Another problem with hylomorphic dualism

  1. Human is made of physical matter and spiritual (non-physical) soul united with each other
  2. From (1) we can deduce that any mental process accompanies a neural process
  3. From (2) we can deduce that any neural process can be divided into physical and spiritual process
  4. Neural process is observable process
  5. We know physical process
  6. From (3), (4) and (5) we can deduce that spiritual process is also observable in physical world
  7. What is observable directly or indirectly in physical world is physical too
  8. Form (7) we can deduce that soul is physical
  9. (1) and (8) contradict each other hence hylomorphic dualism is wrong

A number of things confuse me about this.

First, I think that (1) is true on certain construals. A human is a material substance the form (soul) of which is immaterial in a stronger sense than most forms. But the soul is not itself a substance, so there are not two substances united together.

Does (2) mean that for every mental process, there is an accompanying neural process? I don’t think (2) follows from (1) for two reasons. A tenet of hylomorphic dualism is that some bodily operations (intellection) do not require anything physical. In the general case, such operations will rely on objects obtained through the senses, but hylomorphists hold that after death (for example) humans might engage in intellectual activity that is non-bodily. So some mental processes are not accompanied by neural processes.

The next reason is related to the purported inference from (2) to (3). (2) presupposes the division that (3) discloses, but I think you would only get that from (1) if you are interpreting (1) more in terms of substance dualism than hylomorphism. The point of hylomorphism is that mental acts are instances of formal causation, while many neural processes, acts, willings, etc. will be instances of efficient causation. For that reason, the “accompanying” in two would have to be construed as the accompanying of certain cases of formal causation by efficient causes (as I’ve said, this couldn’t be said of all mental acts). But that doesn’t entail the divisibility of (3).

(Compare cases of efficient and formal causation in other substances, even non-living ones. They can’t be divided. This criticism seems to apply more to epiphenomenalist forms of dualism more than hylomorphism.)

Consequently the rest of the argument doesn’t follow. (There are other things I would qualify, but I won’t bother.)

We cannot indeed deduce 2 from 1 nor 3 from 2. We cannot deduce 6 from 3, 4, and 5. We cannot deduce 8 from 7 because we cannot observe our soul in the physical world.

God Bless you :slight_smile:

Ps. I have no idea what hylomorphic dualism is.:smiley:

I had to look it up.

OP seems to like to attempt to provoke discussions in such a way as to show off his erudition. I don’t have a dawg in this particular fight, so I’m going to butt out now.

The argument seems misconstructed at a number of places.

It is not clear that 2) is even demonstrable, let alone likely to be true. How could it be shown that every mental process has a corresponding neural one without assuming that neural processes have a one to one correspondence to mental processes? There are a number of philosophers of mind who would take exception to this based upon the hard problem of consciousness itself - that consciousness has no demonstrable physical basis.

  1. seems just plainly false depending upon what “spiritual process” means and how a “spiritual” process would even be distinguishable from a “physical” one without presuming some kind of reductionism, which is the presumption which essentially leads to the conclusion 9) that if something is observable it can’t be spiritual.

A great deal of text would have been saved with a simple assertion that only the observable (physical) can exist, an assertion that is contentious, at best.

More complete and accurate depictions of hylemorphism can be found here:
and here:

What is the differences here: “substance dualism, the version associated with Plato and Descartes; property dualism, associated with the likes of John Locke, David Chalmers, and (the early) Frank Jackson; and the hylemorphic dualism”?

As Feser points out in Was Aquinas a Dualist? the term hylemorphic dualism was possibly first coined by David Oderberg in Real Essentialism. Feser’s blog also explains in something like laymen’s terms the distinction between the kinds of dualism that arises from any conception of materialism as mechanistic in nature and the more “unified” version of dualism that Aquinas seems to be committed to.

Feser also takes up the question of the different versions of dualism and where Aquinas “fits” given his metaphysics.

The links Peter Plato has given are good.

In brief:

In substance dualism, the body and the mind (or soul) are two distinct substances (basically independent entities, though what a substance is will depend on whose theory you are talking about), the mind being immaterial.

In property dualism, there is just one sort of thing: matter construed physically. But matter can have two sorts of properties: straightforward physical ones as well as mental.

In hylomorphic dualism, the soul is the substantial form of the body in the sense that substantial forms are understood in Aristotelianism/Thomism. For that reason, it’s a bit improper to talk about the “body” as though it is distinguishable from the soul. All substances (even nonliving ones) are hylomorphic (matter-form) compounds; the human substance is just a specific case. A form specifies not just things like shape but the characteristic activities of the substance. So the human soul accounts for the intellective activities as well as the basic material activities of humans (ie. digestion or even nonliving dispositions associated with being material, like mass); there is no presumption that a form is anything special. But, it is claimed, the intellective activities of the soul do not require matter, so the human soul subsists unlike other forms and souls. (Whether this last move has been sufficiently argued for is actually pretty widely disputed in the literature.) (Another benefit of hylomorphism that is tough to articulate in a short space is its causal pluralism; hylomorphists employ formal, efficient, final, and material causes, all of which play into philosophy of mind, whereas most contemporary theories just admit something resembling efficient causality. This allows hylomorphic dualism to address a number of problems; it does not face an interaction problem, as does substance dualism, and it does not relegate the mental to the epiphenomenal, as arguably even most materialisms do. I’d argue that they also are what make possible an explanation of libertarian free will, though that is a very complex issue.)

Substance and property dualism (as a general rule of thumb) take “qualia” and consciousness (and maybe intentionality) as the characteristic marks of the mental, whereas hylomorphism takes intellection and abstract, general thought as what is distinctively human and resistant to material explanation. (However, hylomorphists are more likely to allow finality, which resembles intentionality, in their general metaphysics, so they would likely admit a difficulty for materialism there.)

Aquinas’s philosophy of mind has been interpreted in a few different ways. Feser and Oderberg have spearheaded hylomorphic dualism in the last decade, and I think it’s the most plausible reading. A related subject of dispute is whether Aquinas’s philosophy of mind should be construed as a dualism (Jim Madden, for example, just calls it hylomorphism, but his theory is pretty close to Feser and Oderberg’s). Some others have considered it to be a non-Cartesian substance dualism, construing the form as a sort of substance. (One can work such a theory out so that it is basically equivalent to hylomorphic dualism, or it could be somewhat different. However I think that categorization has more to do with philosophers simply not deciding to create a separate designation.)

William Jaworski has also defended something called “hylomorphism.” He is a Catholic philosopher, I believe, but he mostly defends it as a stronger form of emergentism with the benefits of causal pluralism; he tends not to defend the more historically characteristic features of the theory, like the immateriality of the intellect. This may simply be the context of his defense, though.

That I was aware of it. The soul in fact plays the role form in body.

Intellect does have physical manifestation, all thing human invented such as tools, etc. Hence there must be a relation between spiritual process such as intellect and neural process otherwise intellect could not have physical manifestation. Hence (2) follows from (1).

We know physical matter well (particle physics) and we know the behavior of matter given its constitutes in different forms (condensed matter physics), lets call it physical form such as rock, glasses, water etc. We distinguish between physical form a rock and spiritual form a body. That means there exist some behavior such as intellect that can not be derived from physical form otherwise we didn’t need to assume the existence of spiritual form. Hence (3) follows from (2).

That is exactly what you are doing now. This means that there should exist a one to one map between your intellect and neural process otherwise you couldn’t write what was in your mind and I couldn’t comprehend you.

Consider the case of intellect, what you are doing right now as a spiritual process. We can understand the behavior of matter in different form in term of its constitutes and form, lets call it physical form. We clearly distinguish between physical form a rock and spiritual form body hence there should exist some behavior in which it could not be explicable in term of physical form only such as intellect, consciousness, etc other wise we didn’t need to invent hylemorphism. In the previous comment we learn that there should exist a one to one map between neural process and spiritual process otherwise spiritual process could not have any physical manifestation hence we are dealing with three solid arguments: 1) Physical process are different from spiritual one, 2) there exist a relation between neural process and spiritual process, 3) Spiritual process then become observable knowing physical process.

There is no denying that some kind of “interface” exists between mental processes and physical ones. The problem is that there is no certainty that this interface requires a direct one to one mapping where every mental event has a corresponding neural one and vice versa. In fact, there are varying events, mental or otherwise that trigger the same physical, observable manifestation, such as anxiety and poor digestion bringing on a stomach ache as the observable result, so a strictly one to one correspondence is ruled out on that count.

Furthermore, how could we possibly know that every mental event DOES have a neural component? Experimentally, it could be that a plethora of mental events could be occurring both consciously and subconsciously that are unreported by the subjects because these are only vaguely or quickly available to the conscious subject. How could any experiment that relies on a subject’s complete and unfailing awareness of mental events be a reliable reporting source? How would we know with anything like experimental certainty that every mental process was entering the person’s conscious awareness let alone being reported?

I know on a moment by moment basis that many elusive mental events occur to me but of which I am only obliquely or fleetingly aware. I am certain these would not be reported in an experiment because of their frequency and short lifespan.

Scientists can’t figure out the mysteries of the brain because they refuse to allow for the presence of a spiritual component existing conterminously with the neurons, the material component. The presence of a spiritual component provides animals with a dual memory: a material memory located in the neuronal circuitry of the brain and a “perceptual” memory located in the spiritual substance called nous. The perceptual memory stores qualia, feelings, emotions, meanings, concepts, and percepts, all of which have a “continuous” nature. Neurons, on the other hand have a “discrete” (individual units) nature. Specific neuronal circuits activate specific areas of the perceptual memory to induce sentient experiences. This phenomena is present in all animals in an increasingly comprehensive way from lowest animal forms to the highest, the human. Sentient experience is the source of most, but not all, of animal behavior. It is manifested as mental activities such as awareness, focus, recognizance, perception and response.

At the top of the animal hierarchy, humans are distinct from all the rest as the result of the human brain’s language capability, namely, neuronal circuit’s that are organized to respond to symbols (words, notes, and numbers). The language capability of the brain (the material) combines with the perceptual memory of the nous (the spiritual) to form what we call the “mind”. Only humans have minds because only humans have language. We (at least I) do not think without symbols. Thought allows us humans to reflect, contemplate, analyze, conceptualize, create, and rationalize. Because we have a mind and can think, we are the only animal with a soul.

The soul is the form of the nous. Form not in the sense of geometry, but form in the sense of response. The soul is how the perceptual memory “sees” the world, with what emotions, and feelings the perceptional memory responds either to a perception or an action. For example. the soul can be informed to experience joy from giving or making sacrifices. We Catholics believe the response of joy to giving is provided through actual grace. Grace does not act spontaneously; it must be pursued through the mind’s rational search. It is thought, the substance of free will, that informs the soul. It is an ongoing process.

Of course, the mystery of the brain is far more complex than the outline that I’ve just presented. However the mystery can be unraveled in the form of a plausible explanation developed through the use of reason, but not without the premise of hylomorphic duality.

Sandcastles that we make at the beach, that can only be made with wet sand, are an analog for hylomorphism. Water allows the sand to be formed and sand allows the water to be formed just as the soul informs the body and the body informs the soul. Not a perfect analog, but close enough to convey the idea of hylomorphism.


There should be a one to one map between mental and physical at least within hylomorphic dualism since soul is form of matter.

I am not clear that this accurately describes hylemorphism in a way Aquinas or Feser would accept. The problem with "existing conterminously” is that it seems to imply that some kind of spatiality and chronology are an aspect of the “spiritual component.”

The other issue is one of Esse or Existence. If God’s essence is “to Exist,” also described by Aquinas as Actus Purus (Pure Act) then it becomes unclear, I think, to posit another “substance” (Nous) that exists alongside matter and conterminous with it. This becomes particularly apparent when Nous is, at times, used to refer to the Mind of God. That would seem to entail some kind of distinction between Nous and Existence as if Existence could be a kind of “property” of Nous as it is of matter - Nous, like matter, may or may not “have” existence at a particular time and place - but then what is it that endows existence onto this distinct “substance” at different times and places to varying degrees?

I think Aquinas viewed Being or Existence as Act. That God is Existence or “The Act of To Be” Itself (Ipsum Esse Subsistens), all else “exists” as an aspect of its “whatness” or “form” (degree of actuality) imparted by God (Being) to it as an act of creation. Material existence describes more the degree to which something exists - along the range of potential to actual - rather than a “kind” of existence. Why would an additional “substance” like Nous be required by Aquinas?

In some ways I suspect calling hylemorphism a “dualism” might be misleading at some level because of the connotation it has to matter as a distinct “substance,” which I don’t think Aquinas ever intended because Prime Matter, for Aquinas, is non-existent.

But hey, I could be wrong, feel free to show where :nerd:

Only if a kind of Cartesian dualism is assumed.

Form is what imparts existence of a particular “nature,” i.e., material, onto human beings. Matter isn’t subsistent as a “substance” upon which a separate “substance” called soul impresses a “form,” like a seal (soul) onto wax (matter.). That is a distinctively Cartesian view.

Hylemorphism, as far as I understand, implies that God (Pure Act) creates a subsisting form which has a physical nature or “whatness” but is not restricted to that nature. It could essentially subsist in another form (or forms) if God so chose. The human form is extensible in the sense that it essentially presents material or physical attributes, but is not restricted to these by its intrinsic nature. For Aquinas, plant and animal forms, just as, say, rocks and water, are fully exhibited as material existents (they have properties broadly defined as physical or material,) but human forms are more “open-ended” in that even though they are properly described as physical, they have a capacity for taking on a supra-material nature beyond the physical one that fully capacitates their current earthly existence. Human beings are properly called physical beings but have a kind of "open architecture” whereby their form can be extended beyond the physical.

This is demonstrated, for example, by Christ, who did have a human nature but also the divine nature. It is also demonstrated by the human intellectual capacity to apprehend universals or abstractions as part of the process of knowing.

Premise 6 doesn’t necessarily follow. In fact, the very nature of spiritual matter means it *cannot *be observable in the physical world. You need to somehow prove this premise before you can use it in this argument.

You haven’t established why this is the case. At worst, you’ve shown that substance dualism would require a one-to-one mapping between mental and neural activities. Intentionality seems to disprove your thesis that there’s a one-to-one mapping between mental and neural processes. We all are able to intend general, universal concepts that are determinate from a mental point of view. But the underlying neurological physical representation of said general concept must be indeterminate in what concept it intends because the matter is particular and the concept is general.

Any mental activity is related to a form hence there is a one to one map between mental activity and neural activity.

(6) does follow from the fact (3), (4) and (5). Consider a mental process M that can be divided into physical process P and spiritual process S. M can be measured since it is related to neural process. We know what to expect from a physical process in a neural system hence we know P. What is left is S that can be calculated by knowledge of P and M.

  1. Soul is form of body
  2. Any mental activity has a form
  3. From (1) and (2) we can deduce that any mental activity must have a manifestation in body
  4. Intention is a mental activity
  5. Intention has a manifestation in body, minimally as neural activity
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