The Philosophy of the Mind & Catholicism


PS: This is pretty complex. I was wondering what philosophical view the Catholic Church teaches on the mind. Hear me out. I understand that we as Catholics believe in free will but in more philosophically complex language what is that view specifically? Is that a substance dualism or
property dualism? Is there another view specific view on this that better supports the Catholic view? Thanks for your time! (Also PPS: I’m a beginner at philosophy so my apologies for not fully understanding these concepts very well.)


It is hylomorphic dualism.


Thank You very much


There’s not a specific, dogmatic philosophy of the mind, and different Catholoc theologians have different approaches. One of the most influential, traditional Catholic thinkers on philosophy of the mind is Thomas Aquinas. Aquinas did hold to a hylemorphic dualism, but this is neither substance dualism nor property dualism.

The brain plays a huge part in consciousness and the mind, but abstract thought requires an immaterial operation to grasp universals. (This isn’t hylemorphic dualism, by the way, that’s something else, it does connect to his PotM, but it’s not his explanation of PotM). This isn’t a separate immaterial substance united to a material substance, it’s simply an operation that a human does. It’s an Aristotlean view od substances, it’s an Aristotlean view of causation, it’s not limited to a mechanical view of nature like Descartes or other rationalist or modern philosophers took.


This is were i tend to have difficulty with Aquinas, because i view the intellect as a thing in itself operating through the workings of a material object. I don’t see how it’s possible not to view the intellect and the brain as representing an immaterial nature united with a material nature without committing to some kind of monism. I see no middle ground.


Indulge me as I work through a thought, but it might not be entirely unlike how a Thomist would approach radioactive decay, which seemingly has no mechanical trigger to serve as a cause, leading some to say that it lacks a cause altogether (that could certainly be elaborated upon better). However, for the Thomist, that is insufficient to rule out causation, for we take a broader view. If it’s simply in the nature of an isotope to have radioactive decay, then that is a sufficient instrumental cause for there being radioactive decay. The causes of the radioactive decay are the efficient cause of the isotope itself, and its formal cause, and its material cause, and its final cause. Similarly with the immaterial operations of the mind in humans. It’s simply in the nature of the substance of a man to comprehend universals (hence why it’s called a power of the form/soul and not matter, not because the soul is a ghost interacting with the body, but because it defines the substance, and it’s simply in the nature of the substance to do this). We don’t need to be absolutely mechanical about it and identify an interaction between mind and body as a source of causation. The efficient, material, formal, and final causes of the human itself is sufficient explanation for the cause of a human grasping universals.

Now, this is a connection I am making myself just now (I am likely not the first to do so, but I say this just to explain I am not quoting someone formally learned on the topic), and perhaps there are reasons I have not thought of that make them too dissimilar for comparison. I’m due a refresher, though.


Apologies as I am having a bit of a difficulty understanding since I’m just a beginner in philosophy and (judging by your profile) you seem to know a lot about this. What exactly are the different views of the mind that are compatible with Catholicism. I seem to have a difficulty understanding hylomorphic dualism and I don’t know if I accept it. What exactly is it and are there more rational alternatives?


It is simple. Things are made of stuff and stuff is formed. In case of human, form is soul according to Aquinas.


The thing I have a difficulty over is the definition of “form” in Aristotelian/Thomistic philosophy. From what I can gather online the defenition doesn’t seem to be clear to me. What is it in the simplest terms?


Things are made of atoms. Atoms in a thing have specific configuration, so called form.


Thanks, @STT! In the case of humans, is the soul then reducible to the functional and structural relations between all of our physical parts, as this simplest case would suggest? So that our ‘configuration’ is something about what the body allows us to do, including think and feel and so on?


Yes. Aquinas then personifies form in the case of human and call it soul.

Yes. It is shown by science that there is a correlation between neurons activities and thinking and feeling and so on.


Well that’s super interesting! It suggests that the ‘self’, to the degree that the self is identifiable with the soul, isn’t something different from the overall functional/structural relations between (and maybe capacities arising from?) our physical and psychological components. So is hylomorphic dualism in a way viewable as a form of ‘functionalism’ about the soul?


Yes. :slight_smile: :wink:


Hylemorphic dualism is “matter-form” dualism. For any existing material being a distinction can be made between the principles of its form and matter. All human beings share the same form, or pattern. It’s by virtue of this principle that they are all the same type of thing. However, while all human beings are the same type of thing, it’s clear that multiple human beings are not THE same thing (as in, one thing). There’s multiplicity. Why? Because the material and spatial-temporal location makes them different. You could look at this at a more fundamental level, too. All hydrogen atoms are the same type of thing, but one hydrogen atom is not the other hydrogen atom because it’s made up of different matter.

STT mentioned the word “soul.” I don’t think it’s really necessary to go there, as in modern context people conjure up an image of some ghostly substance when they hear the word “soul.” Aquinas simply used the word “soul” when it came to talking about the form of any living thing, not just humans.

As you can see, hylemorphic dualism isn’t a philosophy of the mind theory. However, I did say it tied into Aquinas’ philosophy of the mind. Are you familiar with philosophical realism? There are many different schools, and also many different schools of competing anti-realist philosophies. There are those who may say “humbug” to both but it’s not something one can truly avoid. Anyway, Thomism is a realist philosophy, and holds that “abstract objects” are real. Not that they are physical, mind, but that they are objectively grounded in reality and not simply systems existing only in our heads and not in reality. An example of an abstract object would be a proposition. “Snow is white.” You can repeat that in any number of languages, it’s not the language that matters. The proposition is real. Likewise, 1+1=2. This isn’t just a man-made axiom, it’s an objective truth of reality which we’re using man-made symbols to represent. This applies to other universals as well, such as triangularity, or human beings, or trees. Man can abstract from particular triangles, or particular humans, or particular trees to the universal concept of triangularity, human-ness, and trees. What it means for man to make these abstractions is to grasp the form of a thing in his mind. The form is not a shape or arrangement, it’s simply the principle of what the thing is. It’s the ability to grasp universals that, to Thomists, mark the difference between humans and other animals. It’s what allows us to have real language, to engage in abstract thinking, etc… And this can’t be carried out exclusively by material, for how can material take on the form of a thing? Therefore there must be an incorporeal operation that a human being is able to carry out.

Now, there are reasons Thomists hold that this must be the case, and that materialist philosophies are insufficient to explain the mind and in fact would require denying the mind altogether, if one is consistent about following them through to their conclusions. I haven’t delved into the reason why, it’s a lot of ground to cover, but I wouldn’t be a Thomist if I thought there were more rational alternatives.


If we’re talking about hylemorphic dualism, form is not the shape or arrangement or specific configuration of a thing. It’s simply the principle of what a material thing is. If there are multiple things that are the same type of thing, the common principle they share is their form. What differentiates them is their matter.

You see the two principles thing a lot in Thomism: a principle by which things are the same and a principle by which they are different. Examples being existence and essence, form and matter, potency and act, substance and accidents. Thomists hold that these aren’t just arbitrary distinctions, but that arguments can be made for these being real distinctions.

Edit: Let me also reiterate that the RCC doesn’t teach any one philosophy of the mind as dogma or doctrine. I’m just talking about the Thomist school of thought, named after Saint Thomas Aquinas.


Thank you so much for your good insight and knowledge on this subject. Although if hylomorphic dualism is not a philosophy of mind theory than what examples of philosophy of mind theories would be compatible with Catholicism? And within these views what specifically do YOU think is the most reasonable mind theory?


I would say that it does look like a form of functionalism, but Edward Feser responded to this in his book “Aquinas: A Beginners Guide”. I can’t remember the exact argument, but he basically said it isn’t functionalism. This would be a good book to get an understanding of his work on the soul.


The philosophy of mind most compatible with Catholicism is the philosophy of St. Thomas Aquinas. I don’t know if there is a “philosophically complex term” that people nowadays use to designate St. Thomas’ view. Back in the days when I was doing philosophy, we simply call it “Thomistic Epistemology.”

Very briefly, St. Thomas holds that every human person is a composite of a material body and a spiritual soul. (You can see the dualism right there.) It is by his soul that he knows and understands (intellection), and it is also by his soul that he makes decisions and free choices (volition). Unlike pure spirits (such as the angels), man does not merely use his soul, but also uses his body (his senses and his brain) to gain new knowledge. Because man needs sensory data to form ideas of things. However, the ideas he forms in his intellect are not anywhere close to material images or photographs in the brain. Photographs, being material, are limited to this picture or that picture. Ideas, however, being immaterial, do not have that limitation. My idea of a horse, for example, is not limited to this horse, with this particular color, this particular height, this particular smell, etc. My idea is more like “horse in general.” This is how we know that ideas are produced by something immaterial or spiritual in man – and that is the soul. By means of his soul man can also form ideas that even defy pictorial images, such as our idea of “justice,” “virtue,” “wisdom,” etc. These are conceptions that can only be understood by a spiritual being, or by a composite being (like man) that has a spiritual soul.

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Feser (a Thomist philosopher for those who aren’t familiar) also specifically has a Philosophy of the Mind book which I found interesting. He of course settles on a Thomist position, but he speaks to many different existing theories on the subject.

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