The Dragons of Eden: Speculations on the Evolution of Human Intelligence
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Dr. Carl Sagan takes us on a great reading adventure, offering his vivid and startling insight into the brain of man and beast, the origin of human intelligence, the function of our most haunting legends--and their amazing links to recent discoveries.
"A history of the human brain from the big bang, fifteen billion years ago, to the day before yesterday...It's a delight."
THE NEW YORK TIMES
Shelley, penned the now-famous tale of Dr. Frankenstein’s monster, who is brought to life by the application of massive electrical currents. Electrical devices have been a mainstay of gothic novels and horror films ever since. The essential idea is Galvani’s and is fallacious, but the concept has insinuated itself into many Western languages—as, for example, when I am galvanized into writing this book. Most neurobiologists believe that the neurons are the active elements in brain function,
hand, modern electronic computers are capable of processing information at a rate of 1016 to 1017 bits per second, compared to a peak rate ten billion times slower in the brain. The brain must be extraordinarily cleverly packaged and “wired,” with such a small total information content and so low a processing rate, to be able to do so many significant tasks so much better than the best computer. The number of neurons in an animal brain does not double as the brain volume itself doubles. It
receptive sexual posture. The male beetles enjoy several weeks of orgiastic ecstasy among the orchids, and when eventually the females emerge from the ground, we can imagine a great deal of wounded pride and righteous indignation. Meanwhile the orchids have been successfully cross-pollinated by the amorous male beetles, who, now properly abashed, do their best to continue the beetle species; and both organisms survive. (Incidentally, it is in the interest of the orchids not to be too consummately
global applicability. There is no way to tell whether the patterns extracted by the right hemisphere are real or imagined without subjecting them to 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 cerebral hemispheres: the path to the future lies through the corpus callosum. An example of
note that a friend of mine who has spent time with them says that for such activities as the patient stalking and hunting of mammals and fish they prepare themselves through marijuana intoxication, which helps to make the long waits, boring to anyone further evolved than a Komodo dragon, at least moderately tolerable. Ganja is, he says, their only cultivated crop. It would be wryly interesting if in human history the cultivation of marijuana led generally to the invention of agriculture, and