Introducing the brain: half a brain is just fine (Introduction)

by dhw, Sunday, March 08, 2020, 11:08 (1719 days ago) @ David Turell

DAVID: As for ancient brains, yes they operated in similar ways, perhaps less complex ways, but this means any new uses made tiny enlargements in those brains just like our brain does.

dhw: Nobody knows why earlier brains expanded. From the known fact that the modern brain makes “tiny enlargements”, I have extrapolated the theory that in former times the brain was able to make large enlargements. Please tell us any known facts that make this impossible.

DAVID: Nothing makes that daydream impossible. It is an extrapolation as you state, but that tiny known enlargement from learning is to learn something already known. What you add is the struggle to develop a new concept makes a brain jump 200 cc in size. The only enlargement we know relates to learning, nothing more. Your extrapolation is really mixing apples and bagels.

Your reference to Einstein made it clear that we don’t know whether his original “thinking/conceptualizing” caused the thickening, or was the result of an inborn thickening. “No real evidence”, you wrote. All we know for a fact is that new activities RESULT in the brain complexifying or enlarging (on a small scale). If it can enlarge on a small scale now, it is not unreasonable to suppose that in earlier times, when the whole organism could adapt to carrying a larger brain, the same process would have taken place. You continue to ignore my plea for the extra knowledge you have that indicates the brain functioned differently in the past.

dhw: I use “cellular intelligence” (possibly designed by God), not “somehow” to explain the gaps. I would say it is more logical to assume continuity than a complete break that requires your God to step in every time he wants to design a new form of homo as he dabbles his way towards the only homo he actually wants to design.

DAVID: If God is doing his job there is full continuity. God doesn't jump in and out discontinuously. Your thinking about God continues to be inconsistent as each problem about God is presented.

You keep insisting that each expansion is a jump engineered by your God. A jump suggests discontinuity. And so if the earlier smaller brain did not expand into the later larger brain as a result of the smaller brain’s activities, you have discontinuity. Also exemplified by the theory of random mutations.

DAVID: I find your theory as weaker and weaker.

dhw: […] please pinpoint anything in the article or in your own “knowledge” that makes my theory illogical or “weaker and weaker”.

DAVID: All the articles I've read from Archaeology give the impression they think the larger brained fossil made the new artifacts they find with the fossils. They do not explain the jump in brain size.

Of course they don’t. And of course the larger brained fossil made the new artefacts. In my theory, the new artefact (we are talking about the first one – not those made subsequently) could ONLY be made if the brain expanded. But there is no way of knowing whether the CONCEPT preceded the expansion (my theory) or followed it (your theory). For clarity’s sake: in my theory, it is the implementation of the concept that causes the expansion – just as the modern brain changes in RESPONSE to new activities and not before them.

DAVID: it is only your nebulous concept the habilis conjured up a new design tool or weapon and blew up the size of his brain so Erectus would appear and could finally make it. That is exactly how your theory translates, totally strange.

There is nothing nebulous about it, except that this concrete example is offered only to illustrate the process – I am not saying the habilis brain thought of a spear and this led to the erectus brain. Nobody knows any of the details. But if we follow this example (originally mine, but you took it up), your description is ridiculous. He didn’t blow up the size of his brain so erectus could make the spear. It was the effort to make it that caused the habilis brain to expand to erectus size. Yet again: the modern brain changes itself through its efforts to meet new demands. I propose that the ancient brain did the same. I ask you for evidence that the ancient brain did not do the same, and you never answer.