Brain complexity: learning new tasks (Introduction)

by dhw, Saturday, December 02, 2017, 14:15 (2548 days ago) @ David Turell

dhw: … I offered the concrete, non-nebulous example of tool-making. According to you, God expanded the brain and then bigger-brained hominin thought of tool-making. But also according to you, conceptualization has nothing to do with the size of the brain, because it is the “soul” that conceptualizes,
DAVID: This is where we are very apart. The soul uses the brain to create concepts.

“Create” is not clear. The (dualist’s) “soul” creates the concepts, and the brain implements them.

DAVID: Consciousness thinks using the hardware of the brain, and consciousness is the software. I've brought up this analogy many times, but you skip over it. As new uses of the existing brain are attempted, the brain has the capacity to change itself plastically, enlarges and then as it completes its transformation it shrinks with new complexity.

The software uses the hardware of the computer to implement its concepts (“thoughts”, if you insist on this unhelpful analogy). The hardware does not produce the concepts. Consciousness uses the brain to implement its concepts. The brain does not produce the concepts (unless you believe in materialism, but that is a different discussion which I will eventually re-open.) End of analogy, which merely repeats my point. Yes, the brain has the ability to change itself plastically, i.e. to expand, contract, complexify. In sapiens, it has shrunk thanks to the efficiency of complexification. In pre-sapiens it kept reaching points at which it had to expand, and since it already had that ability, it did not need God to do the expanding. (But he may have designed the ability.)

DAVID: All we have as evidence is in our brains with the process I describe above only occurring in the same size brain and skull. Our very civilized concept filled brains and skulls are smaller than 300,000 years ago. All because we received an extra 200cc 300,000 years ago, long before any of our current concepts were envisioned. Your view is so contorted.

Once more: modern science shows that the brain changes in RESPONSE to new concepts. Our brains expanded 200cc 300,000 years ago, but (presumably) could not expand any further without unbalancing the body. So of course that last expansion preceded all subsequent concepts, because from then on, in its response to new concepts, the brain complexified more and more efficiently instead of expanding. In pre-sapiens the brain continued to expand because it kept reaching a point when complexification could not fulfil the demands. This would also have been the case in your own scenario, since your God would have expanded the brain for the same reason. But you have him doing it BEFORE new concepts made it necessary, whereas I have hominins doing it WHEN it was necessary, i.e. in response to new demands, as proven by modern science. The contortion is yours.

DAVID: I've explained expansion/contraction within a given size and have not ignored the known science. That I view God as having gifted each stage of hominin with a new brain size for subsequent use, is something you cannot accept. And that view is obviously supported by the artifacts produced after that size appears.

Once more: I do not accept it because the known science (and common sense) tells us that the brain changes as a RESULT of the effort to implement new concepts, whereas you argue that it expanded BEFORE the new concepts existed. This is only true of sapiens’ brain, which stopped expanding and instead responded to new concepts by rewiring itself. The rewiring does not precede the new concepts. With pre-sapiens, once complexification had exhausted its abilities, the implementation of the new concept (artefact) would only appear when the brain had finished changing itself (i.e. expanding). And so of course the artefacts are only found alongside the hominin whose brain had finished changing itself.

DAVID: Your hunt for a conceptualizing force that creates 200cc jumps in size of course brings up the issue of how speciation occurs. Since my view is that it is with God's help or intervention we remain far apart. Your common sense is not my common sense.

Speciation is indeed the wider issue. For me it is common sense that if the brain is known to change in the course of implementing a concept, it would not have changed before the concept existed (bearing in mind that in sapiens the permanent change is not expansion but rewiring, as illustrated by the illiterate women learning to write). For me it is likewise common sense that all organisms change as a RESULT of new demands or opportunities: e.g. fins, legs, lumbar adjustments RESULTED from pre-whales entering the water, fish moving to dry land, hominins descending from the trees, rather than the changes appearing before these actions took place. None of this precludes the existence of your God, so theism versus atheism is not an issue here.