How Brains Think: Evolving Intelligences, Then and Now

This book is a short survey of brain and mind. It isnt exhaustive, nor is it penetrating; Calvin touches all the important points and moves on. It's a good place to begin study about brain and mind. He writes well and isnt difficult to understand. The chapter about climate and global warming surprised me, and it increased my enjoyment of the book because Calvin treats the subject fairly without the hysteria and hype. I want the bottomline, not the hype of rentseekers looking to milk the government with junk science. If the Greenland icepack melts, the Gulfstream stops warming Europe, and hell is unleashed. But it happens anyway because of astronomical interactions no one can control. It's simply a question of which event occurs first. So! What's this book about? What's the message? Intelligence is evolution's response to chaos and tumult. When life is good for too long evolution whittles your brain to a size that meets your needs. Whales and cattle and horses arent great thinkers. They have plenty of food and stable habitats, and dont require smart brains. People are smarter than dogs but function at the level of the average pup. A dozen tricks and 50 words generally do our necessary work, and most of our tricks are hardwired at the factory, like dogs. The average person needs intelligence to remember to shower or save some money for the rent. Dogs dont fret about baths or where theyre gonna sleep, and few humans do any serious thinking. Our American lives are very stable. Mother Nature doesnt like stability. Consequently stability sets you up for extinction.

Calvin offers an evolutionary description of the development of human intelligence. He's very careful to avoid using "consciousness" since Dennett, Humphreys, Pinker and others have firmly employed that term. Calvin cites Piaget's "intelligence is what you use when you don't know what to do next" as a foundation thesis. From this he compares human mental talents with those of other animals, mostly primates, to demonstrate evolutionary roots for our intelligence. Behaviour issues common to everyday life become visible evidence for what is going on in our brains. Calvin manages to take his analysis into the physical processes that occur as we decide on our actions. It's a well written and "down to earth" explanation of many questions we have on what intelligence is and how we use it. Piaget's comment reflects the growing knowledge of brain processes. Much of the brain's time is spent collecting, storing, retrieving and applying information. This means that both "unconscious" events and our expressions and actions only come about after numerous and complicated signal processing has already occurred. Calvin describes in both text and graphics how neurons are constructed, convey data, and interact within the brain. Clearly, nothing is instantaneous and many elements are competing for dominance during every moment awake. Clear, too, is the notion that while other primates have many talents to deal with their surroundings, none possess the powers evolution gave humans. What drives these powerful mental abilities? He rebuffs the idea of the "quantum brain". It's too deep in the brain's structure - "in the subbasement of physics". That's too far removed from areas of vision, speech, and memory. There are certainly quantum events going on with all that chemical and electrical activity inside your skull, but Calvin sees these forces as far to deep to have direct impact on mental processes. Calvin is more concerned with the human level of analysis. One proposal he adopts wholeheartedly, but without attribution, is Daniel Dennett's concept of the "multiple drafts model" of thinking and expression. Calvin, to his credit, outstrips even Dennett's abilities of description in depicting this process. He shows, for example, how the brain's memory storage facility considers many images before it resolves that the round thing flying past is a tennis ball. It's an exquisite example, and you perceive clearly how many other daily occurrences are resolved in a similar manner. The accumulation of evidence about our evolutionary roots, the environmental changes forced on us and the rise of language and use of syntax are all contained within a device Calvin labels the "Darwin Machine." The Machine has six "essentials" which cover topics like replication, mutation and success in adaptation. He demonstrates how the "essentials" provide a mechanism for complexity from simplicity. Where some creatures modified things like limbs, teeth or hair, it was ou

This book is an attempt to "pull together all of the essentials.....of a darwinian process" and "describe a specific neural mechanism that could implement such a process in primate neocortex." Calvin is an advocate of the idea that brain-based darwinian processes are what provides brains with what we call "consciousness" and "intelligence". The first six chapters do the pulling together and chapter seven presents the proposed mechanism. Chapter 8 explores implications of darwinian brain processes for artificial intelligence.As we plod along towards Alan Turing's dream of constructing intelligent machines, there are a few road-blocks we need to get around. Calvin mentions that any explanation of biological intelligence ought to have implications for artificial intelligence. He admits that, "the ad-hoc schemes of AI might also produce intelligent robots", but he clearly likes the idea that the most efficient path to intelligent man-made devices that can duplicate human mental abilities (what Calvin quaintly calls a "workalike") is to learn the essentials of how biological brains work and then apply those principles to the problem of making a workalike. One road-block is the fact that so many AI researchers ignore the task of reverse engineering the human brain or, at best, they assume that what was known about brains in the 1940's is enough. Unfortunately, I doubt that Calvin's hop-skip-and-jump over this issue will move any AI researchers away from their "ad-hoc schemes". Even AI researchers who like the idea of evolutionary processes pay little attention to the idea of adapting the physiological mechanisms of biological brains to evolutionary computing.A second road-block is the distinction that is usually made between hardware and software. Turing was among the first to recognize how to use electronic devices to implement the power and beauty of this distinction, and most AI researchers remain devoted to hardware-software duality. Unfortunately, biological brains were not designed by an electrical engineer. It thus becomes a danger that biologists will mistakenly attempt to make sense of biological brains by looking at brain processes through the distorting lenses of hardware-software duality. I think that Calvin gets caught in this trap of dualism and it deflects him from paying close enough attention to the details of how biological brains really work.Calvin's dualistic thinking starts with the harmless division of brain processes into two types, those that depend on "cerebral ruts" (hardware) and those that dance more freely through the brain and so are able to function like "software".....Calvin usually calls these "firing patterns". The dangerous step comes when Calvin suggests that the pattern of action potentials in any particular neocortical minicolumn can be replicated and spread through the cortex like a piece of software code and be "played" on the millions of other minicolumns in the same way you can play a million copies of a CD on

In Chapter 1 of How Brains Think, William H. Calvin recalls Piaget "who used to say that intelligence is what you use when you don't know what to do." Throughout the balance of this immensely readable as well as informative book, Calvin attempts to explain what is so difficult to understand: the interaction between the brain and the mind, and, the interaction of the mind with the physical world in which it exists. "The big issue for understanding intelligence isn't who has more but what intelligence is, when it's needed, and how it operates. Some of what intelligence encompasses are cleverness, foresight,, speed, creativity, and how many things you can juggle at once." Although Calvin is an eminent theoretical neurophysiologist, How Brains Think is not a textbook in which he explains in mind-numbing detail the brain, the mind, and their interaction. Calvin has written How Brains Think for the reasonably intelligent non-scientist. As Calvin concludes How Brains Think, he observes: It behooves us to be a considerate creator [of superintelligent machines], wise to the world and its fragile nature, sensitive to the need for stable footings that will prevent backsliding -- and keep the house of cards we call civilization from collapsing.Near the end of his book, Calvin quotes from Lewis Thomas' masterpiece The Medusa and the Snail: "We need science, more and better science, not for its technology, not for its leisure, not even for health and longevity, but for the hope of wisdom which our kind of culture must acquire for its survival." Albert Borgmann, Eric Drexler, Thomas Friedman, and Joel Mokyr (among others) rise to their feet to join William Calvin in applauding Thomas' comments. If intelligence is "what you use when you don't know what to do", then "more and better science" must help to provide the "wisdom" of knowing precisely what to do...and what not to do. That's how brains should think. And will, Calvin believes, but if only we have courage and determination sufficient to the task.Calvin helps an interested layman (at least this one) to understand a rather complicated body of phenomena...doing so with style, grace, and wit. This is a book I re-read at least twice a year. Are Calvin's ideas that stimulating? Yes.

I found this book to be a great introduction to the study of mind and brain. It was the first time I read anything by Calvin so I look forward to reading his other writings. I highly recommend it.