Read Darwin's Dangerous Idea Online
Authors: Daniel C. Dennett
diversity of opinion about when in the last six million years or so our lineage acquired these traits, in what order, and why, but these disagreements are as arguments that fixed a maximal speed of mutation and selection and amenable to further research—no better and no worse off— than showed that there had not been enough time on Earth for the
whole
disagreements about whether the archaeopteryx flew, for instance. On the process to have occurred locally.
purely theoretical front, and casting the net much more widely, conditions for Chomsky's arguments, from the poverty of the stimulus and the speed of the evolution of communication systems in general have been deduced (e.g., language acquisition, are analogous; they purport to show that there must Krebs and Dawkins 1984, Zahavi 1987), and the implications are being have been
large
gifts of design in the infant if we are to explain the speedy explored in simulation models and empirical experiments.
development of the mature competence. And while we can take solace in We saw in chapter 7 some of the ingenious speculations and models that the supposition that we may someday be able to confirm the presence of have been directed at the problem about how life bootstrapped itself into these innate structures by direct examination of the nervous system (like finding fossils of our extraterrestrial ancestors), we will have to accept the existence, and there is a similar bounty of clever ideas about how language disheartening conclusion that a larger portion than we had hoped of
learn-must have got going. There is no question that the origin of language is
ing theory,
considered in its most general form as the attempt to explain theoretically a much easier problem than the origin of life; we have such a the transition from utter ignorance to knowledge, is not the province of rich catalogue of not-so-raw materials with which to build an answer. We psychology at all, but rather of evolutionary biology at its most speculative.
may never be able to confirm the details, but if so this will not be a mystery
[Dennett 1980.]
but
only a bit of irreparable ignorance. Some particularly abstemious scientists may be reluctant to devote time and attention to such far-flung To my surprise, Chomsky missed the point of my commentary. Whereas exercises in deductive speculation, but that does not appear to be Chom-he himself had offered reflections on what would make psychology "inter-390 LOSING OUR MINDS TO DARWIN
Chomsky Contra Darwin: Four Episodes
391
sky's position. His reservations are directed not to the likelihood of success occurred that jogged our ancestors abruptly to the right in Design Space, it but to the very point of the enterprise.
was still a gradual design development under the pressure of natural selection---unless it was indeed a miracle or a hopeful monster. In short, although It is perfectly safe to attribute this development [of innate language struc-Gould has heralded Chomsky's theory of universal grammar as a bulwark tures] to "natural selection", so long as we realize that there is no sub-against an adaptationist explanation of language, and Chomsky has in return stance to mis assertion, that it amounts to nothing more than a belief that endorsed Gould's antiadaptationism as an authoritative excuse for rejecting there is some naturalistic explanation for these phenomena. [Chomsky the obvious obligation to pursue an evolutionary explanation of the innate 1972, p. 97.]
establishment of universal grammar, these two authorities are supporting each other over an abyss.
In December 1989, the MIT psycholinguist Steven Pinker and his graduate There have long been signs, then, of Chomsky's agnosticism—or even student Paul Bloom presented a paper, "Natural Language and Natural antagonism—towards Darwinism, but many of us have found them hard to Selection," to the Cognitive Science Colloquium at MIT. Their paper, which interpret. To some, he appeared to be a "crypto-creationist," but that didn't has itself subsequently appeared as a target article in
Behavioral and Brain
seem very plausible, especially since he had the endorsement of Stephen Jay
Sciences,
laid down the gauntlet:
Gould. Remember the linguist Jay Keyser's appeal (on page 279) to Gould's term "spandrel" to describe how language came to be? Keyser probably got Many people have argued that the evolution of the human language faculty his terminology from his colleague Chomsky, who got it from Gould, who in cannot be explained by Darwinian natural selection. Chomsky and Gould return has avidly endorsed Chomsky's view that language didn't really evolve have suggested that language may have evolved as the by-product of se-but just rather suddenly arrived, an inexplicable gift, at best a byproduct of lection for other abilities or as a consequence of as-yet unknown laws of the enlargement of the human brain.
growth and form.... [W]e conclude that there is every reason to believe mat a specialization for grammar evolved by a conventional neo-Darwinian Yes, the brain got big by natural selection. But as a result of this size, and process. [Pinker and Bloom 1990, p. 707]
the neural density and connectivity thus imparted, human brains could perform an immense range of functions quite unrelated to the original
"In one sense," Pinker and Bloom said (p. 708), "our goal is incredibly reasons for increase in bulk. The brain did not get big so that we could read boring. All we argue is that language is no different from other complex or write or do arithmetic or chart the seasons—yet human culture, as we abilities such as echolocation and stereopsis, and that the only way to explain know it, depends upon skills of this kind.... [T]he universals of language the origin of such abilities is through the theory of natural selection." They are so different from anything else in nature, and so quirky in their struc-arrived at this "incredibly boring" conclusion by a patient evaluation of ture, that origin as a side consequence of the brain's enhanced capacity, various analyses of multifarious phenomena that show beyond a reasonable rather than as a simple advance in continuity from ancestral grunts and doubt—surprise, surprise—that the "language organ" must indeed have gestures, seems indicated. (This argument about language is by no means evolved many of its most interesting properties as adaptations, just as any original with me, though I ally myself fully with it; this line of reasoning neo-Darwinian would expect. The response from the audience at MIT was follows directly as the evolutionary reading for Noam Chomsky's theory of anything but boring, however. Chomsky and Gould had been scheduled to universal grammar.) [Gould 1989b, p. 14.]
reply, so there was a standing-room-only crowd.8 The level of hostility and ignorance about evolution that was unabashedly expressed by Gould stresses that the brain's growth may not have been due initially to selection for language (or even for heightened intelligence) and that human language may not have developed "as a simple advance in continuity from ancestral grunts," but it does not follow from these suppositions (which we 8. As it turned out, Chomsky was unable to attend, and his place was taken by his (and may grant him for the sake of argument) that the language organ is not an my) good friend Massimo Piatelli-Palmarini (who almost always agrees with Chomsky, adaptation. It is, let us grant, an exaptation, but exaptations are adaptations.
and seldom agrees with me!). Piatelli-Palmarini was die optimal understudy; he had Let the remarkable growth of the hominid brain be a "spandrel" in whatever cotaught a seminar on cognition and evolution with Gould at Harvard, and was die author sense Gould or Keyser wishes, and
still
the language organ will be as much of the article (1989) that had first rendered explicit the Gould-Chomsky position on the nonevolution of language. His article had been a major provocation and target of Pinker an adaptation as the bird's wing! No matter how suddenly the punctuation and Bloom's essay.
392 LOSING OUR MINDS TO DARWIN
Nice Tries
393
eminent cognitive scientists on that occasion shocked me. (In fact, it was of battle. (As we shall see, this is everybody's weakness; I regret that the reflecting on that meeting that persuaded me I could no longer put off writing siege mentality among sociobiologists has led them to overlook—at any rate, this book.) So far as I know, no transcript of that meeting exists (the neglect to correct—more than a few cases of egregiously bad reasoning by commentaries in
BBS
include some of the themes raised at the meeting), but members of their own team.)
you can recover something of the flavor by contemplating Pinker's list One of Darwin's most enthusiastic supporters was Herbert Spencer, coiner (personal communication) of the ten most amazing objections he and Bloom of the phrase "the survival of the fittest" and an important clarifier of some of have fielded since drafts of their paper began to circulate. Versions of most of Darwin's best ideas, but also the father of Social Darwinism, an odious them, if memory serves me, were expressed at the MIT meeting: misapplication of Darwinian thinking in defense of political doctrines that range from callous to heinous.9 Was Darwin responsible for Spencer's misuse (1) Color vision has no function; we could tell red from green apples of his views? Opinions differ on this. For my part, I excuse Darwin from the using intensity cues.
truly heroic task of chastising his champion in public, even though I regret (2) Language is not designed for communication at all: it's not like a that he wasn't more energetic in pursuing private acts of dissuasion or watch, it's like a Rube Goldberg device with a stick in the middle that correction. Both Gould and Chomsky have been vigorous proponents of the you can use as a sundial.
view that intellectuals
are
responsible for the applications
and likely
(3) Any argument that language is functional could be made with equal
misapplications
of their own work, so presumably they are at least plausibility and force when applied to writing in sand.
embarrassed to find themselves cited as the sources of all this nonsense, for (4) The structure of the cell is to be explained by physics, not evolution.
they themselves do not hold these views. (It is perhaps too much to expect (5) Having an eye calls for the same kind of explanation as having mass, their gratitude to me for doing their dirty work for them.) because just as the eye lets you see, mass prevents you from floating into space.
(6) Hasn't that stuff about insect wings refuted Darwin?
3. NICE TRIES
(7) Language can't be useful; it's led to war.
(8) Natural selection is irrelevant, because we now have chaos theory.
In studying the evolution of mind, we cannot guess to what extent there
(9) Language couldn't have evolved through selection pressure for com-are physically possible alternatives to, say, transformational generative munication, because we can ask people how they feel without really
grammar, for an organism meeting certain other physical conditions
wanting to know.
characteristic of humans. Conceivably, there are none
—
or very few
—
in
(10) Everyone agrees that natural selection plays some role in the origin of
which case talk about evolution of the language capacity is beside the
the mind but that it cannot explain every aspect—thus there is
point.
nothing more to say.
—NOAM CHOMSKY 1972, p. 98
Are Gould and Chomsky responsible for the bizarre convictions of some of their supporters? This question has no simple answer. More than half of the items on Pinker's list have a clear ancestry in claims that have been made by 9. Spencer's woolly style was the target of William James' mockery in the epigraph for part II (p. 147). Spencer (1870, p. 396) had offered the following definition: "Evolution Gould (numbers 2, 6, and 9 in particular) and Chomsky (numbers 4, 5, and 10
is an integration of matter and concomitant dissipation of motion; during which the in particular). Those who make these claims (including the others on the list) matter passes from an indefinite, incoherent homogeneity to a definite, coherent heter-typically present them on the authority of Gould and Chomsky (see, e.g., ogeneity; and during which the retained motion undergoes a parallel transformation."
Otero 1990). As Pinker and Bloom say (1990, p. 708), "Noam Chomsky, the The memeology of James' marvelous parody is worth recording. I got the quotation from world's greatest linguist, and Stephen Jay Gould, the world's best-known Garrett Hardin, who informs me that he got it from Sills and Merton (1991, p. 104). They in turn cite James'
Lecture Notes 1880-1897
as their source, but Hardin has tracked evolutionary theorist, have repeatedly suggested that language may not be the down some further details. P. G. Tait (1880, p. 80 ) gives credit to a mathematician named product of natural selection." Moreover—two important dogs that haven't Kirkman for his "exquisite translation" of Spencer, of which James' version—presumably barked—I have yet to witness either Gould or Chomsky attempting to correct borrowed from Tait—is a mutation. Kirkman's (presumably ) original version: "Evolution these howlers when they arise in the heat
is a change from a nohowish, untalkaboutable all-alikeness, to a somehowish and in-general-talkaboutable, not-all-alikeness, by continuous somethingelsifications and sticktogetherations."
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Nice Tries
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To make progress in understanding all this, we probably need to begin
complexities to be found in organisms. Gould and Lewontin's ( 1979) brief
with simplified (oversimplified?) models and ignore the critics' tirade
alliance with "intrinsic"
Baupläne
that account for all but the minor trim-that the real world is more complex. The real world is always
more
mings of organism design is yet another.
complex, which has the advantage that we shan't run out of work.
Chomsky's suggestion that it is physics, not biology (or engineering), that
—JOHN BALL 1984, p. 159