Brain expansion (Evolution)

by dhw, Sunday, June 21, 2020, 10:13 (1405 days ago) @ David Turell

dhw: The push for pre-sapiens enlargement came from a requirement which could not be met by the existing capacity for complexification. Once the brain had enlarged, there was comparative stasis in the new “culture” in all instances, including sapiens, and so we can only assume that there were no new requirements, or those that there were could be deal with by complexification. You seem to think that once the brain had expanded, the dualist’s soul should have come up with millions of new ideas. Wrong way round, as usual: it is the soul’s new ideas that would earlier have required complexification and then expansion, and which in the modern brain cause complexification, which in turn is so efficient that it has caused shrinkage.The dualist’s brain does not produce ideas – it responds to the ideas conceived by the soul.

DAVID: The bold is correct in my view. Our obvious difference is you think the soul can come up with concepts without using a brain during life, and therefore is able to push the brain to a new size so the brain can accommodate the drive for new thought.

This is a travesty of what I have proposed! The dualist's soul comes up with concepts based on the information provided by the brain, and I don’t even know what you mean by “accommodate the drive for new thought”! The brain implements the concepts that the soul comes up with.

DAVID: Obviously I think all of your paragraph is backwards, just as you claim about my thoughts. The red sentence is previously covered. We both agree to a stasis period but interpret it differently: you think a tidal wave of unrealized soul concepts forces expansion. My question is, as above, if that is true why does the appearance of those new concepts take so long?

Another travesty. Each expansion would have been caused by the fact that the existing brain did not have the complexification capacity to implement a new concept. After each expansion (up to and including sapiens) there was a period of stasis because the dualist's soul did not come up with any new concepts that could not be dealt with by the existing mechanism of complexification. The red sentence obviously has not been covered, since you are again assuming that pre-sapiens and sapiens souls should have come up with millions of new ideas immediately after expansion! Why?

dhw: Why do you think that a God who invents a mechanism enabling cells to expand their number autonomously = a God without purpose, whereas a God who invents a mechanism enabling cells to complexify autonomously runs evolution with purpose?

DAVID: Binary fission is the standard automatic way cells reproduce and multiply, without change in the cells or their functions. True evolution requires change and controls.

How on earth does that prove that God is incapable of inventing a mechanism enabling cells to expand their number, or that to have done so would have been without purpose?

dhw: So you do think the switch to large pelvises happened overnight. […]

DAVID: All solved if you can see God does it simultaneously. Otherwise no advance, just death.

dhw: The only observable parallel we have is modern adaptations, from bacteria combating new medications to fish learning to live in polluted waters. Many die before the adaptation is complete. But of course you are welcome to believe that your God did an overnight operation on all those ancient homos’ brains, skulls and pelvises. What a shock they must have had when they woke up next morning!

DAVID: Those examples you give are gradual adaptations over time, involving paired problems, as bacteria and new drug. In causing a gap in species we have three contributors, Mom's new pelvis shape, Dad's sperm input and Baby's bigger head, and in the gap from apes, the additional requirements for upright posture. Why don't you consider the problem of the whole continuum of evolution instead of bits and pieces? It is entirely obvious adaptation doesn't work. You can't have several adaptations going on at the same time and rate without careful coordination.

It is you who divided the process up into bits and pieces: brain, skull, pelvis. And it is obvious that adaptation did work! The brain expanded, the skull expanded to accommodate the brain, and the pelvis expanded to accommodate the larger skull! In all adaptations, the relevant parts of the body require “careful coordination” or intelligent cooperation. You have your God dabbling with a group of homos, simultaneously expanding their brains, skulls and pelvises overnight. I suggest a more gradual process, no doubt with casualties (and a lot of pain) on the way, as the pelvis responds to the need for expansion until eventually and naturally only the larger pelvis survives. We cannot reasonably expect to find fossils recording every stage of transition. Why do you find this hypothesis less convincing than your own?