Introducing the brain: half a brain is just fine (Introduction)

by dhw, Wednesday, March 18, 2020, 08:52 (1501 days ago) @ David Turell

dhw: […] if the present brain is built on the past brain, there is no reason to assume that its process of changing itself in response to new actions was reversed in the past by changing itself in anticipation of new actions.

DAVID: That can be your assumption, but it is not at all the same as our brain confining some new activity to a small enlarged area.

dhw: It is a theory, not an assumption, but you are dismissing it because you assume that the modern brain functions differently from the past brain. The similarity lies in the fact that in both cases there is expansion. We know that in the present, expansion is a response to requirements.

DAVID: My only point is our brain is a major advance over other brains, and may operate differently because it is so advanced. We do not know how Habilis and Erectus expanded, but we do know about a 150 cc shrink age of our brain as how to fully use it was learned from 315,000 years ago.

Nobody would deny that our brain is an advance, and yes it may operate differently. But there is no reason to assume that it does. Your final comment is irrelevant since it is the cause of pre-sapiens expansion that we are discussing!

Dhw (ignoring materialism for the sake of argument): I suggest that once the dualist’s brain has expanded, the dualist’s soul will continue to use it until the next point at which existing capacity is insufficient. Sapiens’ brain reaches capacity, and so the soul continues to use it for new concepts, but instead of overall expansion, there is now advanced complexification, minor expansion, and shrinkage caused by the efficiency of complexification.

DAVID: Good summary, especially the point about the shrinkage, despite the constant development of new concepts. There is no indication it requires any new enlargement. it appears to be totally adequate for the demands.

Of course sapiens’ brain doesn’t require new enlargement! Complexification has taken over from enlargement (except in small sections). We are discussing the CAUSE of enlargement (though I suggested earlier that in sapiens complexification took over in order to avoid the anatomical complications expansion might have caused).

DAVID: The problem is the innate ability for an existing underlying brain to accommodate the development of new concepts.

dhw: Precisely. And in the past, the existing underlying brain could not accommodate the development (i.e. the actual design and implementation of the new concept, not the conception itself) and therefore had to expand. You’ve got it!

DAVID: Precisely the opposite approach to mine.

Then why did you pinpoint the problem of the existing brain accommodating the development of new concepts. Your argument till now has always been that you don’t believe the existing brain (though as a dualist you should have said soul) could conceive the new concepts. It is my argument that it can’t develop them.

DAVID: Your theory is: The effort to find a new concept doesn't need a new complex brain expansion, but building the new artifact does it!

Not just building it, but working out the detailed design of something that has never been thought of before! What you called “abstract thinking”. In our modern examples (illiterates, taxi drivers, musicians, possibly Einstein) it is the mental effort that causes minor expansion. With our spear example it would be the mental effort plus instructions to the brain to get the body to give physical form to the concept (implementation).

DAVID: Backward, inside out illogical thought. Abstract envisioning of a new artifact and how to build it is the key step. Actually constructing it is the easy part. I know. I've designed and built things (sheds and barns). I've designed two homes; also two medical clinics, two dialysis units, two business offices and two x-ray departments as part of my work at my clinic, all accepted by the other doctors and the architects as having excellent traffic flow. The later construction was the easy part as blue-collar folks followed the instructions.

I have nothing but admiration for your extraordinary range of talents, but in designing and building, you were using existing information that would not have been available to the very first inventor of dialysis units and x-rays and even such things as doors and windows.

dhw: The FIRST artefacts would have been the product(s) resulting from whatever concept(s) CAUSED the pre-sapiens brain to expand to sapiens size. There is no way anyone can possibly prove or disprove this, because an artefact can only exist once the brain has finished expanding through the effort to design and make it.

DAVID: The bold is still your reversal theory of the series of events archaeologists appear to believe.

I’ve no idea what they believe. How many of them have specified that God expanded the pre-sapiens brain, and only then was it possible for the soul to conceive of a spear?