How can the immaterial (Soul) affect the material (brain)

How can the soul and brain work together? If the soul is neither energy nor matter, how can it work with matter?

It is very hard to stop thinking about soul and body as two distinct substances (meaning: entities) that somehow interact with each other. And if that is so, then your objection makes perfect sense. How can a non-physical substance interact with a physical one?

St. Thomas is our great help here. He has shown us the soul as the form of the body. What is the form? If I had to choose one current word, I would say logical structure.

Every being has a logical structure. Say, two houses made of the same materials. Their matter is the same (bricks, glass, etc) but they have two different projects. The project is the form, and it determines what the house is: its functions, its spatial distribution, its colors, etc.

The soul is like the project of the house, with one big difference: the project is static, houses don’t have a “behavior”. The soul of living creatures, by contrast, includes also the behavior of these creatures. In everything soul and body operate together; and it would be impossible to have one without the other (the human soul being an exception to this because it has one function that, even though uses the body, doesn’t depend necessarily on it: rational thought). What makes a lump of chemicals into a living, breathing individual? The soul, the form, the logical structure, the ordering principle. It is not something that exists on its own and somehow interacts with the body; it is the way the body is ordered and acts.

A Human is made up of {Spirit, Soul, Body}

What about the Human ‘‘Spirit’’=Mind=Higher Self?

Well, that is a very interesting point of debate.

St. Thomas, and I follow him in this, denies the distinction between spirit and soul. Our soul is spiritual because it is rational. Therefore, it can subsist without the body (provided it once existed with the body). There is no “higher part” other than the reason itself.

How about God? Is God not immaterial? How can he affect the universe if he’s immaterial?

Okay, so on the basis of this “behavioral” criterion, not all living human bodies have rational souls, since not all living human bodies display rational capacities?

The problem for Thomas still seems to be: how can a separable intellectual form (which is at least potentially a substance in itself, since it is separable) simply be the form of a material substance? In other words, how can it be reducible to the form of a material substance, if it is separable? If it just is the form of the body, how does it exist apart from the body?

Well soul= Emotions=Love, hate, fear, happiness, Jealousy, Pride, Anger, lust, sadness depression Etc

And Spirit= Heart+Mind=Intellect.

The bible is very clear about the distinction between the ‘‘Soul’’ and ‘‘Spirit’’ of Man.:shrug:

How can the soul be spiritual when it is controlled by Emotions.

You have use your spirit with the help of the holy spirit to control your Soul!

The soul, like God, must be a counterforce to the 2nd Law of Thermodynamics. As such, it has, like God, the potential to actually create matter from energy, as God did in order to create the universe.

Materiality or not has little to do with creation. The universe is 72% dark energy, 23% dark matter, and 4.6% regular matter. You are therefore trying to understand a large puzzle by looking at 5% of it and trying to figure out how that came to be.

Damned good question, nonetheless. I hope that you retain your curiosity. :slight_smile:

Not at all. The human bodies that do not have rational activities have a physical, material impediment. Someone with severe retardation has a very definite physical cause for their problem; one that is, in principle, curable, if only we have the technology.

Well, if that is so, then it is very easy to prove the soul doesn’t exist. Just notice how nothing that happens in the human body (including the human brain) contradicts the laws of thermodynamics.

Oh, if that is your distinction, then it’s fine. Some people say that the soul is the reason, and the spirit is something higher.

However, keep in mind they are not two different things, but only one. We have one spiritual soul. And it is all right to call the more “animal” functions soul (as we have it in common with all animals) and the properly rational functions spirit.

as the the “spirit - soul” distinction.


367 Sometimes the soul is distinguished from the spirit: St. Paul for instance prays that God may sanctify his people “wholly”, with “spirit and soul and body” kept sound and blameless at the Lord’s coming. The Church teaches that this distinction does not introduce a duality into the soul. “Spirit” signifies that from creation man is ordered to a supernatural end and that his soul can gratuitously be raised beyond all it deserves to communion with God.


…very carefully…:coffeeread:

The human soul can exist without the body because the soul is connected with your human spirit.

I was talking with One christian about memory brain cells. I said how can the soul+spirit have memory when it has left the physical brain. He said the memory still functions fine when the Soul+Spirit has left the body.

But i have come up with a new Question. If a physical brain is damaged or diseased and it is severely affecting your memory. Why cant the soul+spirit override and still maintain perfect memory?

Its power to communicate what it knows is necessarily restricted - like a guitarist with a damaged guitar…

Excellent point. However, I suspect that you are arguing from theory rather than experiment. Thermodynamic measurements on closed physical systems are extremely difficult to make, because of the difficulty in truly closing a physical system. The best we can do are approximations.

A neurosurgeon can duplicate a human act of will during open skull surgery by using an electrode to induce a very small current at a point within the brain. The amount of additional energy is small compared to that which the brain is using. I doubt that an observer could detect the difference.

By analogy, suppose that you treat an airborne 747 as a closed system. The plane is controlled by small, low force movements of the pilot. Do you imagine that it would be possible to thermodynamically isolate the little bit of heat energy generated by his actions from all other sources in the aircraft?

Finally, the soul will not act upon the brain by tweaking neurons. That’s a digital problem, and the soul is an analog thing which must act via low energy waveforms.

Experiments have been done by using external coils to induce magnetic fields within the brain (e.g: the silly “God helmet”) The induced fields add little energy to the brain and probably are no more capable of thermodynamic detection than those induced by cell phone use, or simply sitting within 100 feet of a power transmission line. They can be detected electrically, of course, if one knows which frequencies are involved.

There are few experiments which even vaguely relate to this issue. However, I believe that the amount of energy used by the human brain to sustain normal sleep is comparatively much greater than that needed in animal brains. I propose that the additional energy is necessary to suppress soul-level consciousness.

Thank you for bringing up a well-considered argument.

He can, if He is a counterforce to the 2nd Law of Thermodynamics.

It is important to make a firm distinction between material and physical. Everything in the universe is, by definition, physical. That’s why the mother of all science is called “physics.”

Most of the study of physics involves immaterial aspects of the universe, electromagnetic stuff and the like. Light is immaterial, but you cannot have a universe without it.

Therefore I have personally concluded that while God is immaterial, He is certainly physical. The same reasoning applies to the human soul— physical but immaterial.

Your Christian correspondent has not studied the issue and is speaking from metaphysical lore. For a short period of time after death, a soul may retain an analog of the brain’s waveform memory, kind of an epiphenomenon. This memory will fade w/o a brain to supply its underlying neuronal structure.

When that happens, only conceptual memory will remain. That is, your deepest levels of understanding. Those who have acquired no such levels of understanding will simply go unconscious and eventually die.

Your question applies, of course, to death as well as brain damage. One might regard death as the ultimate brain damage. Knowledge gained from brain damage studies can be applied to post-death considerations.

Should a soul get reincarnated, as some belief systems hold, what it retains depends upon the age at time of death, and the time period between lives.

Detail memory has a latency time, and if one returns before it has faded (typically happens to dead children) it can be sustained for several years. Conceptual memory is the stuff that you find, as you go though life, that you already know without being taught.

Live, brain damaged individuals are locked into their brain’s memory. The longer they persist connected to a damaged brain (e.g. Alzheimers victims) the more hard-earned memory they will lose, eventually wasting a life. From the evidence I’ve seen, people with an extensive conceptual memory do not get Alzheimers. Nor do those who engage in partnership dancing.

The soul is extremely weak compared to the brain, and cannot “override.” Memory stored in the brain which has no relationship to the soul’s conceptual understanding, if any, cannot be retrieved or recreated. An override would be the equivalent of a 747 pilot going out on the wing and working ailerons by hand when the aircraft hydraulics fail. Not happening. And in most advanced Alzheimer cases, the pilot has already bailed.

Hey Greylorn,

I made a thread earlier called “Mental Illness and the Soul”. I’m not sure if you had a look but this post answered a lot of my questions on the issue, on a different thread too! :slight_smile:

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