Carl Sagan, "The Dragons of Eden"

 

 

Carl Sagan, "The Dragons of Eden: Speculations

on the Evolution of Human Intelligence" (1977)

 

 

집 떠나서 마침 읽을 거리도 거의 다 떨어진 판에 이 책을 서울 도서관에서

빌려 읽게 된 것은 우연이었다. 그러니 행운이었다. 재밌게 읽었다.

저자가 특별히 하고 싶어하는 듯한 말에 나도 공감한다.  이 책을

언제 또 만나게 될지 몰라서 좀 많이 인용해 놓는다. 

 

요 아래 인용한 한 구절(p 81-82)을 읽으면서는, 전에

머리를 스쳤던 생각이 다시 떠오르기도 했다:

예의 바른 사람보다는 진실한 사람을!

 

While our behavior is still controlled by our genetic inheritance, we have, through our brains, a much richer opportunity to blaze new behavioral and cultural pathways on short scales... In addition, human beings have, in the most recent few tenths of a percent of our exsistence, invented not only extragenetic but also extrasomatic knowledge: information stored ouside our bodies, of which writing is the most notable example. (p 3-4)

 

"We are a scientific civilization," declared Jacob Bronowski. That means a civilization in which knowledge and its integrity are crucial. Science is only a Latin word for knowledge... Knowledge is our destiny. (p248, 책 본문 끝 구절)

 

This would mean that new learning corresponds to the generation of new synapses or the activation of moribund old ones. (p 47)

 

MacLean has developed a captivating model of brain structure and evolution that he calls the triune brain. "We are obliged," he says, " to look at ourselves and the world through the eyes of three quite different mentalities," (p 57)

 

The brain of a human fetus also develops from the inside out, and, roughly speaking, runs through the sequence: neural chassis, R[eptilian]-complex, limbic system and neocortex. (p 60)

 

It is precisely our plasticity, our long childhood, that prevents a slavish adherence to genetically preprogrammed human behavior in human beings more than in any other species. But if the triune brain is accurate model of how human beings function, it does no good whatever to ignore the reptilian component of human nature, praticularly our ritualistic and hierarchical behavior... (... I also wonder whether the frequent ritualistic behavior in young children is a consequence of the still incomplete development of their neocortices). (p 64)

 

[I]t seems a useful first approximation to consider the ritualistic and hierarchical aspects of our lives to be influenced strongly by the R-complex and shared with our reptilian forebears; the altruistic, emotional and religious aspects of our lives to be localized to a significant extent in the limbic system and shared with our nonprimate mammalian forebears (and perhaps the birds); and reason to be a function of the neocortex, shared to some extent with the higher primates and such cetaceans as dolphins and whales. While ritual, emotion and reasoning are all significant aspects of human nature, the most nearly unique human characteristic is the ability to associate abstractly and to reason. Curiosity and the urge to solve problems are the emotional hallmarks of our species; and the most characteristically human activities are mathematics, science, thechnogy, musuc and the arts -- somewhat broader range of subjects than is usually included under the "humanities." Indeed, in its common usage this very word seems to reflect a peculiar narrowness of vision about what is human. Mathematics is as much a "humanity" as poetry. Whales and elephants may be as "humane" as humans. (p 81-82)

 

A superior agreement is found in the metaphor for the human psyche in Platonic dialogue Phaedrus. Socrates likens the human soul to a chariot drawn by two horses--one black, one white--pulling in different directions and weakly controlled by a charioteer. The metaphor of the chariot itself is remarkably similar to MacLean's neural chassis; the two horses, to the R-complex and the limbic cortex; and the charioteer barely in control of the careening chariot and horses, to the neocortex. (p 83)

 

Human intelligence is fumdamentally indebted to the millions of years our ancesters spent aloft in the trees. (p 87)

 

The development of human culture and the evolution of those physiological traits we consider characteristically human most likely proceeded--almost literally--hand in hand: the better our genetic predispositions for running, communicating, and maniplating, the more likely we were to develop effective tools and hunting strategies; the more adaptive our tools and hunting strategies, the more likely it was that our characteristic genetic endowments would survive... Sherwood Washburn... has said: " Much of what we think of as human has evolved long after the use of tools. It is probably more correct to think of much of our structure as the result of culture than it is to think of men anatomically like ourselves slowly developing culture." (p 103)

 

In 1949, the American anthropologist Leslie White stated unequivocally: "Human behavior is symbolic behavior; symbolic behavior is human behavior." What would White have made of Washoe, Lucy and Lana? (p 121)

 

[Ciimpanzees (Washoe, Lucy and Lana) and Ameslan (p 118-121):

 

   -- 100 - 200 words

   -- inventive in the construction of new words.

 

    duck =>water bird, orange => orange apple, watermelon => drink fruit,

    dirty monkey.

 

An example of a cultural tradition among the mokeys: Imo and wheat grains on a sandy beach. (p 125-126) ]

The other kind of knowing, our nonverbal perceptions and cognitions, is often described as "intuitive."... But intuitive knowledge has an extremely long evolutionary history... it goes back to the origin of life... Rational thinking that is fully verbal (involving complete sentences, say) is probably only tens or hundreds of thousand years old. There are many people who are, in their conscious lives, almost entirely rational, and many who are almost entirely intuitive. (p 166)

 

Such observations strongly suggest that those functions we describe as "ratinal" live mainly in the left hemisphere, and those we consider "intuitive," mainly in the right. (p 167)

 

the difficulty of describing verbally the complex perceptions of the right hemisphere. (p 174)

 

There is no way to tell whether the patterns extracted by the right-hemisphere are real or imagined without subjecting them to the left-hemisphere scrutiny. on the other hand, mere critical thinking, without creative and intuitive insights, without the search for new patterns, is sterile and doomed. To solve complex problems in changing circumstances requires the activity of both hemispheres: the path to the future lies through the corpus collosum. (p191)

 

[C]reating the mathematics and physics is more of a right-hemisphere function than teaching it... Major scientific insights are characteristically intuitive, and equally characteristically described in scientific papers by linear analytic arguments... The creative act has major right-hemisphere components. But arguments on the validity of the result are largely left-hemisphere functions. (p 193)

 

It was an astonishing insight by Albert Einstein, central to the theory of general relativity, that gravitation could be understood by setting

the contracted Riemann-Christoffel tensor equal to zero. (p 193)

 

Russell commented that the development of such gifted individuals [polymaths] required a childhood period in which there was little or

no pressure for conformity, a time in which a child could develop and pursue his or her own interests no matter how unusual or bizarre. (p202)

 

[A] famous story told both by Plutarch and P;iny: A dog , following the scent of its master, was observed to come to a triple fork in the road.It ran down the leftmost prong, sniffing; then stopped and returned to follow the middle prong for a short distance, agian sniffing and then turning back. Finally with no sniffing at all, it raced joyously down the right-hand prong of the forked road. Montaigne, commenting on this story, argued that it showed clear canine syllogistic reasoning. (p 221)

 

[L]ong before Montaigne, St. Thomas Aquinas attempted unsuccessfully to deal with the story. He cited it as a cautionary example of how the appearance of intelligence can exist where no intelligence in fact present. (p 221)

 

["Out of sight, out of mind"를 중국어로 번역한 컴퓨터에게 그걸 다시

영어로 번역하랬더니: "Invisible idiot." (p 222 에 있는 이야기)]

 

The brains of extraterrestrials will probably have several or many components slowly accreted by evolution, as ours have. There may still be a tension among their components as among ours, although the hallmark of a successful, long-lived civilization may be the abilty to achieve a lasting peace among the several brain components. (p 244)