Three reasons to read "The Symbolic Species". 1) Deacon describes how neuroscience is finally producing results that deal with the issue of how brains make human language possible. 2) Deacon presents a theory of brain/language co-evolution that stresses the importance of behavioral innovations that alter the human environment leading to subsequent genetic adaptation. 3) Deacon explores ways fold enterprise depends on the neuroscience results discussed in Part Two of "The Symbolic Species". For example, Figure 7.8 draws our attention to the idea that prefrontal cortex is disproportionately large in the human brain. Deacon suggests that changes in the relative sizes of brain regions during human evolution is a mechanism for adaptations that allow humans to better perform language tasks. Figure 8.3 pictorially illustrates an evolutionary trend in anatomical connections towards more direct cerebral cortex control over the motor neurons that are involved in vocalizations. These examples illustrate the fact that Deacon's theory of brain/language co-evolution is heavily dependent on comparative studies of brain anatomy. Deacon tries to convince us that the major anatomical changes during human brain evolution are the precise types of changes in an ape brain that would facilitate human language behavior. According to Deacon's theory, early humans started using language as a social innovation and then the human brain changed so as to make it easier to use human language. The fact that human social interactions are a huge part of the human environment guarantees that there has to be some truth in Deacon's theory, but is it just part of a larger story?

A specific issue that Deacon touches on is the fact that non-human apes are able to learn the basics of human language simply human apes learn the basics of language rapidly and then stop developing more sophisticated language behavior just at the developmental stage where human children are taking off with a huge vocabulary and increasingly complex syntax? The best that Deacon's theory can suggest is that humans, unlike chimps, have had 2 million years of language use and subsequent brain evolution in response to selective pressure for larger brain regions that aid in symbolic thought. I agree that it would be astounding if certain brain regions such as the adult human prefrontal cortex is not more useful for human language tasks than is the chimp prefrontal cortex, but is this really the most important thing we need to know about the relationship between brains and language?

Is there another way of looking at the difference between human and chimp brains? One that might better inform us about the functional differences between human and chimp brains that give humans superior language skills? Deacon mentions an alternative in Chapter 6, "...the rate of human brain maturation...is prolonged compared to other primates..." In fact, most human brain growth happens after birth while most chimp brain growth happens before birth. What does this have to do with language behavior?

Perhaps everything. Why DO humans have big brains? Even though Deacon correctly points out the fact that, in the case of brains, bigger does not mean better, his whole theory ends up depending on the idea that competent brain, the mechanism of "parcellation", which he claims can mechanistically explain data such as those given in Figure 8.3. Can parcellation really do all the explanatory work that his theory demands or is there a need for additional mechanisms?

Why DO humans have big brains? What if big human brains are just a side effect of some other more important aspect of brain physiology? What if larger human brain size is just a side effect of evolutionary selection for prolonged synaptic plasticity during human childhood? Maybe if we could alter a few genes in bonobos so as to prolong postnatal brain growth in certain bonobo brain regions like the anterior cingulate cortex, just maybe we would give bonobos a longer window for developing sophisticated language skills.

There is a whole tradition within neuroscience that started with behavioral studies of associative learning and led to studies of the cellular and molecular mechanisms of learning and memory. This branch of neuroscience research is almost completely ignored evolution into a corner.

So my advice is that people who are interested in language should read Deacon's book, but recognize the limitations of his perspective. In the next few decades the rest of the story of how brains make human language behavior possible will come rolling in. Deacon has provided us with a working model of how to apply this hard-won knowledge of the brain to our understanding of human language, but Deacon's is just an early pass at this kind of empirically-anchored theoretical neurolingustics. Much more is yet to come. Even scientists should heed Wittgenstein's warning not to be too quick to formulate grand theories of language while so much data remains to be collected.

Reading only one or two pages into this book already makes it clear that this is a work by an exceptionally well informed and disciplined writer; and reading to the end does not disappoint at any time. This is a tightly argued serious scientific thesis by a professor of biological anthropology with an encyclopedic knowledge of linguistics, neurophysiology, neuroanatomy and human evolution. It is an original work in which Deacon sets out his arguments and marshals the evidence for a comprehensive theory in a methodical and structured way. It is not for the faint hearted, and reading it demands careful attention to the tightly written dense structured prose; it is not repetitive and the logical structure of the arguments is architectural, so that careful reading and a good memory are essential. Useful diagrammatic illustrations help to make some of the concepts easier to grasp. The effort is worth every moment. Deacon's conclusions have consequences for philosophy and theory of mind no less than for the central area of linguistics and the evolution of human intelligence. This book has done more to shape and to consolidate my knowledge of who we as a "symbolic species" are than any other I have read in this decade. Strongly recommended.

I edited THE SYMBOLIC SPECIES when I was employed atW. W. Norton, and no book I worked on in my fourteen years at Nortonever received so many enthusiastic comments and reviews from leading scholars in related fields. Prospective readers may like to know that cutting edge thinkers and researchers such as Merlin Donald, author of ORIGINS OF THE MODERN MIND, consider Terry Deacon's revolutionary exploration of human origins and consciousness to be "the best book yet written on the evolution of language" and "theoretical dynamamite planted deep under the walls of the neo-Chomskian fortress." Edward Manier, professor of philosophy at University of Notre Dame, says the book "should transform the foundations of the human sciences" and calls Deacon the "best neurophilosopher on the planet." Here are these and other leading scholars' advance reviews of THE SYMBOLIC SPECIES, along with excerpts from Booklist and the starred review in Library Journal.

"An extremely sophisticated analysis of the relationship between language and the brain. Deacon provides a compelling picture of how language evolved to fit the ape brain. He also explains why and how different languages may utilize different parts of the brain to carry out the same linguistic function." -- Patricia Greenfield, professor of psychology, UCLA

"A masterpiece. This superb and innovative look at the evolution of language could only have been written - David Pilbeam, professor of anthropology, Harvard University

"This is an accessible yet erudite volume, witty and uncompromising. In my opinion it is the best book yet written on the evolution of language. Deacon has mounted a serious challenge to the neo-Chomskians. He has constructed a credible theory of language evolution that places grammar in a secondary role. The evolutionary action, says Deacon, is in the lexicon, and in the social nature of symbolic invention, rather than in grammar. Grammars emerge from the demands of the linguistic environment itself. Children learn grammar easily and fast, not because it is programmed into their genes, but because the language environment has its own built-in heuristic. This is theoretical dynamite, planted deep under the walls of the neo-Chomskian fortress.

"Deacon also has a great deal to say about how the human brain has adapted itself to deal with the challenge of symbolic reference, and especially on the complex relationships between brain growth, cognitive development, and social evolution. This is essential reading for anyone interested in what makes us human." -- Merlin Donald, professor of psychology, Queens University (Ontario and author of Origins of the Modern Mind

"If you have only one book to read on the evolution and function of the human brain, this is the one I would recommend." -- Jerome Kagan, Daniel and Amy Starch Professor of Psychology, Harvard University

"Terry Deacon's The Symbolic Species should transform the foundations of the human sciences.

"The book relocates the most significant puzzles of 'neurophilosophy$ in the context of the latest evolutionary models. These track the impact of a shift in social structures caused indicated neurobiologicalreference: the yawning chasm on the rocky evolutionary-neurobiological road from icons and indices to symbols. No other account of the 'language instinct' covers these issues.

"Deacon offers fresh insight into philosophic controversies over eliminative materialism, 'the Chinese Room' and 'the Cartesian Theater,' and 'kinds of minds.' His discussion of levels of consciousness is remarkable for its lack of sectarian cant. His evolutionary naturalism escapes the old labels of reductionism, instrumentalism, and physicalism.

"Deacon combines the precision of a neurosurgeon with the rigor of a philosopher. He's my candidate for best neurophilosopher on the planet. His impressive command of comparative neuroscience, psycholinguistics, evolutionary theory and related disciplines makes this book indispensable for my courses in the philosophy of biology, philosophy of cognitive neuroscience, and philosophy, psychology and psychiatry. The Symbolic Species is not another grandiose lyric about the global properties of the brain. When this author finds 'nascent heart and mind' where most fear clockwork, he doesn't persuade his readers to believe; he shows them where to look." -- A. Edward Manier, professor of philosophy and of the history and philosophy of science, University of Notre Dame

"Terrence Deacon's book provides a remarkable and even-handed synthesis of knowledge obtained from a wide range of disciplines. THE SYMBOLIC SPECIES helps us understand why we are so remarkably different from other species in terms of learning the kinds of language systems that we do--and yet not all that different from the apes in terms of basic organization and function of our primate brain. THE SYMBOLIC SPECIES is written in a highly engaging style that permits us seemingly to hear the author's voice and to sense the spirit with which he so avidly pursued answers to questions of high interest to us all. THE SYMBOLIC SPECIES is an outstanding product of a gifted scholar. The book will be of great value to the curious lay reader as well as, of course, both to undergraduate and graduate courses." -- Duane M. Rumbaugh, professor of psychology, Georgia State University

"Both fascinating and accessible. In Deacon's exploration of human consciousness, the realms of neuroscience and evolutionary biology, among others, are within reach as Deacon >ponders how language came about, how the brains of Homo sapiens function, and why they are wired in ways that allow us to communicate - Booklist, July 1997

"Deacon challenges many of the ideas of Noam Chomsky and, more recently, Steven Pinker . . . [and] blends a knowledge of neurobiology, anthropology, linguistics, and philosophy into an original, well-argued, compelling theory of language development." -- Library Journal (starred review)