This was an interesting book to read after all of the recent research and groundbreaking discoveries of the human brain Clearly, Sagan smokes weed However, there are times when he must be coming off his high that his insights are both subtle and poignant Oxymoronic, to be sure, but so was most of Sagan s keen skepticism amidst his psuedoscientific platitudes.I use big words That being said, some of the best parts of this book are the drawings related to studies conducted on patients with a s This was an interesting book to read after all of the recent research and groundbreaking discoveries of the human brain Clearly, Sagan smokes weed However, there are times when he must be coming off his high that his insights are both subtle and poignant Oxymoronic, to be sure, but so was most of Sagan s keen skepticism amidst his psuedoscientific platitudes.I use big words That being said, some of the best parts of this book are the drawings related to studies conducted on patients with a severed corpus collosum If you never read this book, I highly recommend you find it in a bookstore just to check out these studies Here is a slightly less technical version Carl Sagan is a big name, or at least he used to be But other than the series Cosmo or the movie with Jodi Foster, he was known for his speculation in everything In this case, it s consciousness By the title, he s referring to the lizard brain And considering the fact that he was writing this out of the 70 s and he disclaimed the hell out of it, it s meant to be a conversation starter for laymen.All good And it s good, too If I was reading this 40 years ago or even 30 years ago, I d Carl Sagan is a big name, or at least he used to be But other than the series Cosmo or the movie with Jodi Foster, he was known for his speculation in everything In this case, it s consciousness By the title, he s referring to the lizard brain And considering the fact that he was writing this out of the 70 s and he disclaimed the hell out of it, it s meant to be a conversation starter for laymen.All good And it s good, too If I was reading this 40 years ago or even 30 years ago, I d nod energetically at a lot of the ideas The writing is good, the ideas sound, and the subject is still obviously open today.So what did I have a problem with Actually, my complaint is rather prosaic It s just dated HEAVILY dated It s like the line from Hitchhiker s Guide to the Galaxy where Prosser still thinks that digital watches are a good idea.There are better books that do the job of this one, but for the time I m sure it was pretty fantastic Not everything was dated Philosophy and basic math and the broad strokes were good But the fields of mental health, computers and computer games, the current development of cloning, AIs, and a huge extra list WAS.Alas Time marches on Dr Carl Sagan takes us on a great reading adventure, offering his vivid and startling insights into the brains of humans beasts, the origin of human intelligence, the function of our most haunting legends and their amazing links to recent discoveries I d read this book a few years ago, and loved it It s a great introduction to brain anatomy, consciousness subconsciousness, and evolution An easy read, if any book that deals with these types of topics can be considered as such Sagan is good at presenting complex material in an interesting and palatable way It made me want to start payingattention to my dreams He also relates one of his personal experiences of smoking marijuana, and his theories of the effects it might have on the I d read this book a few years ago, and loved it It s a great introduction to brain anatomy, consciousness subconsciousness, and evolution An easy read, if any book that deals with these types of topics can be considered as such Sagan is good at presenting complex material in an interesting and palatable way It made me want to start payingattention to my dreams He also relates one of his personal experiences of smoking marijuana, and his theories of the effects it might have on the brain and consciousness In this Pulitzer prize winning book, Carl Sagan, indubitably one of the finest scientific minds of our time, expresses his thoughts about life, most particularly about intelligent life, and its relation with the environment that gave it origin and shaped it.Aided by anthropological notions, evolutionary biology, psychology, and computer science, Sagan gives a well balanced perspective of how human intelligence evolved However, notwithstanding Sagan s expertise in astrophysics, he warns us that In this Pulitzer prize winning book, Carl Sagan, indubitably one of the finest scientific minds of our time, expresses his thoughts about life, most particularly about intelligent life, and its relation with the environment that gave it origin and shaped it.Aided by anthropological notions, evolutionary biology, psychology, and computer science, Sagan gives a well balanced perspective of how human intelligence evolved However, notwithstanding Sagan s expertise in astrophysics, he warns us that in the neurosciences he sof an amateur scholar than consumed expert That, added to the age of the book, results in much of the book being speculative work Interestingly, some of his assumptions have been latter integrated to the commonly accepted model for the evolution of the human brain.One of my favorite sections of the book takes on the biological function behind human intelligence I particularly like when Sagan considers the complexity of biological life forms, putting in perspective the real significance of our cultural and technological advances Anyone interested in human evolution will find this book exciting The meaning of the evolution of extra genetic intelligence brains in animals and humans and extra somatic intelligence writing, books, computers in humans, the nature of instincts buried in our older reptilian brain regions, the conflict between the left and right neocortex and the purpose of each, this is exciting stuff that we can all see at work in our lives, giving evolution an extra layer of reality.After finishing reading, I was left wondering if the next evolutionary step would imply a complete detachment of our mind from the primate emotional instincts, and reliance only on the rational,advanced brain Is our brain on its way to become alike to Artificial Intelligence I think Sagan did an extraordinary job with this book His writing is engaging and easy to understand, even if you re not too much into the sciency stuff Most impressive is how diverse, interesting and mind opening are the many well informed topics contained in the ca 250 pages of this book Arecent book, Up from Dragons The Evolution of Human Intelligence 2002 coauthor by Sagan and John Skoyles actualizes the concepts and hypotheses first presented in Dragons of Eden But, don t get fooled, Up from Dragons is not a replacement reading to Dragons of Eden, it s a follow up for it will be a shame to miss Sagan s great original prose Chimpanzees can abstract Like other mammals, they are capable of strong emotions.Why, exactly, all over the civilized world, in virtually every major city, are apes in prison Humans have systematically exterminated those other primates who displayed signs of intelligence Carl Sagan is the best science teacher one can ever get Even though I am not a biology major, I was able to enjoy this book A great book where he talks about EVERYTHING that you ever wanted to know about your brain ProbaChimpanzees can abstract Like other mammals, they are capable of strong emotions.Why, exactly, all over the civilized world, in virtually every major city, are apes in prison Humans have systematically exterminated those other primates who displayed signs of intelligence Carl Sagan is the best science teacher one can ever get Even though I am not a biology major, I was able to enjoy this book A great book where he talks about EVERYTHING that you ever wanted to know about your brain Probably one of the best non fictions I have ever read Some info that made me love this book how much info do our genes carry evolution of human brain various components of human brain right and left hemisphere of brains what exactly is intuitiveness why do humans and other mammals sleep difference between dream sleep and dreamless sleep REM sleep what do our dreams mean why do some people sleep for longer time while some sleep for lesser time extraterrestrial intelligence what causes some of the mental illnesses why animals cannot talk Reptiles vs MammalsPulitzer Prize Winner Interesting read, as long as one takes into account that it s quite old and outdated by now, so it s not exactly cutting edge I read it pretty long ago myself.Still, Sagan has a such a pleasant, conversational style, that even reading it for the speculations alone, makes reading the book a not unpleasant way of whiling away your time.I like the angles he chooses to speculate from, especially the bits about instinct and how myths most probably formed in the human collective subconscious. Interesting questions on the origin and development of human intelligence Still worth a read despite lots of progress since he wrote this Gives a good description of left right brain competencies Has piqued my interest in evolutionary development The guy was taken from us too early but sure made a name for himself in what time he had. One of the most beautiful things I ve ever read came from this book If the human brain had only one synapse corresponding to a monumental stupidity we would be capable of only two mental states If we had two synapses, then 2 2 4 states three synapses, then 2 3 8 states, and, in general, for N synapses, 2 N states But the human brain is characterized by some 10 13 synapses Thus the number of different states of a human brain is 2 raised to this power i.e., multiplied by itself ten One of the most beautiful things I ve ever read came from this book If the human brain had only one synapse corresponding to a monumental stupidity we would be capable of only two mental states If we had two synapses, then 2 2 4 states three synapses, then 2 3 8 states, and, in general, for N synapses, 2 N states But the human brain is characterized by some 10 13 synapses Thus the number of different states of a human brain is 2 raised to this power i.e., multiplied by itself ten trillion times This is an unimaginably large number, far greater, for example, than the total number of elementary particles electrons and protons in the entire universe Dragons of Eden by Carl Sagan won the Pulitzer Prize for Non Fiction in 1978Natural selection has served as a kind of intellectual sieve, producing brains and intelligences increasingly competent to deal with the laws of nature.There isn t much discussion of dragons, beyond a short snippet on Komodo dragons, in this book but Sagan uses this metaphor as a catchy title to highlight that this fear may be part of our own mammalian evolution The dragon concept is buttressed by so many old tales thro Dragons of Eden by Carl Sagan won the Pulitzer Prize for Non Fiction in 1978Natural selection has served as a kind of intellectual sieve, producing brains and intelligences increasingly competent to deal with the laws of nature.There isn t much discussion of dragons, beyond a short snippet on Komodo dragons, in this book but Sagan uses this metaphor as a catchy title to highlight that this fear may be part of our own mammalian evolution The dragon concept is buttressed by so many old tales throughout numerous civilizations that Sagan implies there must have been a fearsome dragon or related animal in our distant past that shaped our evolution I am not convinced per se but the rest of the book is muchserious than this topic Carl Sagan is arguably the greatest science writer and educator of recent times In this book his mind, through his theories, is on full display for all to see He steps through various evolutionary ideas about how man and his brain has evolved As has been stated in other reviews of this book, a mark against it is that some sections are now outdated Science evolves Yet, for me, it is remarkable even when discussing a mundane game of Pong that Sagan is able to foresee many of our challenges we face today He even talks about the danger of computers and video games pre empting children from learning the proper fundamentals of math and science As a parent, there is little argument from me on this point At its core this is a thought provoking book that resonates It is short at only nine chapters so I will review the chapters here because many are true gems and the rest are pretty good.Chapter 1 The Cosmic CalendarIn this chapter Sagan famously maps the age of the universe, nearly 14 billion years, into a single year We see that if the Big Bang starts on January 1st at 12 01 am, then humans don t arrive to the timeline until December 31st at 10 30 pm, and all of our recorded history can be confined to the final 10 seconds of the year Powerful stuff.Chapter 2 Genes and BrainsThe average human brain has 10 13 synapses This means there are 2 10 13 possible states of a single brain, a number that approaches the number of atoms in the universe We also learn that The simplest organisms on Earth today have just as much evolutionary history behind them as the most complex In other words even simple diatoms are well honed and efficient machines Chapter 3 The Brain and the ChariotHumans have a very high brain to mass ratio relative to any other animal on the planet Sagan goes on to discuss sleep and posits a theory that land mammals sleep so much because they can hide and are less vulnerable than marine mammals For example dolphins rarely sleep, sometimes only for a minute at a time I will take it a step further and say that land mammals may also sleep so much because it is difficult for most, not all, mammals to find food in the dark Isn t it better to burn as few calories as possible through sleeping those night time hours away Whatever the real reason, this trait goes back to the end of the dinosaur era.Chapter 4 Eden as a Metaphor paleontologists have deduced that bipedalism preceded encephalization, by which they mean that our ancestors walked on two legs before they evolved big brains It seems that hunting developed brains further in this regard Chapter 5 The Abstractions of the Beasts My favorite chapter It s largely about how humans have developed verbal speech and a large part of our oversized brains are dedicated to this function But it also discusses how incredibly smart chimpanzees are and how presumptuous humans are about or lack thereof intelligence in all animals It seems that this view is because they don t have vocal chords Scientists have taught select chimps sign language and they have learned to use words correctly and in context nouns, verbs and adjectives to the tune of vocabularies in excess of one hundred words The chimps can even sign curse words when humans introduce illogical steps into a food reward scheme The average human uses just 1,000 common words in everyday speech and some mentally impaired humans don t even reach that level Sagan implies that due to the chimpanzee s small brain volume it is unlikely they can ever achieve normal human level language However it is clear that chimps and many other animals feel anxiety and think in ways that are muchin line with humans than I ever knew The implication here is that the inability to verbalize word constructs, i.e language, is what has kept other animals from evolving Although dated, this chapter alone is worth the price of the book or a trip to the library.Chapter 6 Tales of Dim EdenThis chapter primarily revisits the topic of sleep first broached in chapter 3 and talks a good deal about dinosaurs Maybe this section should have been combined with The Brain and the Chariot.Chapter 7 Lovers and madmenThis chapter is heavily focused on brain hemisphere functions and the tie in to evolution Very informative M S Gazzaniga of the State University of New York at Stony Brook suggests that hemispheric specialization occurs because language is developed in the left hemisphere before the child acquires substantial competence in manipulative skills and geometrical visualization According to this view, the specialization of the right hemisphere for geometrical competence is a specialization by default the left hemisphere s competence has been redirected toward language Chapter 8 The Future Evolution of our Brain In general, human societies are not innovative They are hierarchical and ritualistic Suggestions for change are greeted with suspicion they imply an unpleasant future variation in ritual and hierarchy an exchange of one set of rituals for another, or perhaps for a less structured society with fewer rituals And yet there are times when societies must change Wow This is such a well articulated statement Most of us recognize this type of change is the fundamental impediment to solving many of our country s problems and by extension in solving the world s environmental and population problems Sagan goes on to wade into the abortion debate as well He also talks about tech and its benefit and possible detriment to children Not a cohesive chapter by any stretch and outdated perhaps, but still thought provoking Chapter 9 Knowledge is our DestinyAn intriguing chapter where Sagan speaks of aliens It is his belief that while their physical forms will be unfamiliar to us, their minds will be similar Organisms throughout the universe should therefore be sensitive to optical and or radio radiation, and, after the development of physics, the idea of electromagnetic radiation for interstellar communication should be a cosmic commonplace a convergent idea evolving independently on countless worlds throughout the galaxy after the local discovery of elementary astronomy, what we might call the facts of life If we are fortunate enough to make contact with some of those other beings, I think we will find that much of their biology, psychology, sociology and politics will seem to us stunningly exotic and deeply mysterious But I suspect we will have little difficulty in understanding each other on the simpler aspects of astronomy, physics, chemistry and perhaps mathematics 4.5 stars The writing here warrants five stars At 40 years and counting and the fact the book could have been longer, this islike a 4 star book to me Cosmos and Pale Blue Dot still remain my favorite Sagan books and are beautiful works Sagan has long since passed away but I greatly miss his insights and his non righteous quest for the truth It really shines through in virtually all of his writing Highly recommended