No 21, Posted by fw, June 13, 2010
Continuing with excerpts from the You Tube video Part 2, which you can watch below at the end of this post or on You Tube at UBC Ecologist Bill Rees Part 2
Let’s pick-up where we left off — the end of my Pt 3 blog post. Bill Rees has revisited his opening, engaging question: “In the face of the evidence, and our non-response to it, how can we claim to be intelligent?” Good question. Does Rees have a good answer?
It’s our brain, stupid. Or is it our stupid brain?
“And the question then arises, why is this? If we’re all of those things, if we have all these unique qualities as humans and yet fail to respond to evidence that our own action is putting us at risk, what’s going on here? And so perhaps naturally enough as a biologist, I fall back on my biological roots. . . . Human beings are products of evolution. The human brain is a product of human evolution. . . . Most of our instinctive behaviours derive from the brain. So given that we’re are much a product of evolution as a slime mould, there’s no reason to think that nothing in human affairs makes sense except in the light of evolution.”
“I’m not for a moment saying that it’s the only quadrant in which we can extract valuable information to explain human affairs. But it’s something that we don’t think of. So what I want to do is to at least open the possibility that in what we are observing, this disconnect between what we claim to be and the way we act may in fact reside in something that we aren’t conscious of precisely because we tend not to want to think of ourselves as just another species. It’s an insult to people to think that they are merely an animal.”
Two premises underpin Rees’ view of human evolution:
“Premise 1: H. sapiens is an evolved species. Human evolution, including the evolution of human nature, has been shaped by the forces of natural selection. Nothing in human affairs — including much of economic and social behaviour — makes sense except in the light of evolution. However, human evolution is determined as much by sociocultural factors (memes) as by biological factors (genes).”
“Premise 2: Human evolution is incomplete. H. sapiens is a work in progress. The human brain is in transition.”
“Now the second premise here is that we think of ourselves at the pinnacle of evolution but we’re just part way there. We are continuing to evolve as are all other species. We’re incomplete. We’re not perfect. We aren’t completely intelligent. We’re not completely instinctive. We’re in transition between a species controlled almost automatically by the impulses that are innately acquired and in that way a very primitive organism, a lizard or a snake might primarily act out of instinct.
<At this point, Part 2 of Rees’ You Tube video ends. So from this point on my selected transcribed excerpts of Rees’ talk are drawn from UBC Ecologist Bill Rees Part 3.>
Triune brain complicates human self-conscious understanding
“If we can look at the structure of the human brain there is some purely physical evidence of what I’m suggesting here. One of the most, I suppose, dramatic expressions of this came to us from Paul McLean about two or three decades ago. He proposed the human brain is a ‘triune’ organism. It’s not as simple as this, but in general his thesis has proved to be quite robust to tests. And what we can argue from this thesis is that there are three large sub-components of the brain, each with its own kind of intelligence.”
“The reptilian brain stem at the very bottom here [points to brain stem] is old brain. Now keep in mind that human beings are a species of vertebrate organism that shares in its personal development or ontogeny the same kinds of transition states as do other organisms that are vertebrate animals. And as the human organism evolved over time we obviously had to start from where we were. So at one point, when we were much closer to reptiles, the brain basically had that structure. When mammals evolved they added to that structure. They didn’t abandon the instinctive centres of the brain. Down here [points to brain stem] is where all the automatic functions take place. You’re not conscious of having to breathe. You don’t control your heart rate. It’s all taken care of for you auomatically down there as it is in much more primitive organisms.”
“As mammals evolved they acquired this middle brain where our limbic system resides. This is the seat of our emotions and our affection for one another. The feelings, responses to food, sex and so on and so forth.”
“Humans have added more than any other organism — something called the neocortex, the third great layer as it were. And this is the seat of our intelligence, our capacity for forward planning, our capacity for compassion, the thought centres, the language centres and all those so-called higher functions that we exhibit to a much greater extent than any other organism.”
“So in many respects humans have three brains, all operating at the same time, each influencing the other in a very tightly integrated way so that at any point in time you may not even be conscious of which part of that brain is actually in control of your actions.“
End of Part 4