Fiona Leigh is Associate Professor in Philosophy at University College London, and is also Director of the Keeling Centre for Ancient Philosophy at UCL. She edited Self-Knowledge in Ancient Philosophy (Oxford University Press: 2020), Themes in Plato, Aristotle and Hellenistic Philosophy (Bulletin of the Institute of Classical Studies Supplements: 2021), The Eudemian Ethics on the Voluntary, Friendship, and Luck (Brill: 2012), and is co-editing (with Margaret Hampson) Psychology and Value in Ancient Philosophy (Oxford University Press: 2021 forthcoming). Her research has focused mainly on Plato’s thought, particularly his late dialogue, the Sophist. Recently, she has also become interested in self-knowledge in Plato in connection with the ‘elenctic’ method that features in his early dialogues, and in the convergence of his philosophy of mind and moral psychology on the topic of the nature of appearances and their relation to mimetic art in the Republic. She is currently working on a book on the Sophist, arguing that in critical dialogue with alternative metaphysical accounts, Plato develops and defends a causal theory of being, according to which the entities he called ‘forms’ are pre-eminent causes and beings, and not, as scholars commonly hold, universals.