This chapter sets out to explore the thesis that Plato, at least in his later years, in his efforts to identify the nature of his First Principle, was inclined to settle on the concept of a rational World Soul, with demiurgic functions, and that this was a doctrine that his faithful amanuensis in his last years, Philip of Opus, advanced on his own account, in the belief that in this he was developing the latest theories of his Master.

Nature for Plotinus is near the limit of intelligibility in the hierarchical universe. It is the lowest part of the soul of the cosmos. Hence, all problems in cosmology and biology, prior to their solution, need to be situated within the framework of the ultimate metaphysical explanatory principles of the One, Intellect and Soul. This chapter explores the sense in which Plotinus is and is not receptive of panpsychism, the contemporary philosophical view according to which mentality or consciousness is ubiquitous in the world. Plotinus argues for the idea that nature contemplates which seems, perhaps surprisingly, compatible with the radically anti-Platonic naturalism of panpsychists.

In this chapter, I focus on three different topics to illustrate the complicated and often surprising ways in which Aristotle’s investigations of animals and of the heavens are related to one another. After an introductory discussion of how Aristotle differentiates these different scientific investigations of nature from one another, this chapter looks at (1) the dependence of Aristotle’s account of cosmic directionality (in De caelo II.4) on his discussion of directional concepts in his account of animal locomotion (De incessu animalium 1-6); (2) the relationship between his account of gestation periods in De generatione animalium IV.10 and his understanding of the complex relationship between the solar and lunar cycles; and (3) his teleological explanation of why there are distinct male and female contributors to animal generation (and why animals generate at all) at the beginning of De generatione animalium II as it relates to his discussion of the cyclical nature of all generation that closes Generatione et Corruptione II.11.

How is the rationality of the Stoic god constituted? Commentators often look to the seventeenth-century ‘rationalists’, especially Spinoza, for their inspiration. But the Stoics say that god’s rationality is the same as ours. Since human rationality is defined as a product of concept-acquisition, it may be that the Stoics had to give an ‘empiricist’ account of divine rationality too. Hierocles’ discussion of animal self-perception shows that the Stoics had the conceptual materials for such an account.

This chapter studies the intersection of biology and cosmology from the angle of the thesis that the cosmos is intelligent in the sense that it is an agent capable of thinking, which is part of their more general thesis that the cosmos is an animal. The thesis that the cosmos is intelligent is argued for by the Stoics through different families of proofs.The present chapter focusses on one of them, called ‘F1’,and its relation to the proof of the intelligence of the cosmos in Plato, Tim. 30a2–c1. The argument-structure common to the members of F1 is (a) the intelligent is better than the unintelligent but (b) the cosmos is better than everything else; therefore, (c) the cosmos is intelligent. I argue that this argument-structure is borrowed from the Timaean proof but that, in contrast with the Timaean proof, F1 is based on a teleological theory that I call ‘cosmocentrism’, according to which the cosmos is a beneficiary, and the ultimate beneficiary, of everything that exists within it. Plato accepted cosmocentrism, but he did not use it to argue for the intelligence of the cosmos. This family, therefore, introduces a major innovation in ancient cosmological thinking.

Ancient philosophers believed that biology and cosmology are two sciences that intersect one another insofar as biological concepts explain crucial features of the cosmos and, conversely, cosmological concepts account for important biological properties and events. ‘Cosmobiology’ is the term that I shall use to refer to this view. The aim of this introduction is to present some central cosmobiological theses in antiquity, to describe how the present volume is organised, and to offer a brief overview of the chapters.

In metaphysics, Avicenna refers to the heaven as animal (ḥayawān), and to its proximate principle of motion as soul (nafs), by using the same terminology used in psychology to refer to sublunary animals and their principle. The strategy behind this approach is to account for a remote phenomenon, i.e. heavenly circular motion, through the account of an analogous but closer and thus more knowable phenonemon, i.e. animal locomotion. Thus, in metaphysics, a sort of continuity between sublunary and celestial ‘animals’ seems to be posited: both are defined by means of the same terminology and share in some distinctive features. However, in psychology, where this terminology is defined, Avicenna explicitly denies that sublunary and celestial ‘animals’ can be referred to in the very same way, except by equivocation. This position rests on the discontinuity between the sublunary and celestial realms that is posited in psychology. Given that Avicenna’s attitude towards this issue is not consistent, the aim of this chapter is to shed some light on the use of the terms animal and soul in psychology and in metaphysics, in order to ascertain whether they have the same meaning when they are applied to celestial and sublunary entities.

The chapter explores how the Stoics account for the totality of movement in the cosmos – in other words, the agency of the world. The Stoics take the world to be a complex and divine living-being. Their physics combines what today we might call physics, biology and theology. The Stoics put forward two premises that appear to be in tension. First, they claim that the active principle is the sole source of movement and cause of everything. Second, they offer a scala naturae according to which kinds of entities differ by the way in which they move and jointly co-cause all movement in the world. This One-Many Problem is the Stoic version of what is later called the problem of free will and determinism, or so I argue. As the Stoics conceive of the problem, the challenge consists in showing how both premises – One Cause and Many Causes – are true. The Stoic approach strikes me as attractive, both because it looks at humans together with animals and other parts of the world and because of its upshot for human agency. Our reasoning, including our decision-making, constitutes some of the causes that co-cause the world’s overall movements. What remains puzzling, however, is that our reasoning is subject to norms. Ultimately, I argue, the puzzle is how norms for practical reasoning fit into the physical world. This reconstruction does justice to the evidence. It recognizes that the Stoics address human movement in the context of a scala naturae. And it predicts what indeed we find: a wide range of texts about the status of human assent, indicative of the awareness that this is not an easy topic.

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.

This chapter does not directly address the issue of the relations between biology and cosmology as such, although it refers in passing to Galen’s deployment of the microcosm/macroscosm model for the understanding of the nature of the human form and its relation to, indeed its mirroring of, the overall structure of the universe. But it does deal with how and why Galen thought that a proper understanding of the enormous complexity, goal-directedness, economy of animal and pre-eminently human structures demands explanation in terms of a providential, artistic and indeed aesthetically motived designer-god. That is, a proper understanding of the biosphere, and in particular of human physiology, demands a commitment to, and an understanding of, what Galen takes to be a fundamental cosmological fact, namely that the universe is indeed providentially ordered. The bulk of this chapter is devoted to teasing out in detail the nature and working-out of these fundamental commitments.

Plato’s cosmology in the Timaeus can be seen as being framed in biological terms, since it claims the universe as a whole to be a living being, more specifically, a created god. In this chapter, I show that the central assumption that leads Plato to understand the created cosmos as a living being is the idea that the world is as good as possible. In a second step, I want to show that this assumption of the world’s bestness is also responsible for two important twists to the biological framing Plato uses. First, being as good as possible also implies that the world is self-sufficient, which means that many of our common biological notions are of no relevance for an account of the cosmos as a living being. Secondly, I show that while Plato gives an account of all kinds of living beings, his assumption of the bestness of the world leads him to be ultimately interested only in rational living beings. Accordingly, what starts out in biological terms turns into a form of rational psychology and rational theology. This will finally lead to a discussion whether Plato works with a consistent notion of life in the Timaeus.

The theory of recapitulation is best known in its evolutionary form, as it was this form that Ernst Haeckel captured with his famous biogenetisches Grundgesetz (‘ontogeny is nothing other than a succinct recapitulation of phylogeny’). It is a theory that is justifiably associated above all with the natural philosophy of the eighteenth to twentieth centuries. Yet some historians of science have raised questions about its roots in ancient thought, and this chapter aims to explore a selection of natural philosophers in antiquity (especially Empedocles, Aristotle, Plato and Plotinus) in order to determine how close they came to recapitulation theory. Certain Presocratic thinkers appear to have anticipated recapitulation theory in some evolutionary sense, but it is no longer to be found in Aristotle and the Platonic tradition. This is not simply because Aristotle and Plato rejected evolution, since there are also non-evolutionary versions of recapitulation which are founded upon hierarchical theories of transcendental morphology. It is shown that only the Neoplatonists can be credited with a clear commitment to transcendental morphology but that even they develop their transcendental morphology in a way that does not lend itself to recapitulation theory.

The chapter focuses on the role of the heart and the image of the world as a cardiovascular system in the post-Chrysippean tradition. Within this picture, then, it will be shown that in later Stoicism, not only the heart but the blood first and foremost was used in explaining the essence and features of the soul and eventually employed as a model to explain the universe. The existence of a ‘hematic’ variation within cardiocentrism will thus be highlighted, which allows some Stoics to better justify the spreading and the action of the soul within the body, and that of god throughout the cosmos. By doing so, the post-Chrysippean tradition recalls Empedocles’ position. This topic will be first of all studied in Diogenes of Babylon, who stresses the importance of the heart in the wake of his master Chrysippus, yet apparently providing a different definition of the soul as (made of) blood. The chapter examines then Posidonius, whose cardiocentrism – though not strictly ‘hematic’ – differs from that of both Aristotle and Chrysippus and is crucial for his understanding of living beings and natural phenomena. Lastly, the contribution considers Seneca and Manilius, who often represent the universe as a cardiovascular system enlivened by a network of blood vessels.