Big brain evolution: brain size and intelligence (Evolution)

by dhw, Saturday, April 21, 2018, 10:32 (2407 days ago) @ David Turell

DAVID: The brain cannot plan for implementation without thought. So, please define your use of the word 'implementation' as it relates to brain function. For the argument about brain size, it is important to know where thought and actions take place. The s/s/c is compartmentalized in its interface with the brain, a concept you struggle with.

dhw: Planning is thought, and once again you are talking of WHERE thought and actions take place, but that does not mean the brain does the thinking/planning! As usual, you are dodging the issue of your own dualism. All you are saying is that the thinking "soul" operates within different areas of the implementing brain. You know perfectly well what is meant by implementation, since you gave a model description of it yourself in relation to making the spear. [I repeated the details.] As with the examples we know through modern science, these new actions will require changes to the brain. In sapiens the direct changes are not shrinkage but complexification and in some cases limited expansion.

DAVID: Cro-Magnons are sapiens!!! Their brain was 150 larger! Why are you ignoring a major scientific finding? It is obvious complexification can shrink a brain.

First you say the brain does the planning (as if planning was not thought), you give the soul a location as if that negated its function as the source of thought, then you ask me to define implementation, which I do, and now you ignore all that to tell me what I have been telling you for months: we know the brain of sapiens has shrunk, and I am the one who has proposed that the shrinkage is due to the efficiency of complexification!

DAVID: Cro-Magnons show advanced thought shrinks a brain, not the opposite effect.

Cro-Magnons show that over the last x thousand years, the sapiens’ brain has shrunk. You have just agreed that it is material complexification (not immaterial thought) that shrinks the brain, and complexification, as modern science has demonstrated, is caused by IMPLEMENTATION of thought. But by focusing on shrinkage, you are ignoring the whole context of our discussion, and so yet again let me try to summarize the context and the sequence from expansion to shrinkage:

1 Facts: a) pre-sapiens’ brain expanded; b) sapiens’ brain has shrunk; c) implementation of thought causes brain changes (complexification and limited expansion) in sapiens; d) sapiens’ thought has made major advances during the last x thousand years.
2 You agree a) that in dualism the “soul” (software) does the thinking and interacts with the brain/body (hardware), which does the implementing; b) complexification has caused shrinkage in sapiens.
3 dhw’s dualistic hypothesis: a) pre-sapiens “soul” thinks up new concept; implementation of concept requires additional brain cells and connections. Brain expands; b) brain/skull reach maximum practical size in sapiens; “soul’s” thoughts now implemented by complexification and limited expansion of particular sections; c) process of complexification so efficient that sapiens’ brain no longer needs certain cells and connections, and shrinks.
4 All advances in thought must begin with individuals. Every stage in pre-sapiens human evolution continued for hundreds of thousands of years without significant advances until someone came up with new ideas which required brain change (expansion). Sapiens continued for hundreds of thousands of years until someone came up with new ideas which required brain change (see 3 b and c). The pattern is consistent.

Please tell us what you object to.