Classmate: Hi, I'm a classmate...and I've been a huge fan of your posts and likes on facebook. [Thanks newadvent.org] I'm a Protestant Christian who's really into theology. This kinda ties into med school I guess. This is a philosophical question and I"m curious about your opinion, what would a catholic say about brain transplants. If two people were to switch brains, would the souls follow. Would they just be people in new bodies now. I'm on the fence concerning physicalism.
Me:...By physicalism, do you mean the position that holds brain equivalent to, or the only container of, the soul? It's important to be clear about terms. : ]
C: I think physicalism refers to the idea that humans are primarily physical beings and the soul is not made of another type of immaterial substance, although they can still freely make decisions because the whole is more than just a sum of it's parts. So people can still make moral choices despite not having soul substance. You don't have to answer. It's a difficult question. I was just curious. Thanks for the reply!
M: I don't think it's as difficult as you think. Watch. Our physical abilities, like our senses, our ability to move, and our imagination, need physical organs to work. For instance: sight needs the eyeball; our ability to move needs muscles, motor neurons, the motor cortex, the pons, and the medulla; and the imagination needs areas like the limbic system. But we also have abilities that come untied from physical things: our intellect for instance, can behold things totally abstract from matter (e.g. "triangle," "justice," and "God.") This non-physical power has no use or need for a physical organ. So, this part of the soul is wholly immaterial. Since the soul is not divisible, the entirety of the soul must also be immaterial, though parts of it employ physical organs. Since the brain is the organ only of a part of the soul (or, more likely, a combination of organs of various parts), transplanting it would not mean body-switching or soul-switching. It would be a pretty dramatic transplant, but the immaterial soul is not moved just because one/some of its organs are. What do you think?
C: I think that was beautiful.... It's wonderful to talk philosophy with another person....I guarantee you I couldn't have just pulled out that explanation without TAC. And what other education allows me to pull out my external hard drive and click click click to a boiled-down version of St. Thomas' five ways (which I created before Junior midterms)?
- We perceive things in motion (common experience, effect of God)
- From Aristotle's definition of motion (actuality of potency as such): nothing moves itself, everything is moved by another
- [The mobile] is [not in act]
- [The mover] is [in act]
- ∴ [The mobile] is not [the mover]
- Regarding these "anothers": there is either some first mover or we regress (which annihilates the intelligibility of the universe, which we assume)
- If there is [no first mover] there is [no second mover]
- If there is [∞ regress] there is [no first mover]
- If there is [∞ regress] there is [no second mover]
- There is a first mover. "First mover" is a name of God. Therefore, there is a God.
- We perceive an order in efficient causes now causing
- Again, the thing caused cannot be identical to the cause
- Again, there is either a first or an ∞ regress (which would be, again, absurd)
- There is a first efficient cause now causing. This we call God. Therefore, there is a God.
- We see that there are things now existing that can be and not be.
- For these things it is impossible to always exist (if not and such a thing exists at all times: it is incapable of not existing; a thing which possesses contraries is able to enact them one by one, right after another, so the contingent thing must have not been before being).
- If all are contingent, at some time nothing was (absurd)
- So there is some necessary being.
- Necessary beings are either caused or exist per se. There cannot be an ∞ regress in causes, so there must be a being whose necessary existence is per se, and this we call God.
- Gradations in things are named from the highest (of trancendentals, e.g. true, good, beautiful, one)
- Most true = most knowable = most being
- The highest in the genus is the cause, so the cause of all being/good/etc. we call God. Thus, God is.
- We see unintelligent nature (e.g. all material creatures besides men) acting for an end.
- This presupposes a good, an intention, an intelligence directing all these to their goods.
- This intelligence we call God. Thus, God is.