This is the first full-length study of Neoplatonic engagements with philosophical questions concerning human embryology. W. identifies Plotinus, Porphyry, Iamblichus, Proclus, Damascius, Philoponus and Simplicius as his ‘core group’ of Neoplatonists, although he also draws upon others as he goes along. However, Porphyry's treatise To Gaurus on How Embryos are Ensouled – as W. terms it, ‘the Platonic treatise on embryology’ – forms the basis of the study. W. sees a ‘quiet revolution’ at work in Neoplatonic embryology, correcting the post-Hippocratic view that the female contribution to reproduction was inferior to the male and identifying the female contribution as the immediate active cause in reproduction (the ‘maternal actualisation thesis’).
One of the main intentions of the study is to show that the Neoplatonists did not marginalise but rather engaged with the biological sciences. However, as he notes, they only engaged very selectively with central controversies in ancient embryology, since their interest was motivated primarily by metaphysical concerns, and throughout the study W. does an excellent job of showing how their metaphysical presuppositions drive their embryology.
After outlining the general background to Neoplatonic embryology (especially Plato) in Chapter 1, ‘The Embryological Background’, W. argues in the next chapter, ‘The Metaphysical Background’, that the Neoplatonic model of procession and reversion ultimately drives Neoplatonic innovations in embryology. He also shows that the Neoplatonists make up for an explanatory gap in Plato by offering an account of the role of the Forms and formal principles in biological development. In Chapter 3, he outlines what he terms the ‘core theory’ of Neoplatonic embryology, which he helpfully contrasts with non-Neoplatonic theories in order to bring out its defining features. There is some fascinating discussion here of how Neoplatonists explained, for instance, features such as family resemblances and maternal impressions (ideoplasty) in terms of their teleological embryology. Chapter 3 is followed by an appendix, ‘Eclectic Theories’, in which W. examines several embryological theories exhibiting some Neoplatonic influence, which he classes as eclectic.
In Chapter 4, ‘The Formation and Animation of the Embryo’, W. notes that the Neoplatonists do not express much interest in the details of formation. He accounts for this (again) in terms of their overriding interest in the more generic metaphysical implications of biology, their main interest being to provide a framework to account for the realisation of intelligible forms in the sensible world, which they achieve at the biological level with the ‘core theory’. He also offers here a very helpful account of competing Neoplatonic accounts of animation of the embryo beyond their consensus about the rational soul, distinguishing between (1) a ‘seminal’ theory (the non-rational soul is present in the seed potentially) and (2) a ‘pneumatic body’ theory (the non-rational soul, like the rational soul, comes from outside).
In the final chapter, ‘Teratogenesis’, W. considers the challenge of terata for Neoplatonic teleological embryology. Besides the frustrating influence of matter, he discusses how the Neoplatonists used the distinction between particular natures and universal nature to do philosophical work to address the problem of apparent imperfection in a natural order understood in terms of causation by higher intelligible principles. However, as W. points out, they needed in addition to appeal to transmigration to account for some of the more obviously dysteleological cases. He finishes with a very useful discussion of Neoplatonic views on the challenge of retrograde evolution.
In the epilogue, he notes that this study makes the re-evaluation of the influence of Neoplatonism in the subsequent history of embryology a desideratum, since the latter field has so far not distinguished between whether later thinkers were engaging with Neoplatonic embryology itself (i.e. the ‘core theory’) or just applying the broader Neoplatonic framework itself to embryology. In this respect W.’s book will be of interest not just to Classicists but also to those interested in the reception history of Neoplatonism, and the history of medicine and embryology.
W.’s study is a groundbreaking piece of work which reveals how Neoplatonists elaborated a robust system of teleological embryology, and all scholars of Neoplatonism will want to be familiar with it. The work also has very full footnotes, as well as a bibliography of editions and translations, works cited, an index locorum and a very helpful subject index.
