The Language Instinct: How the Mind Creates Language

by Steven Pinker

  Babies continue to learn the sounds of their language throughout the first year. By six months, they are beginning to lump together the distinct sounds that their language collapses into a single phoneme, while continuing to discriminate equivalently distinct ones that their language keeps separate. By ten months they are no longer universal phoneticians but have turned into their parents; they do not distinguish Czech or Inslekampx phonemes unless they are Czech or Inslekampx babies. Babies make this transition before they produce or understand words, so their learning cannot depend on correlating sound with meaning. That is, they cannot be listening for the difference in sound between a word they think means bit and a word they think means beet, because they have learned neither word. They must be sorting the sounds directly, somehow tuning their speech analysis module to deliver the phonemes used in their language. The module can then serve as the front end of the system that learns words and grammar.

  During the first year, babies also get their speech production systems geared up. First, ontogeny recapitulates phylogeny. A newborn has a vocal tract like a nonhuman mammal. The larynx comes up like a periscope and engages the nasal passage, forcing the infant to breathe through the nose and making it anatomically possible to drink and breathe at the same time. By three months the larynx has descended deep into the throat, opening up the cavity behind the tongue (the pharynx) that allows the tongue to move forwards and backwards and produce the variety of vowel sounds used by adults.

  Not much of linguistic interest happens during the first two months, when babies produce the cries, grunts, sighs, clicks, stops, and pops associated with breathing, feeding, and fussing, or even during the next three, when coos and laughs are added. Between five and seven months babies begin to play with sounds, rather than using them to express their physical and emotional states, and their sequences of clicks, hums, glides, trills, hisses, and smacks begin to sound like consonants and vowels. Between seven and eight months they suddenly begin to babble in real syllables like ba-ba-ba, neh-neh-neh, and dee-dee-dee. The sounds are the same in all languages, and consist of the phonemes and syllable patterns that are most common across languages. By the end of the first year, babies vary their syllables, like neh-nee, da-dee, and meh-neh, and produce that really cute sentencelike gibberish.

  In recent years pediatricians have saved the lives of many babies with breathing abnormalities by inserting a tube into their tracheas (the pediatricians are trained on cats, whose airways are similar), or by surgically opening a hole in their trachea below the larynx. The infants are then unable to make voiced sounds during the normal period of babbling. When the normal airway is restored in the second year of life, those infants are seriously retarded in speech development, though they eventually catch up, with no permanent problems. Deaf children’s babbling is later and simpler—though if their parents use sign language, they babble, on schedule, with their hands!

  Why is babbling so important? The infant is like a person who has been given a complicated piece of audio equipment bristling with unlabeled knobs and switches but missing the instruction manual. In such situations people resort to what hackers call frobbing—fiddling aimlessly with the controls to see what happens. The infant has been given a set of neural commands that can move the articulators every which way, with wildly varying effects on the sound. By listening to their own babbling, babies in effect write their own instruction manual; they learn how much to move which muscle in which way to make which change in the sound. This is a prerequisite to duplicating the speech of their parents. Some computer scientists, inspired by the infant, believe that a good robot should learn an internal software model of its articulators by observing the consequences of its own babbling and flailing.

  Shortly before their first birthday, babies begin to understand words, and around that birthday, they start to produce them. Words are usually produced in isolation; this one-word stage can last from two months to a year. For over a century, and all over the globe, scientists have kept diaries of their infants’ first words, and the lists are almost identical. About half the words are for objects: food (juice, cookie), body parts (eye, nose), clothing (diaper, sock), vehicles (car, boat), toys (doll, block), household items (bottle, light), animals (dog, kitty), and people (dada, baby). (My nephew Eric’s first word was Batman.) There are words for actions, motions, and routines, like up, off, open, peekaboo, eat, and go, and modifiers, like hot, all gone, more, dirty, and cold. Finally, there are routines used in social interaction, like yes, no, want, bye-bye, and hi—a few of which, like look at that and what is that, are words in the sense of listemes (memorized chunks), but not, at least for the adult, words in the sense of morphological products and syntactic atoms. Children differ in how much they name objects or engage in social interaction using memorized routines. Psychologists have spent a lot of time speculating about the causes of those differences (sex, age, birth order, and socioeconomic status have all been examined), but the most plausible to my mind is that babies are people, only smaller. Some are interested in objects, others like to shmooze.

  Since word boundaries do not physically exist, it is remarkable that children are so good at finding them. A baby is like the dog being yelled at in the two-panel cartoon by Gary Larson:

  WHAT WE SAY TO DOGS: “Okay, Ginger! I’ve had it! You stay out of the garbage! Understand, Ginger? Stay out of the garbage, or else!”

  WHAT THEY HEAR: “Blah blah GINGER blah blah blah blah blah blah blah blah GINGER blah blah blah blah blah.”

  Presumably children record some words parents use in isolation, or in stressed final positions, like Look-at-the BOTTLE. Then they look for matches to these words in longer stretches of speech, and find other words by extracting the residues in between the matched portions. Occasionally there are near misses, providing great entertainment to family members:

  I don’t want to go to your ami. [from Miami]

  I am heyv! [from Behave!]

  Daddy, when you go tinkle you’re an eight, and when I go tinkle I’m an eight, right? [from urinate]

  I know I sound like Larry, but who’s Gitis? [from laryngitis]

  Daddy, why do you call your character Sam Alone? [from Sam Malone, the bartender in Cheers]

  The ants are my friends, they’re blowing in the wind. [from The answer, my friend, is blowing in the wind]

  But these errors are surprisingly rare, and of course adults occasionally make them too, as in the Pullet Surprise and doggy-dog world of Chapter 6. In an episode of the television show Hill Street Blues, police officer JD Larue began to flirt with a pretty high school student. His partner, Neal Washington, said, “I have only three words to say to you, JD. Statue. Tory. Rape.”

  Around eighteen months, language takes off. Vocabulary growth jumps to the new-word-every-two-hours minimum rate that the child will maintain through adolescence. And syntax begins, with strings of the minimum length that allows it: two. Here are some examples:

  All dry.

  I sit.

  No pee.

  More cereal.

  Other pocket.

  Mail come.

  Our car.

  All messy.

  I shut.

  See baby.

  More hot.

  Boot off.

  Airplane allgone.

  Papa away.

  All wet.

  No bed.

  See pretty.

  Hi Calico.

  Siren by.

  Bye-bye car.

  Dry pants.

  Children’s two-word combinations are so similar in meaning the world over that they read as translations of one another. Children announce when objects appear, disappear, and move about, point out their properties and owners, comment on people doing things and seeing things, reject and request objects and activities, and ask about who, what, and where. These microsentences already reflect the language being acquired: in ninety-five percent of them, the words are properly ordered.

  There is more going on in children�
��s minds than in what comes out of their mouths. Even before they put two words together, babies can comprehend a sentence using its syntax. For example, in one experiment, babies who spoke only in single words were seated in front of two television screens, each of which featured a pair of adults improbably dressed up as Cookie Monster and Big Bird from Sesame Street. One screen showed Cookie Monster tickling Big Bird; the other showed Big Bird tickling Cookie Monster. A voiceover said, “OH LOOK!!! BIG BIRD IS TICKLING COOKIE MONSTER!! FIND BIG BIRD TICKLING COOKIE MONSTER!!” (or vice versa). The children must have understood the meaning of the ordering of subject, verb, and object—they looked more at the screen that depicted the sentence in the voiceover.

  When children do put words together, the words seem to meet up with a bottleneck at the output end. Children’s two-and-three-word utterances look like samples drawn from longer potential sentences expressing a complete and more complicated idea. For example, the psychologist Roger Brown noted that although the children he studied never produced a sentence as complicated as Mother gave John lunch in the kitchen, they did produce strings containing all of its components, and in the correct order:

  AGENT: (Mother

  ACTION: gave

  RECIPIENT: John

  OBJECT: lunch

  LOCATION: in the kitchen.)

  AGENT: Mommy

  ACTION: fix.

  RECIPIENT:

  OBJECT:

  LOCATION:

  AGENT: Mommy

  ACTION:

  RECIPIENT:

  OBJECT: pumpkin.

  LOCATION:

  AGENT: Baby

  ACTION:

  RECIPIENT:

  OBJECT:

  LOCATION: table

  AGENT: Give

  ACTION:

  RECIPIENT: doggie.

  OBJECT:

  LOCATION:

  AGENT:

  ACTION: Put

  RECIPIENT:

  OBJECT: light.

  LOCATION:

  AGENT:

  ACTION: Put

  RECIPIENT:

  OBJECT:

  LOCATION: floor.

  AGENT: I

  ACTION: ride

  RECIPIENT:

  OBJECT: horsie.

  LOCATION:

  AGENT: Tractor

  ACTION: go

  RECIPIENT:

  OBJECT:

  LOCATION: floor.

  AGENT:

  ACTION: Give

  RECIPIENT: doggie

  OBJECT: paper.

  LOCATION:

  AGENT:

  ACTION: Put

  RECIPIENT:

  OBJECT: truck

  LOCATION: window.

  AGENT: Adam

  ACTION: put

  RECIPIENT:

  OBJECT: it

  LOCATION: box.

  If we divide language development into somewhat arbitrary stages, like Syllable Babbling, Gibberish Babbling, One-Word Utterances, and Two-Word Strings, the next stage would have to be called All Hell Breaks Loose. Between the late twos and the mid-threes, children’s language blooms into fluent grammatical conversation so rapidly that it overwhelms the researchers who study it, and no one has worked out the exact sequence. Sentence length increases steadily, and because grammar is a discrete combinatorial system, the number of syntactic types increases exponentially, doubling every month, reaching the thousands before the third birthday. You can get a feel for this explosion by seeing how the speech of a little boy called Adam grows in sophistication over the period of a year, starting with his early word combinations at the age of two years and three months (“2;3”):

  2;3: Play checkers. Big drum. I got horn. A bunny-rabbit walk.

  2;4: See marching bear go? Screw part machine. That busy bulldozer truck.

  2;5: Now put boots on. Where wrench go? Mommy talking bout lady. What that paper clip doing?

  2;6: Write a piece a paper. What that egg doing? I lost a shoe. No, I don’t want to sit seat.

  2;7 Where piece a paper go? Ursula has a boot on. Going to see kitten. Put the cigarette down. Dropped a rubber band. Shadow has hat just like that. Rintintin don’t fly, Mommy.

  2;8: Let me get down with the boots on. Don’t be afraid a horses. How tiger be so healthy and fly like kite? Joshua throw like a penguin.

  2;9: Where Mommy keep her pocket book? Show you something funny. Just like turtle make mud pie.

  2;10: Look at that train Ursula brought. I simply don’t want put in chair. You don’t have paper. Do you want little bit, Cromer? I can’t wear it tomorrow.

  2;11: That birdie hopping by Missouri in bag. Do want some pie on your face? Why you mixing baby chocolate? I finish drinking all up down my throat. I said why not you coming in? Look at that piece a paper and tell it. Do you want me tie that round? We going turn light on so you can’t see.

  3;0: I going come in fourteen minutes. I going wear that to wedding. I see what happens. I have to save them now. Those are not strong mens. They are going sleep in wintertime. You dress me up like a baby elephant.

  3;1: I like to play with something else. You know how to put it back together. I gon’ make it like a rocket to blast off with. I put another one on the floor. You went to Boston University? You want to give me some carrots and some beans? Press the button and catch it, sir. I want some other peanuts. Why you put the pacifier in his mouth? Doggies like to climb up.

  3;2: So it can’t be cleaned? I broke my racing car. Do you know the lights wents off? What happened to the bridge? When it’s got a flat tire it’s need a go to the station. I dream sometimes. I’m going to mail this so the letter can’t come off. I want to have some espresso. The sun is not too bright. Can I have some sugar? Can I put my head in the mailbox so the mailman can know where I are and put me in the mailbox? Can I keep the screwdriver just like a carpenter keep the screwdriver?

  Normal children can differ by a year or more in their rate of language development, though the stages they pass through are generally the same regardless of how stretched out or compressed. I chose to show you Adam’s speech because his language development is rather slow compared with other children’s. Eve, another child Brown studied, was speaking in sentences like this before she was two:

  I got peanut butter on the paddle.

  I sit in my high chair yesterday.

  Fraser, the doll’s not in your briefcase.

  Fix it with the scissor.

  Sue making more coffee for Fraser.

  Her stages of language development were telescoped into just a few months.

  Many things are going on during this explosion. Children’s sentences are getting not only longer but more complex, with deeper, bushier trees, because the children can embed one constituent inside another. Whereas before they might have said Give doggie paper (a three-branch verb phrase) and Big doggie (a two-branch noun phrase), they now say Give big doggie paper, with the two-branch NP embedded inside the middle branch of three-branch VP. The earlier sentences resembled telegrams, missing unstressed function words like of, the, on, and does, as well as inflections like -ed, -ing, and -s. By the threes, children are using these function words more often than they omit them, many in more than ninety percent of the sentences that require them. A full range of sentence types flower—questions with words like who, what, and where, relative clauses, comparatives, negations, complements, conjunctions, and passives.

  Though many—perhaps even most—of the young three-year-old’s sentences are ungrammatical for one reason or another, we should not judge them too harshly, because there are many things that can go wrong in any single sentence. When researchers focus on one grammatical rule and count how often a child obeys it and how often he or she flouts it, the results are astonishing: for any rule you choose, three-year-olds obey it most of the time. As we have seen, children rarely scramble word order and, by the age of three, come to supply most inflections and function words in sentences that require them. Though our ears perk up when we hear errors like mens, wents, Can you b
roke those?, What he can ride in?, That’s a furniture, Button me the rest, and Going to see kitten, the errors occur in only 0.1% to 8% of the opportunities for making them; more than 90% of the time, the child is on target. The psychologist Karin Stromswold analyzed sentences containing auxiliaries from the speech of thirteen preschoolers. The auxiliary system in English (including words like can, should, must, be, have, and do) is notorious among grammarians for its complexity. There are about twenty-four billion billion logically possible combinations of auxiliaries (for instance, He have might eat; He aid, be eating), of which only a hundred are grammatical (He might have eaten; He has been eating). Stromswold wanted to count how many times children were seduced by several dozen kinds of tempting errors in the auxiliary system—that is, errors that would be natural generalizations of the sentence patterns children heard from their parents:

  PATTERN IN ADULT ENGLISH: He seems happy. Does he seem happy?

  ERROR THAT MIGHT TEMPT A CHILD: He is smiling. Does he be smiling?

  PATTERN IN ADULT ENGLISH:

  ERROR THAT MIGHT TEMPT A CHILD: She could go. Does she could go?