Big brain evolution: brain size and intelligence (Evolution)

by dhw, Thursday, April 19, 2018, 12:17 (2408 days ago) @ David Turell

DAVID: Of course the materialism of the issue is shown by what happens in the brain.
dhw: It is not clear to me whether your final sentence is or is not an acknowledgement of the materialistic/dualistic dichotomy I keep pointing out in the scientific research and in your own insistence that, despite your professed dualism, the s/s/c can only THINK by using the brain except when it hasn’t got a brain to think with. Do you or do you not acknowledge this dichotomy in both contexts?
DAVID: I can only repeat what I believe: in life the immaterial s/s/c cannot think without being attached to the material brain. When the brain is not functional the s/s/c changes its quantum mechanism slightly and exists in an afterlife. Your version of duality is certainly not mine.

Of course the mechanism would have to change if there is no material brain and no material world for the immaterial s/s/c to interact with! That is not the issue. The issue is your insistence that in life the s/s/c cannot THINK without being attached to the brain. Contrast this with the following exchange at the end of your post:

Dhw: Yes, the thinking mechanism must work together with the implementing mechanism in life, in order to give material expression/form to its thoughts. So do you believe that in life you have an immaterial thinking soul (software) which interacts with the material brain (hardware) by using it to gather information and to implement its thoughts? A simple yes or no may end this set of ping pong and we can start the next.

DAVID: Of course, yes. As I have always explained your view of dualism is not mine.

How can you say yes and then claim that our view of dualism is not the same? Our view is identical! You agree that in life the soul (software) does the thinking and interacts with the brain (hardware), which does the implementing. It is therefore a blatant contradiction for a dualist to argue that THOUGHT depends on the size of the brain. It must be the ability to implement that depends on the size of the brain.

DAVID: My pointing out the shrinkage is that the demonstrated shrinkage is opposite to your view that the desire for implementation of concepts forces a new sized brain to carry that out. What we see is a brain that is able to complexify and shrink 150cc in size while developing complex concepts and carrying them out. I agree with you that it is new complexity
dhw: Shrinkage is in sapiens, and I keep offering you an explanation for it. My hypothesis of concepts forcing expansion refers to pre-sapiens. Once more, here is my hypothesis step by step:
Pre-sapiens: small brain, new concepts force expansion of brain and skull to implement them.
Sapiens: brain and skull have reached maximum size for comfort. New concepts force complexification and limited expansion of certain areas within given skull size. Efficiency of complexification causes overall shrinkage.
DAVID: The only evidence we have about brain activity (shrinkage) is in sapiens but it might just as well apply to all pre-sapiens, since evolution builds on mechanisms of its past.

We are trying to find out why the pre-sapiens brain and skull expanded. We know that the brain changes as it implements new thoughts, and modern activity includes expansion and complexification as well as shrinkage. If evolution builds on mechanisms of its past, it is only logical that pre-sapiens brain-changes also took place through the implementation of new thoughts. Whether it shrunk and complexified as well as expanded is irrelevant, since we are only interested in the cause of expansion.

dhw: Please explain in equally direct terms what you object to, and please explain what you think is the cause of shrinkage.
DAVID: Agreed Lucy couldn't think like we do. But remember, 20,000 years ago no one could think like we do, but 150cc smaller brain and the s/s/c have vastly more complex thinking.
dhw: Yes, we know the modern s/s/c thinks vastly more complex thoughts. I have explained that thought evolves, as generations build on the thoughts of previous generations. Are you now saying that shrinkage has CAUSED the new thoughts?
DAVID: No, brain complexification caused the shrinkage as demonstrated.

Thank you. So you now agree with my hypothesis concerning shrinkage, and you have agreed that the same processes we know today (thought causing brain change) would have applied to pre-sapiens and can therefore explain pre-sapiens’ brain expansion. What are we arguing about?