Big brain evolution: learning new tasks (Evolution)

by dhw, Sunday, April 29, 2018, 12:31 (2398 days ago) @ David Turell

DAVID: A bigger brain requires a bigger skull and a different Mother's pelvic shape, all coordinated at once. Requires design across two sexes. Not by chance.

dhw: Where have I said it was by chance? The issue between us is whether the pre-sapiens brain expanded before he had his new thoughts, or as a result of his having new thoughts. I have used your own computer analogy to explain the illogicality of your argument, and so you scuttle off to the chance issue. I presume you now accept my argument but are reluctant to say so.

DAVID: I don't accept your argument. You like to isolate issues without looking at the whole picture that surrounds them. How to go from smaller prefrontal lobe to larger is your nebulous 'push' concept, which just happens because it has to. I go back to design because it is obviously necessary.

It is not nebulous. We know that the implementation of concepts causes brain changes in sapiens: complexification and limited expansion (with shrinkage probably as a result of efficient complexification). There is no reason to suppose that the same processes did not take place in pre-sapiens, with the brain and skull expanding when their capacity had been exceeded (as in the computer analogy below).

DAVID’s comment (under “Neanderthal brain difference”): This study certainly shows a species can only think with the brain it is given, and more complexity gives more complex concepts.
dhw: Yes, it takes the materialist view for granted: that the material brain is the source of concepts. You have once again forgotten that you are a dualist.
DAVID: Total misinterpretation. The s/s/c uses the brain it is given to have the level of thought complexity allowed. I view the issue as the s/s/c is confined to a level of thought complexity in the brain it is given. You like an s/s/c free as a bird, always thinking what it wants despite the brain. You accept my software/hardware analogy and then totally forget it.

Your software/hardware analogy has the s/s/c doing the thinking and the hardware doing the implementing. When the software presents new concepts, you need to update your hardware. You do not stop producing new software because your computer can’t cope with new ideas. You wrote: “More complexity [of the brain] gives more complex concepts.” More complex hardware does not “give” more complex software.

DAVID: A new species is supposed to have new abilities, and that certainly can be a new level of thought as well as new levels of implementation all at once.

Thank you.

DAVID: This thought shows your step wise approach to the jump in pfc size is not appropriate to what we see in evolution.

You have just agreed that speciation can be the result of new levels of thought and implementation (= a new step) and now you say that is not what we see in evolution!

DAVID: The central theme of evolution is that tiny improvements in fitness can steadily accumulate resulting in a new species.

And now you scuttle back to the small-step gradualism that we have both rejected.

DAVID: The unstated assumption (usually) is that the original species was in need of improvement. That is your approach from Darwin. I have not accepted it as causing evolution. God drives the complex advances.

I have never stated that the original species was “in need of” improvement. I have stated that evolution proceeds through the drive for survival and/or improvement. A land animal may enter the water because that environment may offer improved chances of survival. But its mates may stay on the land and still survive. If it likes the new environment, it may improve its ability to live there by transforming its legs into fins. I don’t know why you find this logical progression so difficult to accept.