Brain Expansion (Evolution)

by dhw, Friday, May 15, 2020, 11:51 (1651 days ago) @ David Turell

dhw: Once more: if as you believe, your God invented a mechanism which enabled the brain to complexify itself autonomously in response to new requirements (with shrinkage simply the result of its efficiency), why should his invention not also have enabled the earlier brain to expand autonomously for the same reason? If he was happy to leave the modern brain to do its own thing (complexify), why would he not have been happy to let the ancient brain do its own thing (expand) as well?

DAVID: It is possible to ascribe any actions to God as you wish. My position remains God runs evolution, and your invented theory is not based on any factual material. I doubt if this was an issue of God's happiness. Using this brain as a model of past brains, it IS logical to assume they also complexified a little. Nothing more can be logically assumed from present evidence. But imagination can run wild.

Your theory ascribes to your God the actions you wish. My theory is based on the fact that the modern brain changes in response to new requirements, and you cannot find a single reason why the same process should not have applied to the ancient brain. Your invented theory is not based on any facts. “Happy to” was not meant to lead to a discussion on happiness. If God invented a mechanism for the modern brain to complexify independently, why do you assume that the same mechanism would not have enabled the ancient brain to expand independently? My theory is not an assumption but a theory based on the only facts we have. Your theory is an assumption based on nothing but faith in your own personal belief in God and in your personal reading of his purpose and method.

dhw: Attempted diversion through “bony problem” now dealt with three times.

DAVID: Bony problems are not a diversion. They represent a major problem for your theory. I don't remember your answer, so please repeat it. As for expansion, God did it. As for rational discussion, see above, which states it is just vivid imagination, not based on current facts.

“God did it” is not my idea of rational discussion, and your claim that a theory extrapolated from current facts is “vivid imagination” is not my idea of rational discussion either. I have dealt with the bony problem three times, the last being yesterday (bolded), and I include your irrational comment (bolded) as follows:

DAVID: And how does hard thinking get the skull to expand to allow the newly required fit, and the mother's birth canal accommodate the newborn's bigger head? The subject is the same as I raised above. Phenotypic changes all apply. Hard thinking must trigger all!!!

dhw: Hard thinking applies to the brain, because the brain is the seat of thought, whether there is a soul or not. You can never seem to get your head round the fact that the body consists of multiple cell communities which cooperate with one another, with or without your God’s 3.8-billion-year computer programme or personal dabbling. Any anatomical change will involve different cell communities cooperating.

DAVID: Of course I ignored your cell committees as totally off the mark.

First you accuse me of not answering, then you dismiss my answer (as if you alone knew “the mark”), and now you have forgotten my answer!

dhw: Three cheers for homo erectus, who clearly began with a smaller brain but went on expanding it through his thought advances (or “hard thinking”). Or are you now saying that your God must have kept “stepping in” and dabbling erectus’ continued brain expansion to enable him to think more advanced thoughts as time passed? And this in spite of the fact that as a dualist you believe that only the soul does the thinking?

DAVID: My approach never changes. God enlarged the erectus brain during its time on Earth, and the soul, using the more advanced brain size and possibly more complex networks used them for more advanced designs of artifacts.

So your God carried on dabbling to make the erectus brain bigger and bigger (and possibly more and more complex), because it couldn’t change by itself, whereas he’s now stopped dabbling because sapiens’s brain can change by itself. (And all he ever wanted was sapiens’ complexification.)

An article in today’s Times discusses the importance of highly sophisticated axes believed to have been created about 600,000 years ago by Homo heidelbergensis. “Researchers said these advances in craftsmanship suggest individuals were acquiring multiple characteristics of self-control, such as forward-planning, concentration and frustration tolerance. This happened across a broad area over a period of about 100,000 years, coinciding closely in time with evidence of increases in brain size and social collaboration.”

I like the 100,000 years reference, which lessens the drama of brains suddenly “exploding”. A materialist might claim the brain expansion (cause unknown - maybe chance mutations) led to the advances. My favourite dualist would presumably claim God stepped in with dabbles, and the soul used the bigger brain to advance skills and its own self-awareness. My proposal would be that it was the other way round – new ideas required hard thinking (concentration), and as with the modern brain, this resulted in the changes (first, expansion - probably when complexification could no longer cope within existing dimensions - then sapiens complexification).