Let’s see—we were talking about the act of “understanding” something. You then said such acts were functions of the brain. This strikes me as a statement of faith, not an empirically demonstrable fact.
Yes, that has not been
proven conclusively. However, there is
a lot of evidence for it. First and foremost if some part of the brain gets a minor damage, for a while the person may experience some degradation of his mental faculties. However, other parts of the brain may “take over” and the person can regain his full faculties.
A simple operation of lobotomy can deprive the person of his personality. Etc… every piece of evidence point to the conclusion that the “non-physical” mind is just the activity of the brain. By putting some electrodes into the brain and stimulating it with mild electric current we can invoke pleasure and pain, strange thoughts, maybe even cure some diseases.
The old Greeks thought that the brain is just a cooling device for the blood. We are much further ahead on the road, though admittedly we are still very far away from the end.
Furthermore, the “meaning” of the thoughts or the “understanding process” will probably never be
fully reduced to the dancing of the electrons in our brain tissue. That should not come as a surprise and it does not point to some non-physical “soul”. The “wetness” of water is an emergent attribute. It cannot be reduced to the properties of the oxygen and hydrogen atoms which form the water molecule.
The laws of chemistry are not derivatives of laws of physics. Yet, there is no assumption that “wetness” of the water requires a non-materialist explanation. The laws of biology are also not derivatives of the laws of chemistry. However, since the laws of biology are still less understood than the laws of chemistry, some people tend to bring up non-materialistic arguments for the “conceptualization” type of working of the brain. There is no need for that.
Certainly the mind uses the brain. However, just because physical activity in the brain subserves thought doesn’t mean it is identical to thought; in fact, I’m not sure how some physical processes in a big chunk of matter could be said to “understand” anything.
The mind is an emergent attribute of the brain, or the working (activity) of the brain. How it happens, is a very fascinating problem.
The act of understanding indicates the presence of a rational soul, which “interfaces” (to use your term) with the physical, but which cannot be reduced to the physical. (I do realize there are many,many attempts at such a reduction currently underway.)
I suggest the use of the phrase “rational mind”. As I said above, the full reduction may not be possible. Just like the laws of chemistry are on a “higher level” of complexity than the laws of physics, it does not follow that the laws of chemistry require a non-materialistic explanation.
The reduction you speak of is the topic of artificial intelligence. When the first computer program will pass the Turing test, it will prove conclusively that the “understanding process” is a fully materialistic one - at least in the case of a computer.
So here’s an argument in the attempt to lift the discussion past the “minimum assumption.” The conclusion is that non-physical elements of the universe exist.
I never denied that. Concepts are not physical, onlological objects. So, I don’t think we are out of the scope of the original “limitations”.
But not just concepts. The patterns or arrangements of ontological objects are also non-physical. If you consider six carbon atoms, they can either be arranged in the shape of a hexagon (graphite) or on the vertices of an octahedron (diamond). These arrangements exist whether there is a conscious mind to perceive them or not. The geometric patterns are not physical objects, they are the relationships of physical objects.