Mind-body problems are persistent problems understanding how thought, feeling, perception, and other mental phenomena fit into the natural world described by our best science. Hylomorphists take mind-body problems to be symptomatic of a worldview that rejects Hylomorphic Structure.
Hylomorphic structure carves out distinctive individuals from the otherwise undifferentiated sea of matter and energy described by physics, and it confers on those individuals distinctive powers. If Hylomorphic Structure exists, then the physical universe is punctuated with pockets of organized change and stability—composite physical objects (paradigmatically living things) whose structures confer on them powers that distinguish what they can do from what unstructured materials can do. If those powers include the abilities to think, feel, perceive, and act, then hylomorphic structure provides a way of locating mind in a physical world: if structure is uncontroversially part of the physical world, and mental phenomena are species of structural phenomena, then they must be uncontroversially part of the physical world as well.
A worldview that rejects hylomorphic structure, by contrast, is a worldview that lacks a basic principle which distinguishes the parts of the physical universe that can think, feel, and perceive from those that can’t, and without a basic principle that carves out zones with distinctive powers, the existence of those powers in the natural world can start to look inexplicable and mysterious.
If there is nothing built into the basic fabric of the universe that explains why Zone A has powers that Zone B lacks—if nothing explains why you, say, have the power to think, feel, and perceive, while the materials surrounding you do not, then the options for understanding the existence of those powers in the natural world become constrained: either those powers must be identified with the powers of physical materials taken by themselves or in combination (as panpsychists and many physicalists claim), or their existence must be taken as an inexplicable matter of fact (as many emergentists and epiphenomenalists claim), or their existence in the natural world must be denied altogether (as substance dualists and eliminative physicalists claim).
If there is hylomorphic structure, however, the options are no longer constrained in the foregoing way. Distinctive powers like yours and mine exist in the natural world because structure exists in the natural world. Moreover, because structure is a basic principle on the hylomorphic view, this does not simply push the demand for an explanation back a step.
A framework’s basic principles stand in need of no further explanation within that framework. Structure and things that get structured are both basic on the hylomorphic view. Nothing must explain why the former exists any more than something must explain why the latter does. As a result, the view leaves it unmysterious why and how mental phenomena exist in the natural world. Someone is free to reject the hylomorphic framework wholesale—to deny there is such a thing as hylomorphic structure, but if one accepts the framework, there is no way for the problem to arise. In addition, hylomorphism’s ability to solve the problems that beleaguer its competitors is itself something that weighs in its favor.
The key to understanding the hylomorphic approach to mind-body problems is the notion of an activity-making structure. The structures mentioned above are structures that make individuals the unified wholes they are; they are individual-making structures, the kinds of things traditional hylomorphists called ‘substantial forms’. But individual-making structures are not the only structures that exist. The activities in which structured individuals engage have structures as well; these are activity-making structures.
The idea that there are activity-making structures is based on the observation that the activities of structured individuals involve coordinated manifestations of the powers of their parts. When we walk, talk, sing, dance, reach, grasp, and engage in the various other activities we do, we are imposing an order on the ways our parts manifest their powers. On the hylomorphic view, these structured manifestations of powers include thinking, feeling, and perceiving. These activities, like the ones just mentioned, are essentially embodied in the physiological mechanisms that compose us, yet it is not possible to reduce descriptions and explanations of them to descriptions and explanations of physiological mechanisms. The reason is that there is more to these activities on the hylomorphic view than the operations of physiological mechanisms; there is also the way those operations are coordinated or structured, and structure in general is something different from things that are structured. Structure is what unifies simpler lower-level entities and occurrences into more complex ones. Higher-level biological, psychological, and other structures are what delineate the subject-matters of special sciences such as biology and psychology, and what secure the autonomy those sciences enjoy.
The kind of hylomorphic theory I defend in Structure and the Metaphysics of Mind (Oxford University Press 2016) is thus antireductive and naturalistic, but since it rejects both physicalism and some of the central tenets of emergentism it makes a unique contribution to the ongoing effort to articulate an acceptable nonreductive naturalism. It is nevertheless similar enough in its outlines to these more familiar theories that their exponents are likely to see in hylomorphism a congenial alternative or a worthy competitor.
Hylomorphism also has unique resources for solving the problems that beleaguer competing theories; these include the problem of emergence, the problem of downward causation, and the problem of other minds. I’ll describe the hylomorphic solution to the problem of downward causation in a later post.