The volumes of the 'Symposium Aristotelicum' have become the obligatory reference works for all studies on Aristotle. In this eighteenth volume a distinguished group of scholars offers a chapter-by-chapter study of the first book of Aristotle's Metaphysics. Aristotle presents here his philosophical project as a search for wisdom, which is found in the knowledge of the first principles allowing us to explain whatever exists. As he shows, the earlier philosophers had been seeking such a wisdom, though they had divergent views on what these first principles were. Before Aristotle sets out his own views, he offers a critical examination of his predecessors' views, ending up with a lengthy discussion of Plato's doctrine of the Forms. Book Alpha is not just a fundamental text for reconstructing the early history of Greek philosophy; it sets the agenda for Aristotle's own project of wisdom after what he had learned from his predecessors. The volume comprises eleven chapters, each dealing with a different section of the text, and a new edition of the Greek text of Metaphysics Alpha by Oliver Primavesi, based on an exhaustive examination of the complex manuscript and indirect tradition. The introduction to the edition offers new insights into the question which has haunted editors of the Metaphysics since Bekker, namely the relation between the two divergent traditions of the text.