It has for some time seemed to me that the definition for soul is very simple, and that the existence of the soul is quite obvious. The soul, at its most basic when all else is stripped away, is simply the “most basic component of ‘self’.” Not the personality. Not the thoughts. Not the actions. Simply the most basic component of what we call “self.” This is indeed very difficult to explain, but to exist is to know it, even if by “over thinking” it you forget that you know it (as many modern materialists do).
Imagine a person who is made entirely of all the same physical material that our bodies are. Has the same brainwaves as we do. Can talk as we do, have measurable (from the outside) thought patterns as we do, eats as we do, cries as we do, has the same chemical reactions that cause emotions, etc. Now realize one thing: If you, yourself, judged this being based only on his own merits, not bringing your own existence into account, there is absolutely nothing that proves that he is not just a complex computer. As in, “not a self,” but only a blind mechanical sum of parts. Or, what some philosophers call a P Zombie:
en.wikipedia.org/wiki/P_zombie And indeed, there is absolutely nothing physically measurable to prove, beyond the shadow of a doubt, that a human being is NOT that…except that we know better
only by virtue (besides revelation) of
being human and thus knowing that we are not “blank” inside. Yet because
matter cannot account for this, I believe that the
soul is that which separates a genuine living thing from a “P Zombie.” The soul is that which enables us to have “Qualia”.
en.wikipedia.org/wiki/Qualia
You see, the problem with positing a soulless being is that there is absolutely no logical reason to believe that a soulless being, no matter how many complex brain patterns, emotion-emitting chemicals, or whatever else it had, would be any more “alive” on the inside than a highly advanced PC which was just following programming. The PC does not look out and “feel”. Any “emotions” of an AI are really just blind programming signals which are not being experienced by any actual “entity” on the inside. And indeed, if the material was all that a biological organism was, I find no convincing reason to think that biological organisms would be any different.
Think of this: All physical things are made of parts, and ultimately all different physical “things” are made of the same “stuff.” The same protons, neutrons and electrons that make up a speck of dust are simply combined in a different way and in a greater number to make up the physical human body. Ultimately, this means that physical things are a kind of collage: If looked at on the subatomic level, one could actually
see that it was all the same (it’s all protons, neutrons, electrons, and energy) just in different arrangements. Yet a collage only appears to be anything meaningful because there is an observer to make sense of the collective “picture.” If the human entity were only a collage, however, what “observer” is making it appear to be more than a collection of protons, neutrons and electrons such as can be found in even the most basic matter? If there is no soul, there would be no such observer, and there should–by all logic–be no more real “life” inside of a human being than inside of a rock or a fancy computer; the human, though he would move and breathe and such, should be just as “blank” on “the inside” as a piece of paper…
Yet we know that the human being is NOT such. There is “life” in him that cannot be accounted for by matter alone. That life must be something not made of parts (or again, it would merely be like a collage). It must be something that therefore would not decompose. That life is what we call the “soul.”
Now, the Catholic concept of “soul” is more than
just that (for example, the human soul has a “will”, and thus is what influences the brain so that it is not just blindly following chemical impulses and reactions like an A.I. would), and the
full “self” is certainly not complete with a “soul” alone, which is why ultimately we are supposed to have bodies again after the last day; in the meantime, presumably, God empowers the souls in Heaven with a means of knowledge, experience, and action that does not require a body. But still, the basic premise remains that the soul is, at its most basic level, the “life” that simply cannot possibly be accounted for by matter as far as reason has ever permitted me to fathom. It simply cannot conceivably be made of lesser parts and, for that reason, is the one thing that would retain an existence of its own even IF everything else–body, mind, thoughts, experiences, emotions–disintegrated away.