Plato's Natural Philosophy (review)

This major study of the philosophy of the Timaeus—provided with excellent argumentation, a fine bibliography, and useful indices—is of wider significance to the interpretation of Plato than might initially be expected. Most obviously, it takes the dialogical unit as the Timaeus-Critias, as the majority do today. It does not interpret Critias's Atlantis story as such, for this "natural philosophy" is that expounded in Timaeus's monologue, but the Critias is important to chapters 1, 2, and 9, and the groundwork is laid for a better understanding of this too. Chapter 9 ("Dialogue and Dialectic") is also important for the question of why Plato has chosen to let Timaeus expound his theory in a monologue—a question helpful for the understanding of the presentation of ideas in other late dialogues.

Chapter 1 argues that teleology provides the link between Atlantis and cosmology—human activity and divine craftsmanship both being oriented towards the good (unless, like the Atlantids, we err against nature). The idea is worth pursuing, though it runs counter to the presentation of the story as illustrating the virtue of ancient Athenians, rather than the unnatural pleonexia of the Atlantids. Chapter 2 discusses the status of the Atlantis story as history or fiction (not in fact the question occupying the minds of ancient commentators, as assumed [24], which was whether it should be read according to its simple meaning or an allegorical one). Johansen opts for fiction, but with a new and interesting twist: he argues that the attribution to the Egyptians, together with the facts that the events preceded by at least a millennium the Egyptian writings, is itself a warning not to take it seriously as history (39–43).

Chapter 3 explains why Plato qualifies the cosmological account as "likely." The explanation is two-pronged: (a) it offers a copy of a model; and (b) this is a generated copy while the model was eternal, so there is an ontological divide between the two. Chapter 4 goes on to argue that the demiurge virtually stands for craftsmanship, creating order in the world whenever disorder is detected (91), and points out that such a "demiurge" need not act according to quasi-personal mental states, so that the extent to which this is "intentional teleology" rather than "natural teleology" is minimized (86).

Chapter 5 rightly sees Necessity in the Timaeus as something which may or may not be persuaded by reason. While having bodily connections of some sort, it is not the disorderly motion of the Receptacle, which precedes Necessity (as does the creation of the simple bodies [95–99]). Hence it is a feature of an ordered world, and works as a sunaition once it is persuaded, assisting intelligent creation. Its cooperation results from persuasion as opposed to force, but its susceptibility to persuasion does not, for Johansen, turn it into a quasi-personal force. He sees its voluntary submission as an indication that the motions involved in its cooperation were always natural to it, though better than they might have been (100). Necessity is connected with the materials available to the Craftsman, who must select his materials according to the properties that they naturally have—materials with a rational structure affording them the capacity for rational manipulation. This is a complex and rewarding chapter. It passes well beyond what is explicit in the text, but it appeals to much that seems implicit in the methodology.

Chapter 6, on space and motion, pays careful attention to Plato's terminology of place, and evaluates Aristotle's reading of Platonic theory on this topic. Chapter 7 moves on to the Timaeus's version of the tri-partition of the soul, beginning with the cosmic soul that provides the basis for the human version, and explaining how the lower parts of the soul are added in the course of the divine teleological operations. The lesser gods "create man as a teleologically ordered system in which the motions that arise by simple necessity and rational motions are combined...