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What is the missing ingredient -- not genes, not upbringing -- that shapes the mind?
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What is the missing ingredient -- not genes, not upbringing -- that shapes the mind?
Genes account for about only about half of the variance in personality and intelligence. Environment doesn't fully account for the rest. As with Bob Dylan's Mister Jones, something is happening here but we don't know what it is, says Steven Pinker in a response to Edge publisher/editor John Brockman's request to futurists to pose "hard-edge" questions that "render visible the deeper meanings of our lives, redefine who and what we are."
Originally published January 2002 at Edge. Published on KurzweilAI.net January 21, 2002. Read Ray Kurzweil's Edge question here.
We know that genes play an important role in the shaping of our personality and intellects. Identical twins separated at birth (who share all their genes but not their environments) and tested as adults are strikingly similar-though far from identical-in their intellects and personalities. Identical twins reared together (who share all their genes and most of their environments) are much more similar than fraternal twins reared together (who share half their genes and most of their environments). Biological siblings (who share half their genes and most of their environments) are much more similar than adopted siblings (who share none of their genes and most of their environments).
Many people are so locked into the theory that the mind is a Blank Slate that when they hear these findings they say, "So you're saying it's all in the genes!" If genes have any effect at all, it must be total. But the data show that genes account for about only about half of the variance in personality and intelligence (25% to 75%, depending on how things are measured). That leaves around half the variance to be explained by something that is not genetic.
The next reaction is, "That means the other half of the variation must come from how we were brought up by our parents." Wrong again. Consider these findings. Identical twins separated at birth are not only similar; they are "no less" similar than identical twins reared together. The same is true of non-twin siblings -- they are no more similar when reared together than when reared apart. Identical twins reared together -- who share all their genes and most of their family environments-are only about 50% similar, not 100%. And adopted siblings are no more similar than two people plucked off the street at random. All this means that growing up in the same home -- with the same parents, books, TVs, guns, and so on -- does not make children similar.
So the variation in personality and intelligence breaks down roughly as follows: genes 50%, families 0%, something else 50%. As with Bob Dylan's Mister Jones, something is happening here but we don't know what it is.
Perhaps it is chance. While in the womb, the growth cone of an axon zigged rather than zagged, and the brain gels into a slightly different configuration. If so, it would have many implications that have not figured into our scientific or everyday way of thinking. One can imagine a developmental process in which millions of small chance events cancel one another out, leaving no difference in the end product. One can imagine a different process in which a chance event could derail development entirely, making a freak or monster. Neither of these happens. The development of organisms must use complex feedback loops rather than blueprints. Random events can divert the trajectory of growth, but the trajectories are confined within an envelope of functioning designs for the species defined by natural selection.
Also, what we are accustomed to thinking of as "the environment" -- namely the proportion of variance that is not genetic -- may have nothing to do with the environment. If the nongenetic variance is a product of chance events in brain assembly, yet another chunk of our personalities and intellects would be "biologically determined" (though not genetic) and beyond the scope of the best laid plans of parents and society.
Copyright © 2002 by Edge Foundation, Inc.
www.edge.org
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Who we are beyond nature vs. nurture
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Obviously, the attempt to limit explanations and definitions of who we are to only our own genes and nuture has not proven entirely satisfactory. I blieve that part of the reason is that we have elected thus far to ignore the host of microorganisms with DNA very similar to our own, including a few identical genes we share in common. I submit that such hosted microbes have natures and nurtures of thier own, independent from our own, to which they respond by expressing those self same genes. I am suggesting that a gene expressed for acetylcholine by some microbe we host, irrespective of the fact that acetylcholine may have a vastly different function in terms of that particular microbe's needs, makes no distinction between the acetylcholine cell binding sites of the microbe and our own.
As well, conceivably, there can be, and probably are, wars and competitions between our hosted micorbes, in which case our own sacred bods are mere war zones on some internacene microbe war. The "biochemical" consequences of such wars are certain to have an effect on the quantity of chemicals which bind to our own sacred cells, and therefore, to a degree, our "quality of life" as well as its quantity perhaps.
My bottom line suggestion: we, as human beings, are not merely the sum of our own nature and nurture, but are the sum of not only that but also
the sum of the microbes/micororganisms which we
invariably host at any one time. Know thy self? Hardly, rather know thy self in terms of all the contributors to that self, including the contribution made by passive or waring microbes.
In short, we are what we host ... or whatever microbes choose to make reservations in our very own genetic hotel.
If I were god, and I'm not a candidate for that office just now, I would not speak to any of my creation from burning bushes and such. After all, what language would I use exactly? Rather, I would wrap my message in a nice neat DNA or RNA universal language packet and trundle it off. I might even deliver it via some viral waystation or microbial UPS ... something on the order of how Bill Gates delivers software instructing computers how to crash more often and more efficiently. :-)
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Re: What is the missing ingredient -- not genes, not upbringing -- that shapes the mind?
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I agree (nearly) completely. Especially on the notion of similarity, which Pinker obviously measures in terms of variability.
It not only violates statistical principles, it is, if it is allowed to speak with L.Wittgenstein, free of any meaning (i.e. not wrong, it falls outside the category of correct or wrong)
Complex systems depend on the irreducible triadic relation between self (observer),the other (the observed), and the signal (sign) exchanged. This relation is the reason for strong differences in outcome for nearly identical starting points (theory of complex systems, edge of chaos, amplification of infinite small differences, etc.)
Asking about external reasons only is hopelessly reductionistic.
Klaus
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Re: What is the missing ingredient -- not genes, not upbringing -- that shapes the mind?
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Re: What is the missing ingredient -- not genes, not upbringing -- that shapes the mind?
Without having even read this piece, I will dare to answer your question. The answer is perception. You can have the same genes, the same upbringing and yet still perceive things differently. This can shape how you evolve as an individual.
For example take 2 identical twins who grow up in the same environment. So assume nature and nurture are basically the same, although in reality, there are subtle differences that can emerge over the evolution of each twin.
Also, identical twins may have different neurological development. One may have got more nutrients in the embryo etc.. bla bla.. so really nature and nurture are often only seen skin deep.
But assuming all was equal in both nature and nurture with 100% duplicity, then why does perception differ ? Well because perception is often based on incomplete information. Sometimes based on mere chance either in terms of nature or nurture.
Even though two twins may share exactly the same genetic blue print to the nth degree, the subtle forces of nature could effect the individual experience at the most elemental level. From here the effect can be compounding as each individual evolves and the effects of their perceptions are also compounded and hence their judgements and actions. Some outcomes result in better survival opportunities than others and hence better evolution opportunities.
Anyway that's my view, until I get another view.
Regards,
Dave
9 Sep 2002
PS
How do I know this to be true you may well ask? Well I spoke to some Aliens who told me it was true. I guess I believed them, as they seemed smarter than me. But they were nice Aliens. They even offered me a cup of tea and scones.
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Re: What is the missing ingredient --cup of tea and scones
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Dave,
The "Turing Test" was formulated long ago, and although it might well be improved upon, If you *really* think about it, it can be a good test for intelligence if you make it so.
Canned responses will get old rather quickly, and even with a huge store of minor variations, it is more the "appropriateness" of the response that counts.
If we stick to "text responses only", suppose you and I are having a "live chat", and in the middle of a response about global warming, I "interrupt myself" to say, "Uh-Oh, the gf is home from work." If you were the AI, you would need to:
a) Know "gf" meant "girlfriend".
b) Understand that "home from work" means she is now present at my locale (else, how would I know she was home? Perhaps I just read about it in the newspaper?)
c) Understand that my "Uh-Oh" implies that I might get in trouble for being on the computer. Why would this seem "natural" to you, unless you somehow understood that spouses can sometimes be "touchy" about sharing time with others, espacially via the "great anonymous internet".
d) Remember if I had previously said something like, "I share a house with Sally, and she is at work" (whatever "work" is), and then surmise that I was talking about the same person.
So ... a "canned" (or even poorly generated and customized), yet simplistic response like, "Does it trouble you that your girlfriend is home from work?" would seem stiff and unnatural, whereas "Oh, I know how that can be - I better let you go for now", would seem far more human and "understanding".
I could have also made the conversation a bit more "analytically difficult". I might have said, "I share a house with Sally, but she's off balancing the books for a customer this afternoon." And then, later on, I could have said "Uh-Oh, the little accountant is pulling up in the driveway."
Then you would have to properly link "balancing books" with "accounting" (as opposed to balancing them on you head as a posture enforcing exercise) as well as understand that "pulling up in the driveway" means "has arrived at home, where I reside", as well as be sensitive to the other appropriate "human" understandings about feelings and pet-peeves, etc.
Overall, that is an ENORMOUS amount of intelligence you would have to draw upon, in rapid responses, and not "slip up" and say something that would make almost no sense at all.
For a machine to pass a good strong Turing Test, it would need both a huge breadth of "common knowledge", as well as understand the relations between things, subtle nuances of my phraseology that hinted whether I was being sarcastic or humourous or genuine in a particular response, etc.
In 10 years (with a dedicated research-level machine) we may come close to this. In 20 years, I am quite sure it could fool the best of us.
By then, speech synthesis should be advanced to the point that the AI could formulate "natural speech", along with delicate intonements (to indicate that IT was intending sarcasm or humor), and even slurring or "stumbling" over words when it gets into an excited exchange, and try to talk too fast, or interrupt itself in mid-sentence, etc.
Imagine a Turing Test that you could have over the phone.
Of course, it would (likely) not be "feeling" any of the "emotions it was emoting", might not really feel amused or annoyed or excited, but rather "calculate" that this would be the appropriate response at the given moment in order to appear "human-like". So it could be exceedingly "intelligent", and not at all a "sentient being" (as we experinece being sentient and "awake").
That (sentience) might require more that programming and arbitrarily conducted formal calculation. It might actually (I suspect) be a function of how those processes are manifest in a physical substrate.
Cheers! ____tony b____
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