosophers, such as Numenius, Galen and Ptolemy, and still others centre on philosophical schools, like Platonism, Peripateticism and Stoicism. One problem here is the overlap in the treatment of certain issues or figures. Antiochus of Ascalon, for instance, is discussed in four chapters, those on Cicero and the New Academy, on Platonism before Plotinus, on Stoicism and on Peripatetics. One might say that this is inevitable since Antiochus is a Platonist who sets himself in dialogue with Stoicism, Aristotelianism and the earlier Academy. But Antiochus is not an isolated case; Eudorus and Plutarch also interact with Aristotelian and Stoic views on the one hand and take stance on the previous Platonist tradition on the other. The structure of the chapters does not do full justice to this interaction. It is fair to say that the chapter on Platonism before Plotinus, written by the knowledgeable H. Tarrant, does try to give a systematic picture, yet a little later we have a chapter on Numenius too, who is discussed in the earlier chapter (albeit not in detail). One wonders why Numenius deserves an entire chapter and not Plutarch, for instance, or Sextus Empiricus, given the anti-sceptical tendencies of both Numenius and Galen. The result is a fragmented picture of Platonism in the late Roman Empire. This lack of unity pertains to all parts of the work and makes it more of an encyclopedia than a history of philosophy.

This feature, however, is not a mere accident but has to do, I think, with the editor's conviction that ‘such a history ought to be oriented first and foremost towards the positions or the doctrines held by the leading philosophers of late antiquity’ (p. 6). Yet their doctrines typically come about through their reflection on the philosophical past, both remote and proximate, and in dialogue with their present. Plotinus, Porphyry or Iamblichus do precisely this. The contributors try to do justice to this feature, but the set-up of the work does not allow them to explain why these philosophers philosophise the way they do. The case is similar with the second part that focusses on the first encounter of Judaism and Christianity with ancient philosophy, where we find chapters on Philo, Justin, Clement and Origen. What unites them is a concern about how Christianity can turn into philosophy and a preoccupation with philosophical issues such as that of cosmogony, which they commonly address drawing on the Timaeus and the account of Genesis on the one hand and on Philo on the other. These common concerns are not stressed sufficiently, because of the emphasis on individual positions.

The preoccupation with Christian philosophers is, in my view, one important feature of the work. Apart from those mentioned above, it also includes the Cappadoceans, Nemesius, Marius Victorinus, Augustine, Boethius and pseudo-Dionysius. Some of them, the editor says, are philosophers, others more theologians in nature (p. 4). A distinction between philosophy and theology in that period, however, seems rather misguided. Theology had traditionally been a part of philosophy. Aristotle is not a theologian in the Lambda of the Metaphysics and a philosopher in the Zeta. In late antiquity theology becomes dominant because of the tendency of contemporary Platonists to take as the starting point for their philosophical investigations the search for the first causes, which for them are intelligible, with God or the Good considered the highest one. Christian philosophers are similar in this regard; all crucial philosophical issues, such as that of cosmogony, the status of the human soul, the free will issue, or how man should live, are shaped, in one way or the other, by their understanding of the first principle, God. In this sense I do not see why Origen is more of a philosopher while Gregory of Nyssa more of a theologian, as the editor claims. Both seem to me to be motivated by the same kinds of questions, cosmological, psychological and ethical, and they employ similar methods.

The application of the label ‘theologian’ appears to explain the exclusion of figures like Irenaeus and Tertullian. This does not seem fair, first because both take issue with Gnosticism on all important topics, cosmology, free will, psychology and ethics, and given that the work includes a chapter on Gnosticism, and indeed a fine one, it would make sense to include them too in a synthetic chapter. Second, Tertullian's Adversus Hermogenem, in which he argues against the view that matter pre-existed creation, and his De anima are philosophically sophisticated works and illuminate the contemporary cosmological and psychological debates.

There is a general issue concerning what forms philosophy takes in late antiquity and how it is distinguished from literature, rhetoric or religion. This topic is touched on in the volume, notably in the chapters on the Second Sophistic, the Chaldean Oracles and Gnosticism. The first one, by R. Fowler, argues that contemporary rhetors embrace Plato and compete with philosophers, which means a wider diffusion of philosophy in society, while the chapters on the Chaldean Oracles and Gnosticism suggest that the lines between these schools of thought and philosophy as practised in philosophical circles is far from being clear.

Another issue is periodisation. The period of late ancient philosophy is confined to c. 200 c.e. and 900. This is, of course, a debatable topic, and agreement between scholars is unlikely to be reached. I wonder, however, why the philosophy of the first two centuries c.e. is not part of the period considered and not just background to it, as G. claims (p. 2). Numenius, Alexander and Galen are motivated by methods, concerns and questions that also motivate Plotinus. At the other end, the inclusion of Byzantine and Islamic philosophers of the tenth and eleventh centuries takes us into medieval philosophy, as the authors of these chapters admit. These chapters set out to cover four centuries each. Lack of space, however, precludes an adequate presentation of the material and even leads to oversimplifications, such as the reconstructed outline of the ‘theistic Byzantine system’ (p. 865).

An appendix lists works of all ancient authors of the period. This is very useful, yet the list is sometimes misleading, as it includes works whose existence is speculative. There follow chapter-by-chapter bibliographies and two indexes, of passages and general. The work is an editorial achievement for the management of a huge amount of material covering almost ten centuries and 1,284 pages, which are almost free of typographical errors (I spotted one on p. 194). It will serve as a standard work of reference for years to come – but not as a history.