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“Emergence” and the Soul


Philosopher Tim O’Connor at Indiana University has a fine essay that asks, “Do We Have Souls?” He answers in the affirmative, and he provides insightful critiques of materialism and Cartesian dualism.

On Cartesian dualism:

Descartes [argued] a softened variant of Plato’s mind-body dualism. The material world ultimately consists in material particles wholly governed by mechanical laws of motion. The human soul is an immaterial substance, but (departing from Plato) its existence and proper functioning intimately depends, causally, on the healthy functioning of the brain. It is not naturally immortal; if it survives death, it must be a consequence of God’s sustaining it apart from the body. We still have a sharp dualism: bodies large and small generally operate according to principles distinct in kind from those according to which souls/minds do. Their convergence in the human brain has to be taken as a brute given, a contingent connection perhaps established by the power of God. 

Cartesian dualism, which is a crucial philosophical error despite its dualist assertion, is Platonic in nature. What’s wrong with Cartesian dualism is its abandonment of hylemorphic (matter-form) metaphysics. Descartes describes nature as an unnatural blending of two substances — res cogitans, the thinking substance, and res extensa, which is “matter” defined as that which is extended in space. As metaphysics, it is pitiful, and wholly lacks the coherence and elegant explanatory power of Aristotelian hylemorphism.

Materialism, in its modern form, is essentially Cartesian dualism with the res cogitans discarded. Materialists strip nature of all that is intelligible, and struggle unsuccessfully to provide a coherent understanding of the only thing left: matter, understood as mere extension in space.

O’Connor points out that without res cogitans the materialists’ reduction of Cartesian dualism offers merely a

reductive image of “man a machine.” It is essentially Descartes’ picture of reality minus souls. According to it, human persons, no less than inanimate chunks of the physical world, can be entirely understood (in principle) in terms of the interactions of the body’s basic parts. Psychological states that Descartes assigned to the soul are here taken either to be epiphenomenal — having no influence on other psychological states or bodily behavior — or as (somehow) consisting in complex states of the brain.

Many contemporary thinkers follow [materialists] in dismissing philosophical and religious talk of “the soul” as having no place within our ever-growing scientific knowledge concerning the embodied natures of human persons. But insofar as there is more than one notion of the soul, it may be no less misleading to state simply that there “is no such thing as the soul” than it would be to affirm its existence without qualification — one may be taken to deny not only unwanted associations but also others that one embraces or (as I will suggest) should embrace. Let us take a different, rehabilitative tack and use the word “soul” as a placeholder for whatever underlies the constellation of capacities of thought, emotion, and agency that we observe in mature, fully functioning human beings. Then our question shifts from the categorical Do we have souls? to the open-ended What is the nature of “the” soul (or “ensoulment”) and its current and future limits? This way of posing our question invites us to consider answers lying between the extremes offered by Descartes and [materialists].

O’Connor offers an Aristotelian alternative. He notes that materialist philosophers and scientists

have lost sight of the “Aristotelian” alternative. Aristotle’s specific philosophical account of objects as form-matter compounds is no more appealing to many of us than are his antiquated physics and biology. But his broader nonreductionist, nondualistic vision is very much worth developing in contemporary terms. A number of scientists and philosophers attracted to this vision have latched onto the term “emergentism,” and I will follow them here. But we should be careful to note that this term has meant different things to different thinkers. Here I mean a view on which human persons, other sentient animals, and possibly a wider array of complex systems are wholly materially composed while having irreducible and efficacious system-level features. These features are originated and sustained by organizational properties of the systems (in animals, by properly functioning brain and nervous systems) while also having in turn causal influence on components of the system in its evolution over time. That is, emergent systems involve an interplay of “bottom-up” and “top-down” causal factors. While they are not fundamental building blocks of the world in the way that fundamental particles or Descartes’s souls would be, they nonetheless are natural unities, causally basic entities.

O’Connor’s endorsement of a general Aristotelian approach to understanding the mind (soul) is welcome, but I am unsympathetic to the concept of “emergence” as having any value in the debate about the nature of the mind and its relation to the material brain. I don’t believe that “emergence” really represents an Aristotelian or Thomistic view, and emergence is fraught with metaphysical muck.

Emergence is generally taken to mean that higher order complex systems have different properties than we can infer from the lower order components of the systems. A classic example is “wetness” as an emergent property of water molecules. There is nothing in our understanding of H2O at the molecular level that would lead us to predict that billions of H2O molecules in the liquid state would feel “wet” on our fingertip. Wet is not a state described or predicted by quantum mechanics. Yet water certainly does feel wet. According to the emergentists, wetness is thus an emergent property of water molecules.

Emergentists describe the mind in an analogous manner. There is nothing in neurotransmitters or the biochemistry of neurons that would lead us to expect thoughts to emerge. Yet when neural tissue is properly organized, thought emerges. The mind, according to emergentists, is an emergent property of brain matter, just as wetness is an emergent property of water molecules.

There are several problems with this view. First, I don’t believe that it is appropriate to ascribe the concept of emergence to Aristotle. Aristotle was an essentialist: he believed that substances have essences that characterize them as a whole, and that the essence (roughly the composite of matter and form that can be defined) is not reducible to its parts. Aristotle saw essence as fundamental, and essence (the whole) as more real than parts. Emergentists, on the other hand, see the parts as fundamental and most real, and emergent properties (analogous to Aristotle’s essences) as elaborations on the fundamental (molecular) reality. Aristotle saw the fundamental reality as the whole. Emergentists see the fundamental reality as the parts — for the emergentist, the whole emerges from the parts, but is not the fundamental thing.

For materialists, emergence is a sort of get-out-of-jail free card. Materialism, taken seriously, is nonsense. Obviously, the mind cannot be explained wholly by reference to matter extended in space. Mental things share nothing — nothing — in common with matter. Thoughts are intentional (refer to other things), private, dimensionless, massless, not composite, etc. Matter is non-intentional (doesn’t inherently refer to anything else), public, has dimensions and mass, is composite, etc. Obviously, materialism as a metaphysical system has nothing to offer for the understanding of the mind.

Faced with this rather obvious impediment, some materialists invoke emergence. It may be true that matter shares nothing in common with thought, the materialist stammers, but thought emerges from matter. It’s a kind of magic that Houdini would admire. When you have no explanation, just say it happens and that explains it.

Emergence explains nothing. It merely means that the materialist has no explanation whatsoever for the mind, and would rather not dwell on the question.

And there are deeper problems with emergence as a theory of mind and as a metaphysical concept.

First, while it might be (marginally) coherent to invoke emergence to explain wetness and such, it is worth noting that emergence offers no possible explanation for differences in ontology. Water feels wet when touched, but the emergentist is not claiming that water molecules in becoming wet have become a fundamentally different kind of thing. The water molecules haven’t changed. They are still just water molecules, nothing more or less. They just feel wet.

But emergence as applied to the brain and mind, unlike to water and wet, asserts an ontological difference. Emergentists assert that brain tissue becomes a completely different kind of thing — a thinking thing — when the mind magically emerges from matter. As a metaphysical concept, emergence applied to water and the like is tenuous enough. It plainly offers no explanation whatsoever for how a completely different kind of thing — mind — is produced by brain matter. That’s a bridge too far, even for Houdini.

The second problem for emergence as an explanation for the mind can be understood by considering what we mean when we say that a property of a whole emerges from its parts. What we invariably mean when we talk about emergence in the natural world is that the whole is perceptually different from its parts. Water doesn’t really become something different when we take billions of water molecules and put them on our fingertip. It just feels different from what we would have expected, given our knowledge of physics of individual water molecules.

Emergence always refers to a perceptual or intellectual surprise. A property is said to be emergent if we didn’t expect it to be characteristic of a whole based on our understanding of its parts. Emergence is a mental phenomenon. It is a perceptual surprise, not a magical property somehow evoked by adding a lot of little parts together.

Emergence, as a perceptual surprise, can’t explain the mind because emergence presupposes the mind. A genuine explanation can’t presuppose that which it purports to explain.

Emergence as a theory of mind is junk philosophy and junk science. It’s circular reasoning — the “emergent” explanation for the mind-brain relationship boils down to “It’s surprising!” The only reason to invoke emergence is to defend materialism from refutation by reality. It is a tactic, not an explanation. As such, it is a favorite of materialists, who, lacking explanations, are in dire need of tactics.

Image credit: geralt, via Pixabay.