What do they know, and when?
A pioneering linguist, Lila Gleitman illuminated the way children learn to talk
Lila gleitman was driving her twoyearold daughter in the car when, executing a tricky turn, she advised her to “hold on tight”. The toddler responded: “Isn’t that ‘tightly’?”
It was a turningpoint in the young scholar’s career. She had already switched from English literature to classics, in which she quickly became bored of her teacher’s digressions on Athenian society (she wanted to get back to grammar). Realising that her twoyearold already had an understanding of language made Gleitman want to get into her child’s head, and those of other children. The questions that shaped her career were, as she put it, “the presidential questions” of children’s knowledge. What do they know, and when do they know it?
Gleitman, who died on August 8th at the age of 91, turned those questions into a research career that helped define psycholinguistics, a field that hardly existed before. Her early interest coincided with the emergence in the 1950s of Noam Chomsky, a frequent visitor to the University of Pennsylvania when she began taking courses there. Until then linguistics largely involved concentrating on what people said, shying away from what they might be thinking. The two scholars’ work and that of others instead considered the mental systems that might produce the sentences you hear, which are shaped by abstract rules that speakers may not even know that they know.
An early piece of Gleitman’s research, for example, investigated small children’s “telegraphic” speech, in which many words are left out: a toddler might say “throw ball” rather than “throw me the ball”. This seems to imply that the child’s knowledge is primitive. But she found that children nonetheless comply with instructions better when their parents use adultstyle English than when they mimic their offspring. She and her colleagues concluded that youngsters know more than they can say.
Parents prefer to think that they teach their children most of what they learn. But Gleitman’s work supported the idea that youngsters are somehow programmed to learn, even if what they hear from those around them is sparse and unstructured. So parents do not need to use “motherese”—her husband Henry’s term—with their children. She found that their progressive mastery of language rules had little to do with how much (or little) motherese their caregivers resorted to.
As the learning process goes on, children deploy some remarkable strategies. They often seem to correctly guess what a word means after hearing it just once. The physical environment is an obvious spur (as when they hear “dog” and see one at the same time). But how would a child guess the meaning of the verb in “I believed that he lost his keys”? Gleitman noticed that the sentence structure is identical to those with other verbs that mean similar things (ie, refer to states of mind): saw, remembered, imagined, forgot, worried and doubted. More broadly, it turned out that verbs which are similar in meaning tend to turn up in similar sentence structures. This intuitive aid helps children learn astonishingly quickly, a process she called “syntactic bootstrapping”.
Her work also had implications for the debate over whether a person’s native language strongly influences how they think—or even what they can think. She was convinced that all languages shared fundamental traits, forged by the nature of the human mind itself; the effects of using a particular one on cognition were modest and fleeting. The notion that speaking a different language entails a profoundly different way of thinking was romantic and tempting, but she would not buy it.
Asked to participate in a debate on the subject hosted by The Economist, and told that the audience would vote, she pointedly joked: “Next let’s do ‘Is 2+2 exactly 4?’” But take part she did, in her always lively fashion. Even her technical writing was witty and readable for the layperson. She had an aphoristic way of describing her conclusions: of the finding that verbs with similar meanings occur in similar sentence structures, she said “verbs of a feather flock together”.
Gleitman was also a prodigious mentor to other scholars. Many of them were women, for whom she was a pioneer, beginning her own research in the early 1960s while bringing up her own family. When her husband observed that “most great scientists are not great men”, she had a ready answer: “Yeah. For instance, I’m not a great man.”