Plato’s philosophical thinking begins from views and assumptions that he presupposes in his readers or in himself, whether or not he states them explicitly. This chapter surveys the following influences: (1) Homer. (2) Political developments and the moral questions they raise. (3) The interactions of natural philosophy (‘Presocratic’ philosophy) and religion. (4) The epistemological questions arising from natural philosophy. (5) Sceptical tendencies in naturalist epistemology. (6) Sophistic and rhetoric and the intellectual and political tensions connected with them. (7) Plato’s reactions to natural philosophy, sophistic and rhetoric. (8) Socratic inquiry and its sources in drama and forensic oratory.

Throughout the early modern period, the vast majority of natural philosophers remained deeply invested in exploring the meaning of ancient philosophical texts—there was no anti-humanist turn initiated by Descartes. Discussion of ancient philosophy was used, above all, in a genealogical manner, to shed light on the historical origins of doctrinal or methodological error. Accordingly, calls for a “return” to the philosophy of the presocratics, of Hippocrates, etc., should not be understood as simplistic recourse to authority, but rather as historico-methodological arguments about the disciplinary identity of natural philosophy. Indeed, natural-philosophical innovators were often more sure of what they stood against than what exactly they stood for. Seen from this perspective, the “philosophy of the Scientific Revolution” was an anti-philosophy, driven primarily by the colonization of the discipline by physicians on the one hand and mixed mathematicians on the other; the two groups eventually coming to work in tandem to squeeze out anything that looked like metaphysical physics.

This article shows how two basic meanings of psukhē – namely ‘breath’ and ‘life’– may have helped Platonising or for that matter Stoicising doxographers to lend to various pre-Platonic philosophers the view that the world is ‘ensouled’. I do not try to systematically reconstruct how these cosmo-philosophers conceived the relationship between the world and what was to become ‘the soul’. I do suggest, however, that framing the problem in terms of ‘breath’ and ‘life’ helps us in getting a more adequate understanding both of the authentic evidence and of the history of its reception. Indeed, to the extent that it is possible, I try to reconstruct the interpretive steps that led, with various degrees of legitimacy, from the original wording to its Platonising or Stoicising deformations, which remain all too often the framework of analysis in modern interpretations. Five case studies are considered: Thales, Anaximenes, Heraclitus, some Pythagoreans and Alcmeon.

The focus of this chapter is the German philosopher Martin Heidegger. It focuses on Heidegger’s changing attitude toward Presocratic philosophy in works surrounding his involvement with the National Socialists during the Second World War. It is particularly concerned with the shifting temporalities of Presocratic philosophy in Heidegger’s thinking: from representing a rupturous, revolutionary force in his ‘Rektoratsrede’ of 1933, it becomes a long-lost, cyclical mode of thinking in his 1946 essay ‘The Saying of Anaximander’. The chapter examines the links between Heidegger’s articulations of this particular archaic era of philosophy and a contemporary discourse of responding to the National Socialists by means of the Presocratics both positively, in the work of critics like Antony M. Ludovici, and negatively, in the writings of Georges Bataille. Furthermore, it connects Heidegger’s attitude towards the significance of the Presocratics to Nietzsche’s writings about Greek philosophy both in The Birth of Tragedy and in other works of the same time, such as his unpublished tract Philosophy in the Tragic Age of the Greeks.

This chapter argues that Plato’s Laws are more than a legislative code, more than a work of political philosophy, for they call for the realisation of a project toward which Plato's work converges: to account for the whole of reality, i.e. individual, city and world. This discourse (logos) in which the law (nomos) consists derives its origin from the intellect (nous), which represents what is most akin in the soul to the divine (theos), because it is the principle of order (kosmos). This order (kosmos) which is manifested in celestial bodies must be present in man's soul, in which the intellect has to rule over pleasures and pains. Thus, an order will be assured by means of the law within the city, an order based on the contemplation of the regularity and permanence of the movements of the celestial bodies, which the citizens shall imitate, even in their movements around the territory. In the Laws, Plato brings the project of the Presocratics to its natural conclusion. The city, which is to bring about the birth of the whole of virtue in all the human beings who constitute it, is organised by means of a legislation that takes the functioning of the world as its model. The opposition between nomos and physis therefore disappears, because the law (nomos) becomes the expression of physis.