Evolution and humans: big brain size or use (Evolution)

by dhw, Saturday, May 20, 2017, 09:12 (2743 days ago) @ David Turell

DAVID: I don't know why you don't understand the concept of the brain as a receiver. When the brain cannot function, as in an NDE, it stops receiving consciousness, which returns when it can receive it. The brain uses consciousness as a function to work with.

Of course I understand it, and if the brain is a receiver, it does not generate concepts (see below) – it receives them! You keep ignoring your own belief in an afterlife in which you survive as your conscious self without your brain. If you are YOU without a brain, it makes no sense to argue that the brain USES your consciousness (= YOU). It has to be the other way round.

DAVID: I don't see that Wiki disagrees with me.
dhw: …it contradicts your claim that development of brain size was NOT gradual (no “itty bitty changes”).
DAVID: Where is it mentioned that each hominin brain vault size doesn't show significant enlargement in each stage?

When it says that the history shows “a gradually bigger brain…during the evolutionary path from early primates to hominids and finally to Homo sapiens”, I presume it means an enlargement at each stage.

DAVID: In my dualist view the enlarged brain allows for further exploration and development of use of functions allowed by consciousness.

What do you mean by “functions allowed” by consciousness? In my view, whether dualist or materialist, it is consciousness that invents (not allows) the functions and instructs (not allows) the brain to perform them.

DAVID: My 'self' forms within my consciousness as I use it. In the infant it starts as a tabla rasa, totally blank except for muscular controls and automatic instincts, suckling, breathing pooping, etc. Size of brain allows expanded use of consciousness. Size of consciousness cannot be considered. It is not material. Each new size in the human evolution allowed much larger conceptualizations to be achieved. Human brain size is 200,000 years old, but use of consciousness now is much larger than at that time. Just consider the appearance of language, only 50,000 years ago, as one supreme example.

I agree with most of this.Obviously the expanded brain is necessary to perform the tasks invented by consciousness, and language is indeed a prime example. Did the need for better communication engender the changes in the anatomy, or did the changed anatomy engender the need for better communication? You have summed up the relationship between brain and consciousness yourself: “Each new size in the human evolution allowed much larger conceptualizations to be achieved.” (My bold) Did larger conceptualizations cause the new size in order to attain achievement, or did the new size cause the conceptualizations? If you believe that the brain is the RECEIVER of concepts, which are the PRODUCT of a consciousness that can exist independently of the brain (as per NDEs), I don’t see how at the same time you can believe that consciousness depends on a larger brain to enlarge its concepts. Enlarged concepts therefore give birth to the enlargement of the tool that implements them (the brain), just as the concept of digging leads to the spade. And so in your dualist scenario, consciousness uses the brain, and not the other way round.