Evolution and humans: big brain size or use (Evolution)

by dhw, Thursday, June 08, 2017, 12:37 (2723 days ago) @ David Turell

Dhw: The women said: “I want to read,” not: “I want to rewire my brain.” The “concept” was reading, and in implementing the concept, they changed the structure of the brain. Concept first, rewiring second.
DAVID: Concept first, rewiring second is correct.

Thank you.

dhw: I am proposing that the same process resulted in the expansion of the brain, as in the spear example, with someone thinking: “I want to make a weapon,” not: “I want to enlarge my brain.” And when the brain had reached its maximum size, rewiring/complexification/ densification was the new way forward.
DAVID: We have no proof that thinking concepts enlarges the brain.

We have no proof that your God fiddled with the brain to enlarge it, or that the enlargement of the brain was the CAUSE of conceptualization, but you seem to believe it. And you may well be right, but that makes you a materialist. We do, however, have proof that “thinking concepts” causes changes to the brain, so why assume that 200,001+ years ago changes to the brain caused the thinking of concepts, and 200,000 years ago the process was reversed?

DAVID: What we have is a little used H. sapiens brain from 200,000 years ago finally being completely used in the past 10-12,000 years of real civilization and the brain densifies and shrinks, all the opposite of your struggling theory to find an internal drive, not an external change by God.

You make it sound as if your personal belief is somehow the default position! The densifying of the brain is living proof that thought precedes structural change, and so that is quite clearly an internal drive. It may have been devised by your God (the external force), just like the process of thought enlarging the brain. The fact that the brain had reached maximum size 200,000 years ago and thereafter needed to densify rather than expand offers us a seamless process of thought expanding and then densifying the brain. As above, your theory has the brain changing before it can conceptualize, and then suddenly you reverse the process and have conceptualization changing the brain. Not much logic in that. The rest of your post acknowledges the correctness of all my arguments, so in fact your only objection to my hypothesis is that it isn’t yours. As I keep reminding you, mine is the only one that conforms to your dualistic scenario in which consciousness/the self uses the brain and - crucially for your beliefs - survives its death. (But once more, I am not taking sides in the dualism versus materialism debate.)