Can Matter Think?

Jesus raising the daughter of Jairus

“He who planted the ear, does he not hear? He who formed the eye, does he not see?”

Psalm 94:9

You are having an experience right now — the look of these letters, the feel of attention, the silent voice reading along — and that plain fact is the hardest problem in the materialist’s world. Every physical fact about your brain can be stated in the third person: neurons, voltages, chemistry, maps of activation. But the one thing you know most directly — what it is like to be you — appears in none of those descriptions, and no one has ever explained how it could. Science has learned magnificently what the brain does while you experience. What experience is, and why there should be any at all in a world of particles, remains exactly where it was.

The skeptic answers that the mind is simply what the brain does — that the correlations run so deep, and the dependence is so total, that the soul has nowhere left to hide. This page takes that case seriously, states it at full strength, and then asks the three questions it never manages to reach: why any physical process is about anything; why the felt quality of experience resists every functional story told about it; and why, if thinking is only chemistry obeying physics, the thoughts that say so should be trusted.

The Catholic answer, for the record, is not a ghost in a machine. The Church’s ancient account — the soul as the form of the body — expects the brain-dependence the skeptic cites, and explains the two or three things no arrangement of matter has explained. That, too, is the business of the panels below.

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Atheist/Skeptic View

Jump to the Catholic View ↓

The skeptic’s position is that the mind is what the brain does — not a tenant of the body but an activity of it — and that the evidence for this is now as strong as evidence in science gets.

The Dependence Is Total

Everything mental tracks something neural. Damage the visual cortex and sight goes; damage the hippocampus and new memories cannot form; damage the frontal lobes and — as the famous case of Phineas Gage first showed — the personality itself changes. Alcohol, anesthesia, dementia, and a blow to the head all do to the “soul” exactly what they should not be able to do if it were an immaterial thing merely using the brain. Nothing mental has ever been observed to survive the loss of its neural substrate. The simplest reading of a correlation that complete is identity: the mind does not ride in the brain; it is the brain, working.1

Dualism Cannot Say How

The traditional alternative — an immaterial soul interacting with the body — has never answered the question Princess Elisabeth put to Descartes in 1643: how does a thing with no mass, charge, or location push matter? Every physical event in the brain has, so far as measurement can tell, a physical cause; there is no gap in the neural accounting where a soul’s influence could enter without violating the conservation laws. An entity that does no detectable work is indistinguishable from an entity that is not there, and Ockham’s razor retires it.2

Mind Comes in Degrees, and Can Be Built

Nature shows consciousness arriving gradually — nervous systems shading from worm to crow to chimpanzee to child — which is what an evolved capacity looks like and not what an all-or-nothing soul looks like. And the capacities once called distinctively mental are falling to engineering: machines now use language, prove theorems, and recognize faces. Whatever intelligence is, it is evidently the kind of thing organized matter can do. The residue called “experience” will go the way of élan vital — a mystery of organization mistaken for a mystery of substance, dissolved by understanding rather than answered by it.3

The Soul of the Gaps

The history of the soul, the skeptic concludes, is the history of a retreat: once it explained life, growth, sensation, and thought; biology took life, physiology took sensation, and cognitive science is taking thought. The soul now shelters in whatever the current science has not yet reached — today, the feel of experience. A hypothesis that survives only by moving is not surviving; it is being escorted off the premises.4

Endnotes
  1. The dependence argument is pressed throughout the physicalist literature; accessible statements in Patricia Churchland, Touching a Nerve (Norton, 2013), and Daniel Dennett, Consciousness Explained (Little, Brown, 1991). ↩
  2. Elisabeth of Bohemia to Descartes, May 1643, in their correspondence; the causal-closure argument is standard in contemporary philosophy of mind. ↩
  3. On graded animal cognition and the engineering of intelligence, see the general cognitive-science literature; the élan vital comparison is Dennett’s. ↩
  4. The “retreat” framing parallels the god-of-the-gaps charge examined on this site’s science page. ↩

Catholic View

Grant the dependence first, and grant it whole. The correlations are real, the lesion studies are real, and a Catholic loses nothing by them — because the Church’s account of the soul was never the ghost the skeptic is refuting. But before the alternatives are compared, the explanandum should be stated honestly, and it is bigger than the left panel lets on. Three things need explaining, and the brain-does-it story explains none of them.

The Hard Problem Is Not a Gap

Neuroscience explains functions: discrimination, reaction, report, control. What it does not touch — what David Chalmers named the “hard problem” precisely to distinguish it from every solvable one — is why any of that functioning is accompanied by experience: why there is something it is like to see red, rather than mere registration in the dark. This is not a missing mechanism awaiting a finer scanner; it is a difference in kind between every third-person fact and the one first-person fact. A complete physical description of your brain would let an alien predict your every word — and leave it unable to tell whether anyone was home. The élan vital comparison fails at exactly this point: life was a set of functions, and functions yield to mechanism; consciousness is what remains after all the functions are accounted for.1

Aboutness, and the Mill

Second: thoughts are about things. This sentence is about the mind; a thought can be about Vienna, or the number seven, or something false, or something that does not exist. No physical state, described physically, is about anything — one neural configuration no more refers to Vienna than a rock refers to the sun that warms it. Leibniz saw the difficulty three centuries ago: walk into the brain as into a mill, he said, and you will find parts pushing parts, and nowhere anything that explains a perception. Enlarging the mill or wiring it finer adds more pushing. Meaning, reference, truth and falsehood — the entire currency of the mind — are not properties any arrangement of matter possesses simply as matter. They must be smuggled in by an interpreter; and the interpreter is the thing to be explained.2

The Argument That Saws Its Own Branch

Third: reason. If every mental event is fully fixed by prior physical causes, then the skeptic’s conclusion was produced the way a kidney produces urine — by chemistry, not by logic. Causes are not reasons: a calculator’s output is caused, and it counts as arithmetic only because minds built and read it. The materialist asks us to believe that blind physical causation assembled, in him, a device whose outputs track truth about metaphysics — while denying the only kind of agency that could make an output answerable to truth at all. Darwin’s own “horrid doubt” about the convictions of an evolved mind is examined on the evolution page; here it is enough to say that an argument for materialism, if materialism is true, is not an argument. It is a secretion.3

The Option the Objection Skips: Soul as Form

The left panel refutes Descartes and thinks it has refuted the soul. But the Catholic doctrine is older than Descartes and different in kind. The Catechism states it in a sentence the skeptic could almost sign: “The unity of soul and body is so profound that one has to consider the soul to be the ‘form’ of the body” — spirit and matter in man “are not two natures united, but rather their union forms a single nature.” On this hylomorphic account there is no ghost pushing neurons and no interaction problem, because the soul is not a second thing alongside the body; it is what makes this matter a living, seeing, thinking man — as the shape of a statue is not a part beside the bronze. Of course damage to the instrument garbles the music; total dependence of mental function on brain is exactly what the doctrine predicts. What the doctrine adds is an argument the mill cannot digest: the intellect’s grasp of universals — of triangle-as-such, of justice, of truth — is an operation no bodily organ performs, since every organ’s state is particular; and a power with an immaterial operation cannot be wholly the act of a material organ. That, not a phantom, is why the Church holds each soul to be directly created and able to survive the body it informs — incomplete without it, awaiting the resurrection Christianity actually preaches, of the body.4

Who Retreated?

So the “soul of the gaps” history is backwards. The Church never taught that the soul explains digestion or the weather; Aquinas assigned to bodily organs everything bodily organs do, seven centuries before neuroscience, and the tradition’s claims for the soul were always exactly the three the mill still cannot touch: experience, meaning, and reason. Nothing has retreated. The mechanist has spent four hundred years capturing territory the doctrine never claimed, and now stands before the three capitals it always did — armed, by its own account, with nothing but pushing parts. The Psalmist’s question still ends the argument it began: he who planted the ear, does he not hear? A universe that grew hearers and knowers was never a universe of deaf matter. Something in it was minded from the start — which is the conclusion the arguments page reaches by three other roads.5

The full essay walks the case at length: the hard problem stated with Chalmers’ own distinctions, Leibniz’s mill and the problem of aboutness, the argument from reason, hylomorphism against the ghost, and what the Church actually claims for the soul and why. Download it from the summary below — and the comments are open, anonymously if you prefer.

Endnotes
  1. David Chalmers, “Facing Up to the Problem of Consciousness,” Journal of Consciousness Studies 2 (1995), pp. 200–219, which coined the “hard problem”; Thomas Nagel’s classic paper on what it is like to be a bat (Philosophical Review, 1974) makes the first-person point pressed here. ↩
  2. Leibniz, Monadology §17, paraphrased. On intentionality as the mark of the mental, the point descends from Brentano and is conceded on all sides; the dispute is over whether naturalistic accounts succeed. ↩
  3. The argument from reason is developed in C. S. Lewis, Miracles, ch. 3, and in its rigorous form in Alvin Plantinga, Where the Conflict Really Lies (Oxford, 2011), ch. 10. ↩
  4. Catechism of the Catholic Church §365, quoted; §366 on the soul’s direct creation and survival. Aquinas, Summa Theologiae I, q. 75, on the intellect’s immaterial operation; q. 76 on the soul as form. Edward Feser, Philosophy of Mind (Oneworld, 2006), gives an accessible modern presentation of the hylomorphic option. ↩
  5. Psalm 94:9, RSV. The biblical anthropology of soul and resurrection is treated on this site’s What Is the Soul? page. ↩

Summary

Grant the brain-dependence whole — the Catholic doctrine predicted it. Lesions, chemistry, and anesthesia do exactly what the Church’s account expects, because the soul was never a ghost using the brain: it is the form of the body — “spirit and matter, in man, are not two natures united, but rather their union forms a single nature.” Refuting Descartes leaves the older doctrine standing untouched.

Three things remain that pushing parts cannot supply. Experience: every function can be described in the third person, and what it is like to see red appears in none of the descriptions — the hard problem is a difference in kind, not a gap awaiting a finer scanner. Aboutness: no physical state, as physical, refers to Vienna or to anything else; walk through Leibniz’s mill and you find parts pushing parts, and no perception. Reason: if every thought is fixed by chemistry, the argument for materialism was secreted, not concluded — causes are not reasons, and the branch saws itself.

The intellect’s own operation points past the organ. Every bodily state is particular; the mind grasps universals — triangle-as-such, justice, truth. A power with an immaterial operation cannot be wholly the act of a material organ: that argument, not a phantom, is why the Church holds each soul directly created, able to outlast the body it informs, and incomplete until the resurrection of the body.

The retreat story is backwards. The tradition never claimed the soul explained digestion; Aquinas gave the organs their due seven centuries before neuroscience. The mechanist has spent four hundred years taking territory the doctrine never held, and stands now before the three capitals it always claimed — experience, meaning, reason — armed with pushing parts. He who planted the ear, does he not hear?

For a more complete essay on this topic, download Can Matter Think? (.docx) or (.pdf)

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