Big brain evolution: changes in sapiens skull shape (Evolution)

by dhw, Friday, February 16, 2018, 13:35 (2470 days ago) @ David Turell

I am combining this thread with “Brain complexity” as the arguments overlap, and I have tried to edit out most of the repetitions.

dhw: …you are forgetting yet again the very essence of your dualism and your analogy, to which you have agreed over and over again: that the software (s/s/c) thinks up the concepts, and the hardware (brain) implements them. The hardware does not “allow” the software to think!
DAVID: And you are not following my concept. only an advanced hardware brain allows advanced thought. Erectus s/s/c is not sapiens s/s/c.

No, I don’t follow your concept, and I keep pointing out that you use NDEs as evidence for your dualistic belief that the s/s/c is responsible for thought. That is why dualists believe that in earthly life there are TWO separate entities that work together: 1) mind, 2) body. Forget about “advanced”. Thought is thought, whether it’s advanced or not. The brain does not “allow” thought because, as you keep agreeing, the s/s/c does the thinking and the brain gives material expression to the s/s/c’s thoughts, just as the hardware gives material expression to the software. The s/s/c evolves, both in species and in individuals (your s/s/c is not mine), and of course sapiens as a species has evolved far beyond erectus, both in thinking and in implementing. That does not mean the dualist’s s/s/c depends on your God to provide new neurons and connections BEFORE it can come up with new ideas!

dhw: 1) Why can you accept a few new neurons but not a lot of new neurons as “modification”?
DAVID: Because that is how plasticity is described in the literature.
dhw: Plasticity is simply the ability to change, to be shaped or moulded, to adapt…I don’t know of any definition of plasticity that places a limit on the number of cells that can be changed.
DAVID: My answer is above. Plasticity allows a few new neurons in the research done. It is mostly connectivity.

That is because you cannot do research on living brains a million years old, and the modern brain has stopped expanding. It complexifies through new connections (and has shrunk because of the efficiency of complexification). It is a fact that brains expanded in stages. This is just as true of your hypothesis as of mine, and so a million years ago brains must have been plastic enough to allow for lots of new neurons.

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dhw: The point in dispute here is not dualism but your continued insistence, directly contradicting your dualistic beliefs based on NDEs, that the s/s/c cannot THINK without a functioning brain!
DAVID: Of course it thinks when separated from the body, but when it returns and is attached to the brain and the revived person receives its knowledge through the brain. A living person can reach his s/s/c only through his brain. The s/s/c has a role with the brain and separate from the brain. Dualism.

The s/s/c IS the person. A dead body has lost the attributes that made it a person. It is the s/s/c that had the experience and informs the revived brain. The soul/self doesn’t “reach” the soul/self through the brain. In dualism, as above, the soul/self IS itself, and instructs the brain! THAT is its dualistic role with the brain when the brain functions.

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dhw: We are talking about advances in evolution. The pauses (stasis) take place when organisms have what they need to survive. The advances take place when (a) their survival is threatened, and (b) when individuals come up with new ideas that will IMPROVE chances of survival or IMPROVE modes of living.
DAVID: Improvement is answered in the other thread. I think the emphasis is complexity as explained there. Each stage of an enlarged brain allowed pre-sapiens to develop a better way of living, but it required the enlarged brain for each advance.

Improvement is dealt with under “automaticity” and "reptile". I’m glad you acknowledge its importance(“better way of living”). And yes,these advances could not have been implemented without the enlargement of the brain. The question is whether it was enlarged before concept and implementation or as a result of implementation. You say you are “happy with God speciating each stage of enlarged brain”. I don’t want to spoil your happiness. But let me point out that all our observations suggest that brain modifications occur as a result of implementing new ideas, and not in advance of implementation.

dhw: You accept that new actions cause “modifications” to the brain. Enlargement is a modification. By all means reject the hypothesis on the grounds that we have no evidence (just as we have no evidence that your God enlarged the brain before the new actions were performed), but there is no reason to reject it on the grounds that enlargement is not a modification.
DAVID: You are playing games with the word 'modification'. Enlargement and cortical complexity are specific modifications, which I think God supplied.

I’m afraid it was you who played games by claiming that only complexification, plasticity and shrinkage could be called “modifications”. Thank you for now accepting that enlargement is also a modification, and since you agree that new actions cause modifications, it is not unreasonable to propose that in the distant past new actions caused enlargement, even if the very idea makes you unhappy.