Jaworski’s thesis is that hylomorphism (understood as the proposition that structure is a real, ineliminable, and irreducible explanatory factor in nature) can supply a novel and uniquely appealing account of the mind-body relation that is both broadly naturalistic and anti-reductionist. He has defended this view in past publications, but here the case is fleshed out in greater depth insofar as it is situated within a comprehensive background ontology.
After a concise introduction, Jaworski spends Chapter 1 providing a preliminary clarification of ‘structure’: it is a form (or arrangement or configuration) of physical materials, the presence of which results in a distinguishable individual belonging to a determinate natural kind with new causal powers. He provides several clarifying illustrations, the first of which is vivid: say you were to take a normal human and put him in a specially sealed bag, then drop a multi-ton weight on him. Afterwards, all the same materials will be present (not a single molecule escaped the bag), but the human will be gone, because what made him human (a member of a distinct kind with defining causal powers) was not the materials alone but the specific way they were structured.
In Chapter 2, Jaworski lays out and defends a substance ontology similar to that of David Armstrong, but where sparse properties are understood as tropes rather than immanent universals, and where states of affairs (or ‘events’ on Jaworski’s terminology) are reducible to particulars-with-tropes. In Chapter 3, Jaworski provides further justification of the trope theory.
Chapter 4 consists of an explication and defence of a version of dispositionalism known as ‘identity theory,’ according to which a single trope can and usually does play multiple theoretical roles. These correspond both to what is normally conceived of as causal powers and to what is conceived of as categorical properties. For instance, the hardness of a diamond is literally identical to its molecular structure, though the relevant trope is conceived differently when thought of in the first way versus the second. Chapter 5 serves as a further defence of the theory, by way of attacking prominent rival accounts—both the categoricalism of figures like Armstrong, and rival versions of dispositionalism like that of Brian Ellis.
Having laid out the background metaphysics, Jaworski proceeds in Chapter 6 to a further explication of structure: a structure is a trope, and like any trope can be counted as a causal power—in this case, a power whose manifestation consists in the configuration of physical parts. This power is necessarily constantly manifesting as long as the individual exists, since a thing’s hylomorphic structure is essential to it. This conception distinguishes Jaworski’s version of hylomorphism from that of other recent theorists like Kit Fine and Mark Johnston, since they “conceive of hylomorphic structures as relations among something’s parts. I conceive of them rather as relations between wholes and their parts: a whole configures or structures its parts” (96). Jaworski also argues that hylomorphism entails emergentism, as the structured individual will have novel causal powers. Living organisms are the paradigms of structured individuals, though he is open to the idea that they can also be found in the inanimate realm. Scholastics will take a special interest in a section of this chapter where Jaworski explains differences between his account and that of Thomistic hylomorphism, in particular critiquing the work of David Oderberg. In Chapter 7, Jaworski further defends his account of structure in the face of standard puzzles involving composition, and in Chapter 8 extends it, building on his model of structured individuals a further ontology of structured activities.
In Chapter 9, Jaworski argues that a hylomorphically structured individual strongly supervenes on its component physical materials, and in Chapter 10 that this needn’t imply that the components wholly explain the range of powers possessed by the individual. That is, the strong supervenience of an individual on its parts does not entail the falsity of emergentism.
Jaworski devotes Chapters 11 and 12 to clarifying the nature of a central competing theory, physicalism, and to refuting Bernard Williams’ charge that hylomorphism is a closet version of that theory.
Chapters 13 and 14 are the heart of the book. Here Jaworski argues that hylomorphism carries major advantages over other philosophies of mind, while avoiding many of their problems. For instance, unlike alternative emergentist theories, hylomorphism faces no problem explaining how mental phenomena are generated by the interactions of lower-level systems (and ultimately fundamental particles). “The reason is that hylomorphism denies that emergent properties are generated or produced by lower-level processes or states. According to hylomorphists, higher-level phenomena are ways in which lower-level occurrences are structured, and structures in general are not generated or produced by the things they structure” (277). Structure is a basic explanatory principle, one whose powers supervene on the activities of lower-level parts but are not explained by them. The human organism is thus a structured individual whose higher-level activities (like consciousness) are the manifestation of emergent powers, powers whose presence is explained principally by the organism’s structure rather than its constituent parts.
Jaworski’s book is eminently clear and well-argued. He develops a genuinely novel account of the mind (and a novel version of hylomorphism) that merits wide discussion. Of course, his strategy of situating the theory within a detailed background metaphysics is risky—the more detailed the background, the more potential ammunition for objections. Personally I find myself unable to accept Jaworski’s account in part because of its commitment to the identity theory of dispositions, which, despite his able defence, I find deeply problematic. Still, I suspect that this sort of strategy carries the only realistic hope of making progress in the largely deadlocked philosophy of mind literature.
