In this paper I offer an analysis of Plotinus’ argument for the existence of a quasi-psychic entity, the so-called ‘trace of soul’, that functions as an immanent cause of life for an organism’s body. I argue that Plotinus posits this entity primarily in order to account for the body’s possession of certain quasi-psychic states that are instrumental in his account of soul-body interaction. Since these quasi-psychic states imply that an organism’s body has vitality of its own , and Platonic souls (...) are no part or aspect of any body, Plotinus draws the conclusion that the soul must be a cause of the body’s life by imparting a quasi-psychic qualification to it. In so doing, Plotinus introduces elements of hylomorphism into Platonist psychology, and addresses a problem for the animation of the body that Platonic soul-body dualism may plausibly be thought to face. (shrink)

In this paper, I investigate the foundations of Plotinus’ innovative theory that prime matter is unaffectable. I begin by showing that Plotinus’ main arguments for this thesis (in Ennead 3.6) all rely upon the controversial assumption that the properties prime matter underlies are not properties of prime matter itself. It is then argued that prime matter’s privation of sensible qualities has its conceptual basis in an idiosyncratic understanding of form-matter composition generally, and its primary doctrinal basis in Aristotle’s critical reports (...) on the Platonists’ substratum in Physics 1.9. While Plotinus finds Platonic authority for unaffectible matter in the Receptacle passage of the Timaeus, it is Aristotle’s testimony that provides the crucial impetus for reading that text in this way. On this basis, Plotinus develops a Platonist conception of form’s inherence in matter with distinctively non-Aristotelian features. (shrink)

Plotinus maintains that there is a single first principle, the One (or the Good), from which all other things derive. He is usually thought to hold this view on the grounds that any other thing’s existence depends on its participation in a paradigm of unity. This paper argues that Plotinus has a further, independent argument for adopting a single first principle, according to which principle pluralism is committed (unacceptably) to attributing good cosmic states of affairs to chance. This argument exhibits (...) similarities to ancient design arguments, but is used to draw the more radical conclusion that there is only one non-derivative existent. (shrink)

In developing his theory of aether in De Caelo 1, Aristotle argues, in DC 1.4, that one circular motion cannot be contrary to another. In this paper, I discuss how Aristotle can maintain this position and accept the existence of celestial spheres that rotate in contrary directions, as he does in his revision of the Eudoxan theory in Metaphysics 12.8.

In this paper, we argue that Plotinus denies deliberative forethought about the physical cosmos to the demiurge on the basis of certain basic and widely shared Platonic and Aristotelian assumptions about the character of divine thought. We then discuss how Plotinus can nonetheless maintain that the cosmos is «providentially» ordered. -/- [Note: This paper is a French translation (prepared by Mathilde Brémond) of a paper that appears in A. Marmodoro and B. Prince (eds.), Causation and Creation in Late Antiquity (Cambridge, (...) 2015).]. (shrink)