Can a Philosophical Case Be Made for Immaterial Human Intellect?

Recently I have been trying to understand how a logical, rational case can be made for the existence of the immaterial rational human soul, so I was wondering if anyone on this forum has any suggestions for accomplishing this. Intellect, along with will, are two of the proposed functions of the rational soul. Higher order reasoning and willing are usually attributed to more complex neurochemical processes in the human brain. Despite this, I think a case can be made for the existence of the rational soul via an argument for the immateriality of human intellect. The argument is as follows: (source:

Humans are able to think in terms of abstract universal concepts. Consider a simple example (made in the above article): triangularity. Triangularity is a concept that cannot be explained by a materialist paradigm alone. For instance, someone may draw a triangle but this is not sufficient to express triangularity, as an instantiation of triangularity would necessarily have features that the concept lacks (such as a triangle being scalene which is not a feature of triangularity, a 2D shape is also a feature the concept lacks). One may argue that there is a common neurochemical signal that, although difficult to identify, nonetheless exists when a human thinker considers triangularity. But what would the signal be? Everybody reading this post probably is imagining something different. The thinker may not even be thinking of an image, but maybe instead is thinking of the word or the sound of the word. Is the word “triangularity” the commonality? Not really, because is it in English, Spanish, French, Italian, Japanese, Greek, Latin, pig Latin, clingon, some weird language only understood by the thinker? Since the mental imagery or physical sensation is indeterminate, it stands to reason that there is an immaterial component to human intellect that is able to understand these concepts. The universal concept would then be determinate. Once the concept is grasped and understood it cannot mean anything else.

Consider another example where there is no pre-existing human bias. Suppose astronauts land on Mars and discover the following scrawled on the side of a mountain: “&&#(J%^^,@**###$+>><.” It’s obviously the result of an intelligent agent and not random processes but is the preceeding character string sufficient for understanding what it means?

Corrections and criticisms are welcome :slight_smile:

Wouldn’t a logical or scientific case be more to the point?

You can find a philosopher to say anything.


Can there really be a language understood “only by the thinker”? Is it language at all, if not used in communication?


Science has found that our natural heads come equipped with a faculty for number.

It is likely that instead of “triangularity,” we likewise have in our head a descriptor for “spatial triplication,” or equivalent, which once we have learned our shapes in childhood, registers as a triangle.

Consider that it is possible to see a triangle where none exists: the famous optical illusion in which wedges are blanked out of three facing circles, for example. There’s no triangle; the human head sees one anyway.


I think the scientific bias we are seeing against such concepts arises in part because we are naturally and somewhat logically timid in separating - even in thought and even only when applicable - the stuff of reality, so to speak, and how we think about it. I mean, exactly because we abstract universals from things, there is a natural fear that in this process we might divorce ourselves from the source of those abstracted universals and consequently divorce ourselves from the source of our knowledge by a kind of scrambling. I think scientists are right to insist on the “stuff” of reality and consistently point to it and demand concepts be absolutely grounded in it - Aristotle did no less. However, obviously, this only the source or starting point or basis of our knowledge. Eventually we have to “grow up” and begin also considering the life of the mind and its relationship to the sources of our knowledge. It is in this process that we begin to see a necessary difference between the mind and matter strictly speaking.

You can often show the limitations of modern science by seeing how it tries to deal with the qualities of classical philosophy. Take colour for example. If you go to wikipedia and look up the modern, scientific account of colour and reflect on it carefully, you will find that the account is insufficient and begs certain questions or at least results in an absurdity. The modern account of colour evacuates all colour from physical reality and reduces it to a kind of information sequence with our eyes and brains serving as detector and decoder. Colour is firmly posited as being non-existent in physical reality. Of course, this begs the question as to where actual colours come from: e.g. actual redness as we see and experience it. The scientific account might confuse some thinkers by trying to reduce the colour red, for example, to a specific sequence of information or code, different from other codes or colours. Of course, however, actual red is not a mathematical equation, however convertible or expressible in math for practical purposes it might be. The scientific account modernly escapes criticism by subtly implying that there is a source of actual “redness” (like a pool of ink) inside your brain that your brain “paints” reality with when the right signals or codes are detected for so doing. Of course, this is circular reasoning and begs the question because that account holds that nowhere in physical reality is there anything actually and physically red. Hence there can’t be an actual pool of red ink somewhere in my brain at all. The consequence is that red actually becomes an entirely spiritual phenomenon and, at the same time, an enormous illusion. Reality is actually utterly devoid of any colour whatsoever (and the consequences of this are also interesting). While this might be a tempting argument for proof of an immaterial soul, it comes at a steep price : all “spiritual” aspects of physical reality are, notwithstanding, the most deceptive, illusory, useless or false. It also requires belief in innate knowledge (namely of the particular colours we see) as they don’t actually exist anywhere in physical reality. We have to be born already having “redness” somehow in us (and this obviously immaterially or spiritually, as actual redness can’t be a physical phenomenon) to paint reality with.

Redness is a physical phenomenon; it is a wavelength of visible light, which forms a band in the rainbow.

Physical objects appear red if they reflect or emit mostly that wavelength of light. Seen under another band of light, they will appear black.

We obtain the concept of redness when as children, we learn language, and come to connect the color of strawberries and apples etc. with the word “red.”


Why doesn’t consciousness (by which I mean “awareness”) itself count? I don’t see how its existence can be denied and yet I don’t see how it could be argued that it is material in nature. If I am aware of something, my intellect has given rise to something immaterial, i.e. “awareness” or consciousness.

[quote="Wikipedia, color]Because perception of color stems from the varying spectral sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantified by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully explain the psychophysical perception of color appearance.

(Emphases mine).

In light of your remarks above, explain this entry and why it is there or what it means.

This is incorrect. Firstly, if I had never seen the colour orange before, I would abstract what we call “orange-ness” from the first sight of something orange, regardless of linguistic conventions. This could happen as a child or as an adult. My concept of orange doesn’t require a word or words for it. From hearing “orange”, and seeing someone point to something actually orange, I would just learn the linguistic convention in place for communicating the idea or invoking the memory of this particular thing to others. Until then, I might just label it as “that mysterious or weird thing I saw that day in Florida” or, more specifically, “that mysterious colour I saw that day in…”

Let me be clear: I am not saying or arguing in any way that there can’t be scientific with mathematically expressible or convertible explanations of colour, especially for practical purposes or uses. I am saying that such explanations fall short insofar as they eject colour from the physical world and make its source something and somewhere else (than the physical world).

Necessarily this is also the source and explanation of colour, as only certain animals can see or have visual experiences (perception) of things, such as colour.

Key here is “information that is contained in visible light”. This information requires “interpretation”. In other words, the code requires a decoder. Important, however, is the fact that “redness”, as we see and experience it, is not a “wavelength” or other lingo for a frequency, even if that is something like a cause or trigger for its actual production or appearance in things. The wavelength, on this account, points to or stimulates the production or appearance of redness; it is not itself actually red or redness.

To put it another way, and to make it more obvious, this or that red thing isn’t actually red until some mind interprets it as such. If that is the case, then the things themselves are not coloured. And that would necessarily consume everything. Hence why I said that nothing, on the modern account, actually has colour and colour has no source or basis. The brain might be posited as the source of colour but that just begs the question, because the brain itself is a physical thing and couldn’t possibly have or possess colour. So we’re left with an immaterial mind projecting colour onto a landscape from an unknown source of actual colour based on certain light or wavelength frequencies. Now I might be tempted to argue that God directly just is that mysterious colour source but that sounds rather odd.

Again, a rock certainly isn’t conscious of its texture or hardness or coarseness nor of the relatively softer texture of the sand bed it happens to be lying in. The rock, of course, doesn’t experience any of this at all. But at no point does either the rock or the sand lose these properties or realities simply because no one is actively experiencing or sensing their relative hardness or softness (they are not dependent on mind or even sensitive creatures): if that were the case, then their entire physicality would collapse and we would be worse off than even those folks in the Matrix, as there simply would be no actual physical reality to return to. Hard or soft reflects something that the rock or sand actually has or have; and while we are certainly applying a comparative and subjective scale to them, based on ourselves, it doesn’t follow that we are giving these properties to the things themselves as if they didn’t have the basis of them in themselves. Both rocks and sand might be considered extremely soft to some mythological creature whose skin is almost diamond strong or hard and whose physical construction is like steel; however, that doesn’t change or alter the actual properties of this rock or that sand. It just changes the scale.

The modern account is this:

Photon source --> photon --> object --> photonic information --> an eye-brain mechanism --> interpretation --> colour attribution to object.

Notice where colour actually comes in, appears or originates. That’s the problem. We are entirely the source of it ourselves. We manufacture the colours; we aren’t actually abstracting them from extra-mental sources in the real world.

Necessarily, then, we must have the colours somehow in ourselves. But wherefrom? It can’t be physical; ergo…

Whoooh, you said a lot.

I will have to read this a few times to be sure what you are asking and how best to respond.


What you or I, or a colorblind human being, or a bull see as “red” cannot be communicated, except via language (which of course excludes the bull).

Otherwise we have to guess.

Thought processes are fundamentally different with and without language.

You are correct that visual learning can take place after childhood. But seeing is mostly learnt; it is not automatic. And except for special cases of blind children whose eyes are restored in adulthood, we as human beings learn seeing as infants and children.


Yes I did write a lot. Will think about ways of getting the points across more swiftly in the future.

I find this problematic as it sounds like you’re saying I could communicate a mental perception of red or redness to someone who has never actually seen red. I think that would be exceedingly difficult to do, especially only relying on written or spoken language. I don’t know if the mind can produce colours by a process of deduction or induction. Certainly it would be exceedingly difficult to verify without reference to the actual colour you are trying to get the other person to acquire knowledge of. You might, however, with great effort and care, help a completely blind person from birth to have an understanding of colour by making analogies to other qualities; I doubt, however, you could ever stimulate them to see (i.e. mentally) red without an actual sense experience of at least some colour of some kind.

I agree there is a serious difference. Language is meant, however, to reflect and communicate our thoughts. We can even guess at a person’s internal dispositions by their “body language”.

I don’t agree. I think our intuition that in sense experiences we are largely passive is more correct and defensible. I would also say that while abstraction is certainly something actively done (and so in a sense is sensing itself), it is not the same as laborious theorizing, for example.

I don’t think so. Granting the same condition you did, seeing is I believe natural to us qua animals.

Thank you for engaging me in this conversation. Hopefully we can work out some important insights.

God bless and merry Christmas.

I do think that Feser’s argument about the determination of thought is good. Concepts we use (like triangularity) do not correspond determinately to anything that we observe, yet we are capable of abstracting them. One cannot appeal to an imagistic basis, since it seems evident that there is not any image that is paradigmatically triangular, and I think it is plausible to say that we understand triangularity without the aid of a mental image (or phantasm). Issues with determination make it doubtful that our entertainment of triangularity could be associated with a neural firing pattern, since it seems in principle impossible for a series of neural firings to result in an intentional mental object.

I have seen a couple similar (but different) arguments. David Oderberg claims that conceptual knowledge is essentially dimensionless, and so cannot be realized in the physical brain (since no matter is dimensionless).

James Ross gives another argument that makes use of scientific underdetermination hypotheses. It is similar to Feser’s argument, but invokes somewhat different considerations. Ross claims that our formal thinking is defined for all conceivable inputs and outputs (ie. when I multiply NN I get N^2). But in a physical system, say a computer, that calculates 2020 = 40, the actual operation that is being done is indeterminate among “quus”-like functions (where “quus” is an operation Saul Kripke considered, where x {quus} y = x + y if x + y < 57, = 5 otherwise, or something like that). Basically, any physical system is indeterminate among infinite quus functions, where the differentiating outputs exceed any conceivable inputs, but human mental operations are determinate (we do addition, not “quaddition”).

I’m not sure that spatial triplication is an equivalent of triangularity, but maybe an instantiation of the number 3 in space. My point is that if you instantiate triangularity or the number 3 or whatever you are giving discreteness to the concept that the concept does not require. The concept, once grasped via a triangle or some material object, does not need recourse to the same triangle to be understood: the thinker understands what triangularity is and can imagine any object that is triangular. Hence the understanding is immaterial because there’s no necessary correlation to any particular material object.

I appreciate your comments :slight_smile:

I agree with everything you have said here.

I think you are thinking of “qualia” or the experience the observer has at observing color for instance that is more than just detecting wavelengths of light. This is probably related to an immaterial component of the observer. This might be an absurd example, but it may be the case that you and I have an “inverted spectrum” where we have agreed to call a certain color “red” but are actually perceiving different colors. If we swapped spectra, then each of us would have a novel experience viewing a strawberry for instance. Since the physical inputs are the same regardless (same wavelengths of light), then maybe that would be proof of an immaterial component of the human person? I have no idea if inverted spectra are real though as it seems a little bizarre. There are probably better examples but I am not too familiar with the philosophy behind qualia so I wouldn’t know what they are off the top of my head. Thank you for your input though. :slight_smile:

How are they not the same? Both give rise in the mind to what we would call a triangle. After all, not specific instance of a triangle or physical representation is needed. Three points in space, reflected in a human mind, will do it.


That’s an interesting way to look at it. I’ll have to read up on Oderberg’s claims (I’m kind of an amateur at philosophy admittedly).

I feel like I have heard of quus-like functions (I probably read it somewhere on this forum at some point, or maybe it was in a Feser article). I’ll definitely take a look at your recommended readings to get a better idea of what the arguments are. Feser’s argument wasn’t something I grasped right away. Thank you for your insights. :slight_smile:

Okay, my apologies, I see what you mean now. But imagining three points in space is giving rise to a specific triangle or physical representation. For instance, you might be imagining a scalene triangle defined minimally by a tuple of either 3 side lengths, 2 angles and one side length, or two side lengths and one angle (I may have my geometry wrong but the point remains). The concept of triangularity is not limited to these values. There is obviously a range of possible values leading to infinite combinations. We understand this without having to imagine all the possibilities.

Here’s another example: we can imagine the difference between a shape with 3 sides and one with 5 sides. We can also understand the difference between at shape with 5,678 sides and one with 12,348 sides, although we cannot imagine the difference (they would both look like circles).

Food for thought: I know that I know. This act of self awareness in itself can not be explained by physical science. I can asbstract ideas from sense percieved objects, then I can abstact ideas from knowledge of the sense perceived objects then I can abstract more knowledge from knowledge I abstracted from sense knowledge. The ability to abtract truth from matter is a spiritual process. St. Thomas Aquinas explains it as three levels of Knowledge, The sense level, the mathematical level, the metaphysical level. all of this knowledge is non-physical.except for the sense knowledge.(the animal level) Has any scientist come across an idea , its physical nature? He never will. He hasn’t made the trancendence from the physical to the spiritual. Material based science never will. The big problem is that everyone is looking for the answers in the material world. Their is a spiritual world, the world of truth and thought. If we are objective in our conclusions of the material world we will find that there are universal, self-evident truths contained therein. Our thought process is extrinically dependent on matter because of our present mode of existence, body and soul. Science hasn’t even discovered that we have a rational, spiritual soul. They keep looking for rational life in the brain. The very faculty they use to explore is not acknowledged to be a spiritual one Thought is spiritual and its activity can be deduced from the activity of the brain which stores sense impression. It is the intellect that abstract knowledge from the sense impressions. The ability to know that I know can not be explained by our present scientific findings. The act itself is like a bending back on ones-self. One scientific truth is that "two things can’t occupy the same space at the same time. If thought was material it couldn’t know that it knows at the same time. I know that I know that I am communicating through this forum, a spiritual act. How do we live a spiritual life, with our minds. How does one communicate with each other, with our thoughts,in the form of language, our intellects. We are living in a material world thats blind. Pray that our scientists are enlightened, and we too.

Except that we know that when the brain is no longer alive, no thinking or knowing takes place.

Obviously thinking and knowing require the services of that live spheroid (and by extension, the body it is housed in).


But that too is an extension of things we can see; we know how shapes change as they progress from square, to hexagon, octagon, etc, and on to that coin from Canada or Australia (maybe both?) that looks and feels almost round but is in fact 11-sided. Our mind easily jumps to the idea that these shapes would progress toward circularity (and even the Calculus I idea that a circle is a shape with infinite sides).

A truly nonphysical shape problem might be one involving 4-dimensional bodies. Mathematically, these exist, but our retinae cannot image them, nor our visual heads imagine them. They are much harder to wrap a mind around.


Yeah, Feser has defended Ross’s argument as well (Ross passed away a few years ago).

I don’t find Oderberg’s argument as imaginative or compelling (although I still think it is defensible), and in that article he explicitly does not attempt to answer critics, but Oderberg is very good at working out the details of a hylemorphic philosophy of mind (ie. what is the soul, what are the identity conditions, what are the implications of immaterial aspects of thought, etc.). Actually, all of his articles are available online, some of which pertain to philosophy of mind.

Despite the fact that some people are rather convinced by computational theories of mind, I think consideration of what computers intrinsically lack is a good way to grasp what Feser means by intentionality. Physical symbols depend on humans for their meaning. When I type “meaning” into my computer, the text only has semantic content as an extension of my understanding of it; as pixels lit up on a screen, it lacks semantic content. But similar points might be made regarding any operations of a physical system. The binary that my computer reads is an indeterminate system. It is physically active, but semantically meaningless until used for human purposes.

So physical systems, even computers, do not beget real semantic content. Computers (or handwriting, or any physically instantiated symbol) have at best “derived” intentionality. Humans have intrinsic intentionality (and we could not even speculate that they have “derived” intentionality, since human cognition seems to be the only source of intentionality we know of).

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