The Language Instinct: How the Mind Creates Language (19 page)

Function words also capture much of what makes one language grammatically different from another. Though all languages have function words, the properties of the words differ in ways that can have large effects on the structure of the sentences in the language. We have already seen one example: overt case and agreement markers in Latin allow noun phrases to be scrambled; silent ones in English force them to remain in place. Function words capture the grammatical look and feel of a language, as in these passages that use a language’s function words but none of its content words:

DER JAMMERWOCH
Es brillig war. Die schlichte Toven
Wirrten und wimmelten in Waben.

LE JASEROQUE
Il brilgue: les tôves lubricilleux
Se gyrent en vrillant dans la guave.

The effect can also be seen in passages that take the function words from one language but the content words from another, like the following pseudo-German notice that used to be posted in many university computing centers in the English-speaking world:

ACHTUNG! ALLES LOOKENSPEEPERS!

Turnabout being fair play, computer operators in Germany have posted a translation into pseudo-English:

ATTENTION

Anyone who goes to cocktail parties knows that one of Chomsky’s main contributions to intellectual life is the concept of “deep structure,” together with the “transformations” that map it onto “surface structure.” When Chomsky introduced the terms in the behaviorist climate of the early 1960s, the reaction was sensational. Deep structure came to refer to everything that was hidden, profound, universal, or meaningful, and before long there was talk of the deep structure of visual perception, stories, myths, poems, paintings, musical compositions, and so on. Anticlimactically, I must now divulge that “deep structure” is a prosaic technical gadget in grammatical theory. It is not the meaning of a sentence, nor is it what is universal across all human languages. Though universal grammar and abstract phrase structures seem to be permanent features of grammatical theory, many linguists—including, in his most recent writings, Chomsky himself—think one can do without deep structure per se. To discourage all the hype incited by the word “deep,” linguists now usually refer to it as “d-structure.” The concept is actually quite simple.

Recall that for a sentence to be well formed, the verb must get what it wants: all the roles listed in the verb’s dictionary entry must appear in their designated positions. But in many sentences, the verb does not seem to be getting what it wants. Remember that
put
requires a subject, an object, and a prepositional phrase;
He put the car
and
He put in the garage
sound incomplete. How, then, do we account for the following perfectly good sentences?

In the first sentence,
put
seems to be doing fine without an object, which is out of character. Indeed, now it rejects one:
The car was put the Toyota in the garage
is awful. In the second sentence,
put
also appears in public objectless. In the third, its obligatory prepositional phrase is missing. Does this mean we need to add new dictionary entries for
put
, allowing it to appear in some places without its object or its prepositional phrase? Obviously not, or
He put the car
and
He put in the garage
would slip back in.

In some sense, of course, the required phrases really are there—they’re just not where we expect them. In the first sentence, a passive construction, the NP
the car
, playing the role of “thing put” which ordinarily would be the object, shows up in the subject position instead. In the second sentence, a
wh
-question (that is, a question formed with
who, what, where, when
, or
why
), the “thing put” role is expressed by the word
what
and shows up at the beginning. In the third sentence, the “place” role also shows up at the beginning instead of after the object, where it ordinarily belongs.

A simple way to account for the entire pattern is to say that every sentence has two phrase structures. The phrase structure we have been talking about so far, the one defined by the super-rules, is the deep structure. Deep structure is the interface between the mental dictionary and phrase structure. In the deep structure, all the role-players for
put
appear in their expected places. Then a transformational operation can “move” a phrase to a previously unfilled slot elsewhere in the tree. That is where we find the phrase in the actual sentence. This new tree is the surface structure (now called “s-structure,” because as a mere “surface” representation it never used to get proper respect). Here are the deep structure and surface structure of a passive sentence:

In the deep structure on the left,
the car
is where the verb wanted it; in the surface structure on the right, it is where we actually hear it. In the surface structure, the position from which the phrase was moved contains an inaudible symbol that was left behind by the movement transformation, called a “trace.” The trace serves as a reminder of the role that the moved phrase is playing. It tells us that to find out what
the car
is doing in the putting event, we should look up the “object” slot in the entry for the verb
put
; that slot says “thing put.” Thanks to the trace, the surface structure contains the information needed to recover the meaning of the sentence; the original deep structure, which was used only to plug in the right sets of words from the lexicon, plays no role.

Why do languages bother with separate deep structures and surface structures? Because it takes more than just keeping the verb happy—what deep structure does—to have a usable sentence. A given concept often has to play one kind of role, defined by the verb in the verb phrase, and simultaneously a separate role, independent of the verb, defined by some other layer of the tree. Consider the difference between
Beavers build dams
and its passive,
Dams are built by beavers
. Down in the verb phrase—the level of who did what to whom—the nouns are playing the same roles in both sentences. Beavers do the building, dams get built. But up at the sentence (IP) level—the level of subject-predicate relations, of what is being asserted to be true of what—they are playing different roles. The active sentence is saying something about beavers in general, and happens to be true; the passive sentence is saying something about dams in general, and happens to be false (since some dams, like the Grand Coulee Dam, are not built by beavers). The surface structure, which puts
dams
in the sentence’s subject position but links it to a trace of its original verb phrase position, allows the cake to be both eaten and had.

The ability to move phrases around while still retaining their roles also gives the speaker of a rigid-word-order language like English a bit of wiggle room. For example, phrases that are ordinarily buried deep in the tree can be moved to early in the sentence, where they can hook up with material fresh in the listener’s mind. For example, if a play-by-play announcer has been describing Nevin Markwart’s progression down the ice, he could say
Markwart spears Gretzky!!!
But if it was Wayne Gretzky the announcer had been describing, he would say
Gretzky is speared by Markwart!!!!
Moreover, because a passive participle has the option of leaving the doer role, ordinarily the subject, unfilled in deep structure, it is useful when one wants to avoid mentioning that role altogether, as in Ronald Reagan’s evasive concession
Mistakes were made
.

Hooking up players with different roles in different scenarios is something that grammar excels at. In a
wh
-question like

the noun phrase
what
gets to live a double life. Down in the who-did-what-to-whom realm of the verb phrase, the position of the trace indicates that the entity has the role of the thing being put; up in the what-is-being-asserted-of-what realm of the sentence, the word
what
indicates that the point of the sentence is to ask the listener to provide the identity of something. If a logician were to express the meaning behind the sentence, it would be something like “For which
x
, John put
xin
the garage.” When these movement operations are combined with other components of syntax, as in
She was told by Bob to be examined by a doctor
or
Who did he say that Barry tried to convince to leave?
or
Tex is fun for anyone to tease
, the components interact to determine the meaning of the sentence in chains of deduction as intricate and precise as the workings of a fine Swiss watch.

Now that I have dissected syntax in front of you, I hope your reaction is more favorable than Eliza Doolittle’s or Jack Cade’s. At the very least I hope you are impressed at how syntax is a Darwinian “organ of extreme perfection and complication.” Syntax is complex, but the complexity is there for a reason. For our thoughts are surely even more complex, and we are limited by a mouth that can pronounce a single word at a time. Science has begun to crack the beautifully designed code that our brains use to convey complex thoughts as words and their orderings.

The workings of syntax are important for another reason. Grammar offers a clear refutation of the empiricist doctrine that there is nothing in the mind that was not first in the senses. Traces, cases, X-bars, and the other paraphernalia of syntax are colorless, odorless, and tasteless, but they, or something like them, must be a part of our unconscious mental life. This should not be surprising to a thoughtful computer scientist. There is no way one can write a halfway intelligent program without defining variables and data structures that do not directly correspond to anything in the input or output. For example, a graphics program that had to store an image of a triangle inside a circle would not store the actual keystrokes that the user typed to draw the shapes, because the same shapes could have been drawn in a different order or with a different device like a mouse or a light pen. Nor would it store the list of dots that have to be lit up to display the shapes on a video screen, because the user might later want to move the circle around and leave the triangle in place, or make the circle bigger or smaller, and one long list of dots would not allow the program to know which dots belong to the circle and which to the triangle. Instead, the shapes would be stored in some more abstract format (like the coordinates of a few defining points for each shape), a format that mirrors neither the inputs nor the outputs to the program but that can be translated to and from them when the need arises.

Grammar, a form of mental software, must have evolved under similar design specifications. Though psychologists under the influence of empiricism often suggest that grammar mirrors commands to the speech muscles, melodies in speech sounds, or mental scripts for the ways that people and things tend to interact, I think all these suggestions miss the mark. Grammar is a protocol that has to interconnect the ear, the mouth, and the mind, three very different kinds of machine. It cannot be tailored to any of them but must have an abstract logic of its own.