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Hardcover | $47.00 Short | £32.95 | ISBN: 9780262025485 | 492 pp. | 7 x 9 in | 34 illus.| December 2003
Paperback | $35.00 Short | £24.95 | ISBN: 9780262524575 | 492 pp. | 7 x 9 in | 34 illus.| January 2006
Ebook | $24.95 Short | ISBN: 9780262310567 | 492 pp. | 7 x 9 in | 34 illus.| January 2006

What Is Thought?


In What Is Thought? Eric Baum proposes a computational explanation of thought. Just as Erwin Schrodinger in his classic 1944 work What Is Life? argued ten years before the discovery of DNA that life must be explainable at a fundamental level by physics and chemistry, Baum contends that the present-day inability of computer science to explain thought and meaning is no reason to doubt there can be such an explanation. Baum argues that the complexity of mind is the outcome of evolution, which has built thought processes that act unlike the standard algorithms of computer science and that to understand the mind we need to understand these thought processes and the evolutionary process that produced them in computational terms.

Baum proposes that underlying mind is a complex but compact program that corresponds to the underlying structure of the world. He argues further that the mind is essentially programmed by DNA. We learn more rapidly than computer scientists have so far been able to explain because the DNA code has programmed the mind to deal only with meaningful possibilities. Thus the mind understands by exploiting semantics, or meaning, for the purposes of computation; constraints are built in so that although there are myriad possibilities, only a few make sense. Evolution discovered corresponding subroutines or shortcuts to speed up its processes and to construct creatures whose survival depends on making the right choice quickly. Baum argues that the structure and nature of thought, meaning, sensation, and consciousness therefore arise naturally from the evolution of programs that exploit the compact structure of the world.

About the Author

Eric B. Baum has held positions at the University of California at Berkeley, Caltech, MIT, Princeton, and the NEC Research Institute. He is currently developing algorithms based on Machine Learning and Bayesian Reasoning to found a hedge fund.


"A book that is admirable as much for its candor as its ambition.... If What is Thought? can inspire a new generation of computer scientists to inquire anew about the nature of thought, it will be a valuable contribution indeed."—Gary Marcus, Science

"... [Should] engage general readers who wish to enjoy a clear, understandable description of many advanced principles of computer science."—Igor Aleksander, Nature


"There is no problem more important, or more daunting, than discovering the structure and processes behind human thought. What is Thought? is an important step towards finding the answer. A concise summary of the progress and pitfalls to date gives the reader the context necessary to appreciate Baum's important insights into the nature of cognition."—Nathan Myhrvold, Managing Director, Intellectual Ventures, and former Chief Technology Officer, Microsoft

"A major work. Berger offers an elegant examination of issues that have been in controversy for the last forty years and that have been and are being discussed by the best philosophers of language. But where others have tended to offer piecemeal solutions, Berger offers a unified account based on a small set of principles."—Gilbert Harman, Department of Philosophy, Princeton University

"Eric Baum's book is a remarkable achievement. He presents a novel thesis—that the mind is a program whose components are semantically meaningful modules—and explores it with a rich array of evidence drawn from a variety of fields. Baum's argument depends on much of the intellectual core of computer science, and as a result the book can also serve as a short course in computer science for non-specialists. To top it off, What is Thought? is beautifully written and will be at least as clear and accessible to the intelligent lay public as Scientific American."—David Waltz, Director, Center for Computational Learning Systems, Columbia University

"In his enjoyable and informative book The Evolution of Morality, Richard Joyce distinguishes between explaining how natural selection might explain socially useful behavior in animals and what more is needed to explain morality, with its thoughts about right or wrong, in human beings. Contrary to what others have said, Joyce argues plausibly that, to the extent that our moral concepts and opinions are the results of natural selection, there is no rational basis for these concepts and opinions."—Gilbert Harman, Department of Philosophy, Princeton University