Brain expansion: different theories about rapid expansion (Evolution)

by dhw, Monday, August 31, 2020, 12:37 (1543 days ago) @ dhw

dhw: …if the designer did not tell us how to use our brains but anticipated how the enlargement would be used and what all hominin/homo enlargements might achieve, please tell us what he did anticipate if he didn’t anticipate what we achieved.

DAVID: God gave us free will, remember? He could not anticipate every invention of activity by our every active souls using our brains.

You have told me why your God did not anticipate what we achieved, but I asked you what he DID anticipate.

dhw: You are the one who ignores even your own knowledge about the brain: “Our brain has the adaptability to react to any and all physical and mental and emotional demands we place on it.” These reactions take place without your God’s intervention and would also have taken place in each pre-sapiens brain. Same mechanism, same autonomy. […] Do you really think the same autonomous mechanism is incapable of providing itself with more new cells, even though it still does so on a minor scale?

DAVID: The evidence from our brain is clear. Only a few new cells are made by our extremely accomplished organ. No evidence for your theory.

Nobody knows how the brain expanded. The fact that our brain changes as a REACTION to any and all physical and mental and emotional demands made on it, and even produces a few new cells in doing so (although it has stopped expanding overall) seems to me to provide sufficient evidence for my theory to be regarded as feasible. There is no evidence that one fine night God stepped in to perform an operation on a group of Moroccan brains, skulls and pelvises.

dhw: We have covered the stasis argument a hundred times. Once the pre-sapiens brain had expanded, there were no major new ideas until about 280,000 years had passed. There were similar periods of stasis after earlier expansions. It appears that our brains began to change again about 35,000 years ago, when there was a sudden burst of innovative activity. That fits in with my theory. The brain REACTS to new requirements, not in anticipation of them.

DAVID: It reacts only if it large enough and complex enough to allow new thought by the soul.

But it has been demonstrated, and even stated by yourself as bolded above, that the brain REACTS to new requirements. There is no evidence that it expands or complexifies in direct anticipation of new thoughts. This should not be confused with the fact that once the brain has expanded, the dualist’s soul may continue to come up with new thoughts which will in turn require new complexifications and, in pre-sapiens times, new expansions.

DAVID:The bold forgets my discussions of molecular errors. In advancing evolution God can not trust a DNA design mechanism totally on its own!

Your discussion of molecular errors finished up with you telling us to ignore them and focus on the 99.99999% success rate. Why would your God have to perform an operation in order to expand the brain if his beautifully designed mechanism for brain adaptability to react to any and all demands was working as it should? Are you saying every expansion was a correction of what had gone wrong?

DAVID: Your interpretation of how a brain reacts does not include any evidence of enlargement. I have bolded my comment about errors. Advances in evolution are so complex only a thinking biological engineer can create them. The brain has never been shown to enlarge itself to the degree seen in fossils.

Once more: Nobody knows how the brain expanded, and our brain has stopped expanding overall, which is why we have to theorize. See above for the rest of the argument.