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Title: Linguistics and Brain Science
Author: Noam Chomsky
Date: 2000
Language: en
Topics: language, science, Psychology
Source: Retrieved on 19th June 2021 from https://www.chomsky.info/articles/2000----.pdf
Notes: Published in A. Marantz, Y. Miyashita and W. O’Neil (eds.) Image, Language and Brain. pp. 13–28

Noam Chomsky

Linguistics and Brain Science

In the past half century, there has been intensive and often highly

productive inquiry into the brain, behavior, and cognitive faculties of

many organisms. The goal that has aroused the most enthusiasm is also

likely to be the most remote, probably by orders of magnitude: an

understanding of the human brain and human higher mental faculties,

their nature, and the ways they enter into action and interaction.

From the outset, there has been no shortage of optimistic forecasts,

even declarations by distinguished researchers that the mind-body

problem has been solved by advances in computation, or that everything

is essentially understood apart from the “hard problem” of

consciousness. Such conclusions surely do not withstand analysis. To an

objective outside observer — say, a scientist from Mars — the optimism

too might seem rather strange, since there is also no shortage of much

simpler problems that are poorly understood, or not at all.

Despite much important progress in many areas, and justified excitement

about the prospects opened by newer technologies, I think that a degree

of skepticism is warranted, and that it is wise to be cautious in

assessing what we know and what we might realistically hope to learn.

The optimism of the early postwar period had many sources, some of them

a matter of social history, I believe. But it also had roots in the

sciences, in particular, in successful integration of parts of biology

within the core natural sciences. That suggested to many people that

science might be approaching a kind of “last frontier,” the mind and the

brain, which should fall within our intellectual grasp in due course, as

was soon to happen with DNA.

Quite commonly, these investigations have adopted the thesis that

“Things mental, indeed minds, are emergent properties of brains,” while

recognizing that “these emergences are not regarded as irreducible but

are produced by principles that control the interactions between lower

level events — principles we do not yet understand.” The last phrase

reflects the optimism that has been a persistent theme throughout this

period, rightly or wrongly.

I am quoting a distinguished neuroscientist, Vernon Mountcastle of the

Johns Hopkins University Institute of Mind/Brain. Mountcastle is

introducing a volume of essays published by the American Academy of Arts

and Sciences, with contributions by leading researchers, who review the

achievements of the past half century in understanding the brain and its

functions (“The Brain” 1998). The thesis on emergence is widely accepted

in the field, often considered a distinctive contribution of the current

era. In the last few years, the thesis has repeatedly been presented as

an “astonishing hypothesis,” “the bold assertion that mental phenomena

are entirely natural and caused by the neurophysiological activities of

the brain” and “that capacities of the human mind are in fact capacities

of the human brain.” The thesis has also been offered as a “radical new

idea” in the philosophy of mind that may at last put to rest Cartesian

dualism, some believe, while others express doubt that the apparent

chasm between body and mind can really be bridged.

Within the brain and cognitive sciences, many would endorse the position

expressed by Harvard evolutionary biologist E. O. Wilson in the same

American Academy issue on the brain: “Researchers now speak confidently

of a coming solution to the brain-mind problem,” presumably along the

lines of Mountcastle’s thesis on emergence. One contributor, the eminent

neurobiologist Semir Zeki, suggests that the brain sciences can even

confidently anticipate addressing the creative arts, thus incorporating

the outer limits of human achievement within the neurosciences. He also

observes that the ability to recognize “a continuous vertical line is a

mystery that neurology has not yet solved”; perhaps the word yet is a

bit more realistic here.

As far as I am aware, the neural basis for the remarkable behavior of

bees also remains a mystery. This behavior includes what appear to be

impressive cognitive feats and also some of the few known analogues to

distinctive properties of human language, notably the regular reliance

on “displaced reference” — communication about objects not in the

sensory field (Griffin 1994). The prospects for vastly more complex

organisms seem considerably more remote.

Whatever one may speculate about current prospects, it is worth bearing

in mind that the leading thesis about minds as emergent properties of

brains is far from novel. It revives eighteenth-century proposals put

forth for compelling reasons, by, among others, the famous English

scientist Joseph Priestley, and before him, the French physician Julien

Offray de la Mettrie. As Priestley formulated the thesis, “The powers of

sensation or perception and thought” are properties of “a certain

organized system of matter.” Properties “termed mental are the result

[of the] organical structure” of the brain and “the human nervous

system” generally.

In other words, “Things mental, indeed minds, are emergent properties of

brains” (Mountcastle). Priestley of course could not say how this

emergence takes place, and we are not much better off after 200 years.

The reasons for the eighteenth-century conclusions about emergence were

indeed compelling. I think the brain and cognitive sciences can learn

some useful lessons from the rise of the emergence thesis 200 years ago,

and from the ways the sciences have developed since, right up to

mid-twentieth century, when the assimilation of parts of biology to

chemistry took place. The debates of the early part of this century

about atoms, molecules, chemical structures and reactions, and related

matters are strikingly similar to current controversies about mind and

brain. I would like to digress for a moment on these topics —

instructive and pertinent ones, I think.

The reasoning that led to the eighteenth-century emergence thesis was

straightforward. The modern scientific revolution was inspired by the

“mechanical philosophy,” the idea that the world is a great machine that

could in principle be constructed by a master artisan and that is

therefore intelligible to us, in a very direct sense. The world is a

complex version of the clocks and other intricate automata that

fascinated the seventeenth and eighteenth centuries, much as computers

have provided a stimulus to thought and imagination in recent years —

the change of artifacts has limited consequences for the basic issues,

as Alan Turing demonstrated sixty years ago.

In that context, Descartes had been able to formulate a relatively clear

mind-body problem: it arose because he observed phenomena that, he

plausibly argued, could not be accounted for in terms of automata. He

was proven wrong, for reasons he could never have guessed: nothing can

be accounted for within the mechanical philosophy, even the simplest

terrestrial and planetary motion. Newton established, to his great

dismay, that “a purely materialistic or mechanistic physics ... is

impossible” (Koyré 1957:210).

Newton was bitterly criticized by leading scientists of his day for

reverting to the mysticism from which we were at last to be liberated by

the scientific revolution. He was condemned for reintroducing “occult

qualities” that are no different from the mysterious “sympathies” and

“antipathies” of the neoscholastic Aristotelian physicists, which were

much ridiculed. Newton agreed. He regarded his discoveries as an utter

“absurdity,” and for the rest of his life sought some way around them:

he kept searching for a “certain most subtle spirit which pervades and

lies hid in all gross bodies,” and would account for motion,

interaction, electrical attraction and repulsion, properties of light,

sensation, and the ways in which “members of animal bodies move at the

command of the will” — comparable mysteries, he felt.

Similar efforts continued for centuries, but always in vain. The

absurdity was real, and simply had to be accepted. In a sense it was

overcome in this century, but only by introducing what Newton and his

contemporaries would have regarded as even greater absurdities. We are

left with the “admission into the body of science of incomprehensible

and inexplicable ‘facts’ imposed upon us by empiricism” (Koyré

1957:272).

Well before Priestley, David Hume wrote that “Newton seemed to draw off

the veil from some of the mysteries of nature,” but “he shewed at the

same time the imperfections of the mechanical philosophy; and thereby

restored [Nature’s] ultimate secrets to that obscurity, in which they

ever did and ever will remain” (Hume [1778] 1983:542). The world is

simply not comprehensible to human intelligence, at least in the ways

that early modern science had hoped and expected. In his classic study

of the history of materialism, Friedrich Lange observes that their

expectations and goals were abandoned, and we gradually “accustomed

ourselves to the abstract notion of forces, or rather to a notion

hovering in a mystic obscurity between abstraction and concrete

comprehension.” Lange describes this as a “turning-point” in the history

of materialism that removes the surviving remnants of the doctrine far

from those of the “genuine Materialists” of the seventeenth century, and

deprives them of much significance (Lange 1925:308).

The turning point also led gradually to a much weaker concept of

intelligibility than the one that inspired the modern scientific

revolution: intelligibility of theories, not of the world — a

considerable difference, which may well bring into operation different

faculties of mind, a topic some day for cognitive science, perhaps.

A few years after writing the introduction to the English translation of

Lange’s history, Bertrand Russell illustrated the distinction with an

example reinvented recently and now a centerpiece of debates over

consciousness. Russell pointed out that “a man who can see knows things

which a blind man cannot know; but a blind man can know the whole of

physics,” so “the knowledge which other men have and he has not is not

part of physics” (Russell 1929:389). Russell is referring to the

“qualitative knowledge which we possess concerning mental events,” which

might not simply be a matter of conscious awareness, as the phenomenon

of blindsight suggests. Some leading animal researchers hold that

something similar may be true of bees (Griffin 1994). Russell’s own

conclusion is that the natural sciences seek “to discover the causal

skeleton of the world,” and can aim no higher than that. “Physics

studies percepts only in their cognitive aspect; their other aspects lie

outside its purview” (Russell 1929:391±392).

These issues are now very much alive, but let us put them aside and

return to the intellectual crisis of eighteenth-century science.

One consequence was that the concept of “body” disappeared. There is

just the world, with its many aspects: mechanical, chemical,

electromagnetic, optical, mental — aspects that we may hope to unify

somehow, but how no one knows. We can speak of “the physical world,” if

we like, but for emphasis, without implying that there is some other

world — rather the way we speak of the “real truth,” without meaning

that there is some other kind of truth. The world has occult properties,

which we try to comprehend as best we can, with our highly specific

forms of intelligence, which may leave much of nature a mystery, at

least if we ourselves are part of the biological world, not angels.

There is no longer a “mind-body problem,” because there is no useful

notion of “body,” of the “material” or “physical” world. The terms

simply indicate what is more or less understood and assimilable in some

manner to core physics, whatever that turns out to be. For individual

psychology, the emergence hypothesis of contemporary neuroscience

becomes a truism: there is no coherent alternative, with the abandonment

of materialism in any significant sense of the concept.

Of course, that leaves all empirical problems unsolved, including the

question of how bees find a flower after watching the “waggle dance,”

and how they know not even to leave the hive if the directions lead to

the middle of a lake, it has been reported (Gould 1990). Also included

are questions about the relation between the principles of human

language and properties of cells. Included as well are the much more

far-reaching problems that troubled Descartes and Newton about the

“commands of the will,” including the normal use of language —

innovative, appropriate, and coherent, but apparently uncaused. It is

useful to remember that these problems underlie Descartes’s

two-substance theory, which was put to rest by Newton, who showed that

one of the two substances does not exist: namely body.

How do we address the real problems? I know of no better advice than the

recommendations of the eighteenth-century English chemist Joseph Black:

“Chemical affinity must be accepted as a first principle, which we

cannot explain any more than Newton could explain gravitation, and let

us defer accounting for the laws of affinity until we have established

such a body of doctrine as Newton has established concerning the laws of

gravitation” (Black, quoted in Schofeld 1970:226). That is pretty much

what happened. Chemistry proceeded to establish a rich body of doctrine,

“its triumphs ... built on no reductionist foundation but rather

achieved in isolation from the newly emerging science of physics”

(Thackray 1970). That continued until recently. What was finally

achieved by Linus Pauling sixty years ago was unification, not

reduction. Russell’s observation in 1929 that chemical laws “cannot at

present be reduced to physical laws” turns out to have been misleading,

in an important way (Russell 1929). Physics had to undergo fundamental

changes, mainly in the 1920s, in order to be unified with basic

chemistry, departing even more radically from commonsense notions of

“the physical.” Physics had to “free itself” from “intuitive pictures”

and give up the hope of “visualizing the world,” as Heisenberg put it

(quoted in Holton 1996:191), another long leap away from intelligibility

in the sense of the scientific revolution of the seventeenth century,

which brought about the “first cognitive revolution” as well.

The unification of biology and chemistry a few years later can be

misleading. That was genuine reduction, but to a newly created physical

chemistry; some of the same people were involved, notably Pauling. True

reduction is not so common in the history of science, and need not be

assumed automatically to be a model for what will happen in the future.

Prior to the unification of chemistry and physics in the 1930s, it was

commonly argued by distinguished scientists, including Nobel Prize

winners in chemistry, that chemistry is just a calculating device, a way

to organize results about chemical reactions, sometimes to predict them.

Chemistry is not about anything real. The reason was that no one knew

how to reduce it to physics. That failure was later understood:

reduction was impossible, until physics underwent a radical revolution.

It is now clear — or should be clear — that the debates about the

reality of chemistry were based on fundamental misunderstanding.

Chemistry was “real” and “about the world” in the only sense of these

concepts that we have: it was part of the best conception of how the

world works that human intelligence had been able to contrive. It is

impossible to do better than that.

The debates about chemistry a few years ago are in many ways echoed in

the philosophy of mind and the cognitive sciences today — and

theoretical chemistry, of course, is hard science, merging

indistinguishably with core physics. It is not at the periphery of

scientific understanding, like the brain and cognitive sciences, which

are trying to study systems vastly more complex. I think these recent

debates about chemistry, and their surprising outcome, may be

instructive for the brain and cognitive sciences. We should follow

Joseph Black’s good advice and try to construct “bodies of doctrine” in

whatever terms we can, unshackled by commonsense intuitions about how

the world must be — we know that it is not that way — and untroubled by

the fact that we may have to “defer accounting for the principles” in

terms of general scientific understanding. This understanding may turn

out to be inadequate to the task of unification, as has regularly been

the case for 300 years. A good deal of discussion of these topics seems

to me misguided, perhaps seriously so, for reasons such as these.

Other similarities are worth remembering. The “triumphs of chemistry”

offered useful guidelines for the eventual reconstruction of physics:

they provided conditions that core physics would have to meet, in some

manner or other. In a similar way, discoveries about bee communication

provide conditions that have to be met by some account in terms of

cells. In both cases, it is a two-way street: the discoveries of physics

constrain possible chemical models, as those of basic biology should

constrain models of insect behavior.

There are familiar analogues in the brain and cognitive sciences: the

issue of computational, algorithmic, and implementation theories

emphasized particularly by David Marr, for example. Or Eric Kandel’s

work on learning in marine snails, seeking “to translate into neuronal

terms ideas that have been proposed at an abstract level by experimental

psychologists,” and thus to show how cognitive psychology and

neurobiology “may begin to converge to yield a new perspective in the

study of learning” (Hawkins and Kandel 1984:380, 376). Very reasonable,

though the actual course of the sciences should alert us to the

possibility that the convergence may not take place because something is

missing — where, we cannot know until we find out.

Questions of this kind arise at once in the study of language and the

brain. By language I mean “human language,” and understand each

particular language to be a state of a subcomponent of the brain

specifically dedicated to language — as a system that is; its elements

may have other functions. It seems clear that these curious brain states

have computational properties: a language is a system of discrete

infinity, a procedure that enumerates an infinite class of expressions,

each of them a structured complex of properties of sound and meaning.

The recursive procedure is somehow implemented at the cellular level,

how no one knows. That is not surprising; the answers are unknown for

far simpler cases. Randy Gallistel observes that “we clearly do not

understand how the nervous system computes,” even “how it carries out

the small set of arithmetic and logical operations that are fundamental

to any computation.” His more general view is that in all animals,

learning is based on specialized mechanisms, “instincts to learn” in

specific ways. These “learning mechanisms” can be regarded as “organs

within the brain [that] are neural circuits whose structure enables them

to perform one particular kind of computation,” as they do more or less

reflexively apart from “extremely hostile environments.” Human language

acquisition is instinctive in this sense, based on a specialized

“language organ.” This “modular view of learning” Gallistel takes to be

“the norm these days in neuroscience” (Gallistel 1997:77, 82, 86±89).

Rephrasing in terms I have sometimes used (Chomsky 1975), the “learning

mechanisms” are dedicated systems LT(O, D) (learning theories for

organism O in domain D); among them is LT(Human, Language), the

specialized “language organ,” the faculty of language FL. Its initial

state is an expression of the genes, comparable to the initial state of

the human visual system, and appears to be a common human possession to

close approximation. Accordingly, a typical child will acquire any

language under appropriate conditions, even under severe deficit and in

“hostile environments.” The initial state changes under the triggering

and shaping effect of experience, and internally determined processes of

maturation, yielding later states that seem to stabilize at several

stages, finally at about puberty. We can think of the initial state of

FL as a device that maps experience into state L attained, hence a

language acquisition device (LAD). The existence of such a LAD is

sometimes regarded as controversial, but it is no more so than the

(equivalent) assumption that there is a dedicated language module that

accounts for the linguistic development of an infant as distinct from

that of her pet kitten (or chimpanzee, or whatever), given essentially

the same experience. Even the most extreme “radical behaviorist”

speculations presuppose (often tacitly) that a child can somehow

distinguish linguistic materials from the rest of the confusion around

it, hence postulating the existence of FL = LAD. As discussion of

language acquisition becomes more substantive, it moves to assumptions

about FL that are richer and more domain specific, without exception to

my knowledge.

It may be useful to distinguish modularity understood in these terms

from Jerry Fodor’s influential ideas (Fodor 1983). Fodorian modularity

is concerned primarily with input systems. In contrast, modularity in

the sense just described is concerned with cognitive systems, their

initial states and states attained, and the ways these states enter into

perception and action. Whether the processing (input/output) systems

that access such cognitive states are modular in Fodor’s sense is a

distinct question.

As Fodor puts the matter, “The perceptual system for a language comes to

be viewed as containing quite an elaborate theory of the objects in its

domain; perhaps a theory couched in terms of a grammar of the language”

(and the same should hold for the systems of language use) (Fodor

1983:51). I would prefer a somewhat different formulation: Jones’s

language L is a state of FL, and Jones’s perceptual (and production)

systems access L. Theories of L (and FL) are what the linguist seeks to

discover; adapting traditional terms, the linguist’s theory of Jones’s L

can be called a grammar of L, and the theory of FL can be called

universal grammar, but it is the linguist, not Jones, who has a theory

of L and FL, a theory that is partial and partially erroneous. Jones has

L, but no theory of L (except what he may believe about the language he

has, beliefs that have no privileged status, any more than what Jones

may believe about his visual system or problem-solving capacities).

When we look more closely, we see that more is involved here than choice

of terminology, but let us put that aside. Clearly the notions of

modularity are different, as are the questions raised, though they are

not incompatible, except perhaps in one sense: FL and L appear to be

“central systems” in Fodor’s framework, distinctive components of the

central “architecture of mind,” so that the “central systems”

would not be unstructured (what Fodor calls “Quinean and isotropic”),

containing only domain-neutral properties of inference, reasoning, and

thought generally.

For language, this “biolinguistic” approach seems to me very sound (see

Jenkins, 2000, on the state of the art). But elementary questions remain

to be answered before there will be much hope of solving problems about

the cellular implementation of recursive procedures, and mechanisms for

using them, that appear to have evolved recently and to be isolated in

the biological world in essential respects.

Problems become still more severe when we discover that there is debate,

which appears to be substantive, as to how to interpret the recursive

procedure. There are so-called derivational and representational

interpretations, and subvarieties of each. And although on the surface

the debates have the character of a debate over whether 25 is 5 squared

or 5 is the square root of 25, when we look more closely we find

empirical evidence that seems to support one or another view.

These are difficult and subtle questions, at the borders of inquiry, but

the striking fact is that they do appear to be empirical questions. The

fact is puzzling. It is far from clear what it means to say that a

recursive procedure has a particular interpretation for a cognitive

system, not a different interpretation formally equivalent to the first;

or how such distinctions — whatever they mean — might be implemented at

the cellular level. We find ourselves in a situation reminiscent of that

of post-Newtonian scientists — for example, Lavoisier, who believed that

“the number and nature of elements” is “an unsolvable problem, capable

of an infinity of solutions none of which probably accord with Nature.”

“It seems extremely probable that we know nothing at all about ... [the]

... indivisible atoms of which matter is composed,” and never will, he

thought (Lavoisier, quoted in Brock 1992:129).

Some have reacted to these problems much in the way that leading natural

scientists did in the era before unification of chemistry and physics.

One influential proposal is the computer model of the mind. According to

this view, cognitive science “aims for a level of description of the

mind that abstracts away from the biological realizations of cognitive

structures.” It does so in principle, not because of lack of

understanding we hope will be temporary, or to solve some problem for

which implementation is irrelevant, or in order to explore the

consequences of certain assumptions. Rather, for cognitive science it

does not matter” whether one chooses an implementation in “gray matter

... , switches, or cats and mice.” Psychology is therefore not a

biological science, and given the “anti-biological bias” of this

approach, if we can construct automata in “our computational image,”

performing as we do by some criterion, then “we will naturally feel that

the most compelling theory of the mind is one that is general enough to

apply to both them and us,” as distinct from “a biological theory of the

human mind [which] will not apply to these machines” (Block 1990:261).

So conceived, cognitive science is nonnaturalistic, not part of the

natural sciences in principle. Notice that this resembles the view of

chemistry, not long ago, as a calculating device, but is far more

extreme: no one proposed that “the most compelling theory of chemistry

is one general enough to apply” to worlds with different physical laws

than ours, but with phenomena that are similar by some criterion. One

might ask why there should be such a radical departure from the practice

of the sciences when we turn to the study of mind.

The account of the computer model is a fair description of much of the

work in the cognitive sciences; for example, work that seeks to answer

questions framed in terms of the Turing test — a serious

misinterpretation of Turing’s proposals, I think, but that is another

matter. For the computer model of the mind, the problems I mentioned do

not arise. It also follows that nothing discovered about the brain will

matter for the cognitive sciences. For example, if it is some day

discovered that one interpretation of the recursive procedure can be

implemented at the cellular level, and another cannot, the result will

be irrelevant to the study of human language.

That does not seem to me to be a wise course.

Another approach, influential in contemporary philosophy of mind and

theoretical cognitive science, is to hold that the relation of the

mental to the physical is not reducibility but supervenience: any change

in mental events or states entails a “physical change,” though not

conversely, and there is nothing more specific to say. The

preunification debates over chemistry could be rephrased in these terms:

those denying the “reality” of chemistry could have held that chemical

properties supervene on physical properties, but are not reducible to

them. That would have been an error, for reasons already mentioned: the

right physical properties had not yet been discovered. Once they were,

talk of supervenience becomes irrelevant and we move toward unification.

The same stance seems to me reasonable in this case.

Still another approach is outlined in a highly regarded book by

neuroscientist Terrence Deacon (1997) on language and the brain. He

proposes that students of language and its acquisition who are concerned

with states of a genetically determined “module” of the brain have

overlooked another possibility: “that the extra support for language

learning,” beyond the data of experience, “is vested neither in the

brain of the child nor in the brains of parents or teachers, but outside

brains, in language itself.” Language and languages are extrahuman.

“Languages have evolved with respect to human brains”; “The world’s

languages evolved spontaneously” and have “become better and better

adapted to people,” apparently the way prey and predator coevolve in the

familiar cycle. Language and languages are not only extrahuman organisms

but are outside the biological world altogether, it would seem. Infants

are “predisposed to learn human languages” and “are strongly biased in

their choices” of “the rules underlying language,” but it is a mistake

to try to determine what these predispositions are, and to seek their

realization in brain mechanisms (in which case the extrahuman organisms

vanish from the scene). It is worse than a mistake: to pursue the course

of normal science in this case is to resort to a “magician’s trick”

(Deacon 1997: chap. 4).

I have been giving quotations, because I have no idea what this means,

and understanding is not helped by Deacon’s unrecognizable account of

“linguistics” and of work allegedly related to it. Whatever the meaning

may be, the conclusion seems to be that it is a waste of time to

investigate the brain to discover the nature of human language, and that

studies of language must be about the extrahuman — and apparently

extrabiological — organisms that coevolved with humans and somehow

“latch on” to them, English latching on some, Japanese to others.

I do not recommend this course either; in fact could not, because I do

not understand it.

Within philosophy of language and mind, and a good part of theoretical

cognitive science, the consensus view also takes language to be

something outside the brain: it is a property of some social organism, a

“community” or a “culture” or a “nation.” Each language exists

“independently of any particular speakers,” who have a “partial, and

partially erroneous, grasp of the language.” The child “borrows” the

language from the community, as a “consumer.” The real sound and meaning

of the words of English are those of the lender and are therefore

outside of my head, I may not know them, and it would be a strange

accident if anyone knew them for “all of English.” I am quoting several

outstanding philosophers of mind and language, but the assumptions are

quite general, in one or another form.

Ordinary ways of talking about language reinforce such conceptions. Thus

we say that a child is learning English but has not yet reached the

goal. What the child has acquired is not a language at all: we have no

name for whatever it is that a four-year-old has acquired. The child has

a “partial, and partially erroneous, grasp” of English. So does

everyone, in fact.

Learning is an achievement. The learner has a goal, a target: you aim

for the goal and if you have not reached it, you have not yet learned,

though you may be on the way. Formal learning theory adopts a similar

picture: it asks about the conditions that must be satisfed for the

learner to reach the target, which is set independently. It also takes

thè‘language” to be a set of sentences, not the recursive procedure for

generating expressions in the sense of the empirical study of language

(often called the internalized grammar, a usage that has sometimes been

misleading). In English, unlike similar languages, one also speaks of

“knowing a language.” That usage has led to the conclusion that some

cognitive relation holds between the person and the language, which is

therefore outside the person: we do not know a state of our brains.

None of this has any biological interpretation. Furthermore, much of it

seems to me resistant to any explicit and coherent interpretation. That

is no problem for ordinary language, of course. But there is no reason

to suppose that common usage of such terms as language or learning (or

belief or numerous others like them), or others belonging to similar

semantic fields in other linguistic systems, will find any place in

attempts to understand the aspects of the world to which they pertain.

Likewise, no one expects the commonsense terms energy or liquid or life

to play a role in the sciences, beyond a rudimentary level. The issues

are much the same.

There have been important results in the study of animal behavior and

communication in a variety of species, generally in abstraction from the

cellular level. How much such work advances us toward an understanding

of human higher mental faculties seems unclear. Gallistel introduced a

compendium of review articles on the topic a few years ago by arguing

that representations play a key role in animal behavior and cognition.

Here representation is to be understood in the mathematical sense of

isomorphism: a one-one relation between mind/brain processes and “an

aspect of the environment to which these processes adapt the animal’s

behavior”-for example, when an ant represents the corpse of a conspecifc

by its odor (Gallistel 1990b:2).

The results are extremely interesting, but it is not clear that they

offer useful analogues for human conceptual representation,

specifically, for what is called phonetic or semantic representation.

They do not seem to provide a useful approach to the relation of

phonology to motions of molecules, and research does not follow this

course. Personally, I think the picture is more misleading than helpful

on the meaning side of language, contrary to most contemporary work

about meaning and reference.

Here particularly, I think we can learn a good deal from work on these

topics in the early modern period, now mostly forgotten. When we turn to

the organization and generation of representations, analogies break down

very quickly beyond the most superficial level.

The “biolinguistic” approach is at the core of the modern study of

language, at least as I understand it. The program was formulated with

relative clarity about forty years ago. As soon as the first attempts

were made to develop recursive procedures to characterize linguistic

expressions, it instantly became clear that little was known, even about

well-studied languages. Existing dictionaries and grammars, however

extensive, provide little more than hints and a few generalizations.

They tacitly rely on the unanalyzed “intelligence of the reader” to fill

in the rest, which is just about everything. Furthermore the

generalizations are often misleading or worse, because they are limited

to observed phenomena and their apparent structural arrangements

-morphological paradigms, for example. As has been discovered everywhere

in the sciences, these patterns mask principles of a different character

that cannot be detected directly in arrangement of phenomena.

But filling in the huge gaps and finding the real principles and

generalizations is only part of the problem. It is also necessary to

account for the fact that all children acquire their languages: their

own private languages, of course, from this point of view, just as their

visual systems are their own, not a target they are attempting to reach

or a community possession or some extrahuman organism that coevolved

with them.

It quickly became clear that the two basic goals are in conflict. To

describe the state attained, it seemed necessary to postulate a rich and

complex system of rules, specific to the language and even specific to

particular grammatical constructions: relative clauses in Japanese, verb

phrases in Swahili, and so on. But the most elementary observations

about acquisition of language showed that that cannot be even close to

accurate. The child has insufficient (or no) evidence for elementary

properties of language that were discovered, so it must be that they

reflect the initial state of the language faculty, which provides the

basic framework for languages, allowing only the kinds of marginal

variation that experience could determine.

The tension between these two goals set the immediate research agenda

forty years ago. The obvious approach was to try to abstract general

properties of the complex states attained, attribute them to the initial

state, and show that the residue is indeed simple enough to be acquired

with available experience. Many such efforts more or less crystallized

fifteen to twenty years ago in what is sometimes called the

principles-and-parameters approach. The basic principles of language are

properties of the initial state; the parameters can vary in limited ways

and are set by experience.

To a large extent, the parameters furthermore seem to be lexical, in

fact properties of a small subcomponent of the lexicon, particularly

inflectional morphology. Some recent work suggests that an even smaller

subpart of inflectional morphology may be playing the central role in

determining both the functioning and the superficial variety of

language: inflectional morphology that lacks semantic interpretation.

This narrow subcomponent may also be what is involved in the ubiquitous

and rather surprising “dislocation” property of human language: the fact

that phrases are pronounced in one position in a sentence, but

understood as if they were in a different position, where their semantic

role would be transparent.

Here there is some convergence with other approaches, including work by

Alfonso Caramazza and others. These investigators have found

dissociation of inflectional morphology from other linguistic processes

in aphasia, and have produced some intriguing results that suggest that

dislocation too may be dissociated (Caramazza 1997). A result of

particular interest for the study of language is the distinction that

Grodzinsky and Finkel report between dislocation of phrasal categories

and of lexical categories (Grodzinsky 1990; Grodzinsky and Finkel 1998).

That result would tend to confirm some recent ideas about distinctions

of basic semantic, phonological, and syntactic properties of these two

types of dislocation: head movement and XP-movement in technical terms.

Other recent linguistic work has led to a sharper focus on the

“interface” relations between extralinguistic systems and the cognitive

system of language-that is, the recursive procedure that generates

expressions. The extralinguistic systems include sensorimotor and

conceptual systems, which have their own properties independent of the

language faculty. These systems establish what we might call “minimal

design specifications” for the language faculty. To be usable at all, a

language must be “legible” at the interface: the expressions it

generates must consist of properties that can be interpreted by these

external systems.

One thesis, which seems to me much more plausible than anyone could have

guessed a few years ago, is that these minimal design specifications are

also maximal conditions in nontrivial respects. That is, language is a

kind of optimal solution to the minimal conditions it must meet to be

usable at all. This strong minimalist thesis, as it is sometimes called,

is highly controversial, and should be: it would be quite surprising if

something like that turned out to be true. I think the research program

stimulated by this thesis is promising. It has already yielded some

interesting and surprising results, which may have suggestive

implications for the inquiry into language and the brain. This thesis

brings to prominence an apparent property of language that I already

mentioned, and that might prove fundamental: the significance of

semantically uninterpretable morphological features, and their special

role in language variety and function, including the dislocation

property.

Other consequences also suggest research directions that might be

feasible and productive. One major question of linguistic research, from

every perspective, is what George Miller years ago called chunking: what

are the units that constitute expressions, for storage of information,

and for access in production, perception, retrieval, and other

operations? Some are reasonably clear: something like syllables, words,

larger phrases of various kinds. Others that seem crucial are harder to

detect in the stream of speech: phonological and morphological elements,

dislocation structures, and semantically relevant configurations that

may be scarcely reflected in the sound of an expression, sometimes not

at all, and in this sense are “abstract.” That is, these elements are

really present in the internal computation, but with only indirect

effects, if any, on the phonetic output.

Very recent work pursuing minimalist theses suggests that two types of

abstract phrases are implicated in a special way in linguistic

processes. The two types are the closest syntactic analogues to full

propositions, in the semantic sense. In more technical terms, these are

clauses with tense/event structure as well as force-mood indicators, and

verbal phrases with a full argument structure: full CPs and verbal

phrases with an external argument, but not finite or infinitival

Tense-headed phrases without complementizer or verbal phrases without

external argument (Chomsky 2000).

It is impossible to spell out the details and the empirical basis here,

but the categories are clearly defined, and there is evidence that they

have a special role with regard to sound, meaning, and intricate

syntactic properties, including the systems of uninterpretable elements,

dislocation, and the derivational interpretation of the recursive

function. It would be extremely interesting to see if the conclusions

could be tested by online studies of language use, or from other

approaches.

To the extent that the strong minimalist thesis holds, interface

conditions assume renewed importance. They can no longer simply be taken

for granted in some in-explicit way, as in most empirical work on

language. Their precise nature becomes a primary object of

investigation-in linguistics, in the brain sciences, in fact from every

point of view.

Exactly how the story unfolds from here depends on the actual facts of

the matter.

At the level of language and mind, there is a good deal to say, but this

is not the place. Again, I think it makes sense to think of this level

of inquiry as in principle similar to chemistry early in the twentieth

century: in principle that is, not in terms of the depth and richness of

the “bodies of doctrine” established.

A primary goal is to bring the bodies of doctrine concerning language

into closer relation with those emerging from the brain sciences and

other perspectives. We may anticipate that richer bodies of doctrine

will interact, setting significant conditions from one level of analysis

for another, perhaps ultimately converging in true unification. But we

should not mistake truisms for substantive theses, and there is no place

for dogmatism as to how the issues might move toward resolution. We know

far too little for that, and the history of modern science teaches us

lessons that I think should not be ignored.

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