When Sagan takes on himself the task to explain to the general public how our brain works, the result is "Dragons of Eden" - an exciting tale of the state-of-the-art in brain research, human psychology, mental diseases, evolution, intelligence (both in humans and animals), dreams and speculations about various uncovered issues, including extra-terrestrial intelligence.
I have only good things to say about this book. It has the two qualities that make a book a great reading - (1) fluid readability, (2) interesting content that teaches me stuff I didn't know before. It has another trait - especially important for me - it touches many topics that I have a great interest in, and expands my views and knowledge on these topics - and for this I'm *very* grateful to the author.
Being very interested in evolution, I found the parts of the book that talk about the evolution of the brain breath-taking. The meaning of the evolution of extragenetic intelligence (brains in animals and humans) and extrasomatic intelligence (books, computeres) in humans, the nature of instincts buried in our "reptile brain" regions, the conflict between the left and right neocortex and the purpose of each, this is exciting stuff !
As an utterly rational being, I always look for ways to prove to myself that rationality is more important than emotionality. In one of the chapters of this book, Sagan gives me a valuable clue - the emotional parts of our brain evolved much earlier than the rational, and are common to most mammals. But what really sets the human different from other animals is the evolution of the big neocortex with the rational side of thought. The rational won the evolution was against the emotional - homo sapiens rules this planet, after all.
Will the next evolutionary step be a complete detachment of our mind from the primate emotional instincts, and reliance only on the rational, more advanced brain ? Funnily, this is very alike Artificial Intelligence. I just wonder what arrives first...
Sagan did an extraordinary job with this book, and I certainly like his writing a lot - I liked "Cosmos" but this book is even better. I'm impressed of how much diverse, interesting and mind-opening information about so many topics is packet in 250 small pages. Luckily I have another of his books on my shelf waiting in the read-queue :-)
P.S. Carl Sagan was an astronomer, so evolution and brain-structure wasn't exactly his main area of expertise (a fact he mentions in the book preface / acknowledgements). And still, he wrote this book and got the Pulitzer prize for it. Fully deserved, I'm awed at the quality and clarity of his writing. Reading his books makes you want to be a scientist...