Brain complexity: learning new tasks (Introduction)

by dhw, Saturday, November 25, 2017, 09:03 (2556 days ago) @ David Turell

dhw: I don’t believe expansion took place for no reason and without a cause!

DAVID: Remember, God did it!

I’ll keep my theist hat on, and point out that your God could have designed brain and skull in such a way that they would expand when there was a good reason for them to do so, instead of him expanding them for no reason and having them wait around for inspiration.

DAVID: New concepts require more advanced thought from previous thoughts, which is provided by larger more complex brain which permits the appearance of more advanced thought.

You are back to renouncing your dualism, since you yourself do NOT believe that thought is provided by the brain, but this actually makes no difference as I hope to show one day with my compromise between dualism and materialism! So whether thought comes from the brain or not, modern science tells us that it is the effort to implement concepts that changes the brain. You insist on having the brain change before it is exposed to the concepts that make it change. Illogical.

dhw: …if there was a sudden leap forwards 10,000 years ago, it could only have been because certain…individual brain communities came up with new ideas..

DAVID: All of us had bigger frontal lobes and more cortex. We could easily accommodate the new concepts.

Bigger frontal lobes and more cortex were the “end” product of a series of expansions caused by the accumulation of concepts requiring more cells for their implementation. By the time of the leap, expansion had long since stopped, and new ideas resulted solely in complexification (apart from the initial min-expansion).

DAVID: …based on what we know about brains, each stage of hominin brain started with a set size and degree of complexity and could expand and contract with developing thought within the same skull size until the next large jump in sized appeared through God's intervention. (dhw's bold)

Based on what we know about brains, they change IN RESPONSE to new tasks, so please replace the words in bold by: “until the next large jump in size appeared when the process of expansion and contraction proved inadequate to implement new or more advanced concepts”.

DAVID: Your theory never explains a 200cc jump in size. Only God explains it.

My theory explains (for the umpteenth time) that a jump was necessary when the existing size could no longer cope with the demands made on it by new tasks and concepts. It also explains how and why other organisms, from immune cells to pre-whales, also change their structures without any need for your God to preprogramme every change or to dabble personally. But he may have designed the mechanism enabling organisms to make the changes.