Introducing the brain: half a brain is just fine (Introduction)

by David Turell , Saturday, February 22, 2020, 18:16 (1524 days ago) @ dhw

dhw: Whatever may be the source of ideas, it remains a fact that nobody has ever seen a brain complexify or expand in anticipation of new ideas. All changes we know of take place as a response to new ideas.

[dhw] DAVID: (This is you speaking, not me!): The bold is a statement as if fact.

dhw: Then please give me a known example of brains complexifying or expanding in anticipation of new ideas.

A conclusion: more advanced artifacts appear only after a new-sized brain is present.

DAVID: All we can know from the past is brains enlarged and then new processes and new concepts appeared. Erectus never had concepts habilis exhibited or then H. sapiens developed. Larger brains required for the conceptual advances.

dhw: You have no way of knowing whether the enlargement preceded the concept (larger brain thought of and implemented spear) or was caused by it (small brain thought of spear, needed larger brain to make it). However, once the larger brain was there, then of course there would have been more new concepts and implementations, until once again the capacity was exceeded by new concepts requiring greater capacity.

Totally backward thinking. New artifacts only after big brain is on the scene.

DAVID: God gave us all the brain required with its plasticity/local complexification abilities.

dhw: I answered your point about shrinkage. Why won’t you tell us your own theory about it?

Obviously plasticity with complexification created the shrinkage, an attribute of our brain given by God.

DAVID: An early erectus brain lacks the capacity, as you admit, so cannot know what a habilis can know or imagine. Your view presents us with a totally illogical theory. What pushes brain committees of neurons if they do not know what they do not know and cannot know? You theory still requires the push of foresight.

dhw: Habilis preceded erectus.

Thank you for correcting. My aging brain stumbles at times

dhw: I don’t want to get into specifics, but of course later species would already know the concepts of their ancestors and would then add their own concepts, so the earlier species would not have known what the later species knew. Hardly a revelation.

Finally good logic. The new big brain gave the later species the ability to add new concepts. So where is the pressure for enlargement if the older group could not conceive of them?

DAVID: There are currently indigenous tribes now extant that live in roughly the same fashion as 315,000 years ago, with the same sized brain as the rest of us. […]

DAVID: Please understand the indigenous simply haven't bothered to use their big brain.

dhw: That’s what I’ve just told you.

My point is why did they bother to get the big brain if it wasn't required. Note the hobbits below.

DAVID: They just like it as it is. Note the illogical bold. The indigenous have not required the big brain so why did they get a big one? The Homo Hobbits had a small brain and lived as the indigenous until 30,000 years ago before disappearing. Why didn't they get the required big brain?

dhw: My point is that they DID get the required brain – though I don’t want to speculate on who turned into who. You have a succession of enlargements and a succession of species, each one caused by new requirements. The smaller brain disappears...stasis…THEN new requirements…enlarged brain…disappearance of smaller brain...on and on until the final enlargement with sapiens. The indigenous are sapiens. They’ve got the big brain but they don’t use it as much as you do. What’s the problem?

If a prior species does not have the brain complexity which allows the self/consciousness to know of new concepts/inventions, how can there bean pressure for enlargement? You can't wish for that of which you have no conception.