Lingua Ex Machina: Reconciling Darwin and Chomsky With the Human Brain 0262032732, 9780262032735

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Reconciling Darwin and

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Chomsky

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William H. Calvin

Derek Bickerton

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Books by DEREK BICKERTON Lingua ex Machina Language and Human Behavior Language and Species Roots of Language

Books by WILLIAM H. CALVIN Lingua ex Machina The Cerebral Code How Brains Think Conversations with Neil’s Brain* How the Shaman Stole the Moon The Ascent of Mind The Cerebral Symphony The River That Flows Uphill The Throwing Madonna Inside the Brain* *with GEORGE A. OJEMANN

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WILLIAM H. CALVIN DEREK BICKERTON

A Bradford Book The MIT Press Cambridge, Massachusetts London, England

First MIT Press paperback edition, 2001 Copyright ©2000 by William H. Calvin and Derek Bickerton All rights reserved. Except for brief excerpts and personal photocopying of a single chapter, no part of this book may be reproduced in any form (including information storage and retrieval, photocopying, and recording) without permission from the publisher.

[email protected] http://faculty.washington.edu/wcalvin [email protected] Supplements and corrections can be found on the web page http://WilliamCalvin.com/LEM This book was designed, and set in Palatino, by William H. Calvin; it was printed and bound in the USA.

Library of Congress Cataloging-in-Publication Data Calvin, William H., 1939Lingua ex Machina: Reconciling Darwin and Chomsky with the human brain / William H. Calvin, Derek Bickerton. p. cm. “A Bradford book.” Includes bibliographical references and index. ISBN 0-262-03273-2 (hc. : alk. paper), 0-262-53198-4 (pb) 1. Neurolinguistics. 2. Brain–Evolution. 3. Chomsky, Noam. 4. Darwin, Charles, 1809-1882. I. Bickerton, Derek. II. Title. QP399.C35 2000 612.8'2–dc21 99-33464 CIP

 &RQWHQWV 1. The Villa Serbelloni

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2. What Are Words? (DB)

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3. Why Putting Words Together Isn’t Easy (DB)

27

4. Bigger than a Word, Smaller than a Sentence (DB)

41

5. Language in the Brain (WHC)

55

6. How Are Memories Stored?

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67

7. Hexagonal Mosaics and Darwin Machines (WHC)

75

8. A Common Code: The Brain”s “Esperanto” Problem (WHC)

93

9. Protolanguage Emerging (DB)

103

10. Reciprocal Altruism as the Predecessor of Argument Structure (DB)

123

11. Role Links for Words (DB)

135

12. The Word Tree as a Secondary Use of Throwing’s Segmented Movement Planner (WHC)

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13. Corticocortical Coherence Promotes a Many-Voiced Symphonic Sentence (WHC)

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14. The Pump and the Slingshot (WHC)

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15. Darwin and Chomsky Together at Last (DB)

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Acknowledgments

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Linguistics appendix (DB)

215

Glossary

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Notes

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About the Authors

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Index

285

Linguistics is arguably the most hotly contested property in the academic realm. It is soaked with the blood of poets, theologians, philosophers, philologists, psychologists, biologists, and neurologists, along with whatever blood can be got out of grammarians. –RUSS RYMER in The New Yorker, 1992

That the ultimate answer in a long-lasting controversy combines elements of the two opposing camps is typical in biology. Opponents are like the proverbial blind men touching different parts of an elephant. They have part of the truth, but they make erroneous extrapolations from these partial truths. The final answer is achieved by eliminating the errors and combining the valid portions of the various opposing theories. –ERNST MAYR, This is Biology, 1997



The Villa Serbelloni Bellagio, Italy

Derek, People at dinner last night kept asking me what Chomsky’s innate grammar is all about. Where is this language macromutation in the brain, and all that? Wrong question, of course, but it’s a sure sign they’ve gotten used to the amazing view of Lake Como from the terrace where we eat at the Villa Serbelloni, on a long table with several dozen interesting people. You’ll see when you arrive. If there’s a clear evening before I get back from Milan, remember to watch for the last of the sunset over the Dolomites. Provided, of course, the other “residents” give you a chance. Several confessed to reading up on our subject, in anticipation of our arrival for a month of writing about the brain and language. It forcefully reminded me that Chomsky’s innateness has been the intellectual spectator sport of the last four decades. I tried to explain to them that some gene-specified aspect was unsurprising to a biologist – that you and I hoped to flesh it out with appropriate anthropology and neuroscience in a way that

 Chomsky wasn’t particularly interested in doing, and to provide some evolutionary proposals that wouldn’t rely on macromutations and the like. I also tried to explain your notion of protolanguage put forth in Language and Species, with a good supply of words but with sentence length limited to only a few words by the lack of structural elements such as phrases and clauses. Protolanguage has no way of saying who did what to whom, not without an enormous effort. I emphasized that there was a large gulf between protolanguage and our full-fledged syntax without any obvious intermediate states, quite a jump from my pidgin Italian to being able to nest four verbs in saying, “I think I saw him leave to go home.” It’s going to be challenging for us to try and describe how the gulf was first bridged by evolutionary processes. I hope we can avoid the deus ex machina quality of some of the previous attempts to explain the origins of language ability, the ones that finally seize upon a slender, unsupported reed as the way out of the muddied morass – the equivalent of that “god machine” the ancient Greek playwrights wheeled in to solve thorny plot problems. Yet it is a language machine we’re searching for, one capable of those elaborate maneuvers seen in language with syntax (you don't have to think about it; indeed, you can't turn language recognition off), but conforming to some design constraints imposed by the neurobiology (what it’s possible to do with mere neural circuits) and the evolutionary history (up from apelike communication and mental powers in only five million years, each stage bootstrapping the next). But, in a broader view, language is just our best example of the whole range of higher intellectual functions. Our lingua ex machina probably needs to be able to handle creative shaping up of quality (for instance, figuring out what to do with the leftovers in the refrigerator), long-range planning, procedural games, and even

 music. Solve the structural basis for one, and you might solve them all. I think that the linguists’ conceit, that syntax is what thought is all about (and that without syntax, you couldn’t think with any depth or originality), reflects a useful strategy for brain researchers, simply because syntax provides a lot of useful constraints on theorizing. But other parts of higher intellectual function might be even more useful in that regard. Want to lay any bets that we would discover more about higher intellectual function via studying music in the brain? Yes, music seems likely to be a spare-time use of the neural machinery evolved for thought and language – but we might be able to separate the issues of vocabulary and structuring better in music, where you have structure without predication, as the Israeli musicologist Ruth Katz reminded me at dinner! What’s unmusical in any culture might tell us what the neurons can’t do. Intelligence (in our sense of versatility in dealing with novel situations) is a particularly intriguing part of the puzzle of higher intellectual functions. But as Ernst Mayr once said, most species are not intelligent, which suggests “that high intelligence is not at all favored by natural selection” – or that it’s very hard to achieve. So our look at bootstrapping syntax also needs to keep in mind this more general problem of finding indirect ways of achieving intelligence. What gives rise to syntax might also give intelligence a big boost. Evolution, after all, is full of sidesteps, such as those conversions of function that Darwin identified. Wheelchair considerations may be what “paid for” all of those curb cuts on every corner, but most of their subsequent use involves wheeled suitcases, baby carriages, grocery carts, skateboards, bicycles, and other uses that would never have paid for it. Some of the underpinnings of language may be secondary uses as well, so we need to watch for free “curb cuts” affecting syntax. See you soon.

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