The Chimp That Learned Sign Language

Back in the 1970s, a chimpanzee named Nim Chimpsky took part in a Columbia University research study called “Project Nim.”

Project Nim was led by Herbert Terrace, a psychologist at Columbia who was attempting to find out if a chimpanzee could learn to communicate using American Sign Language.

“Everyone knows that words are learned one at a time,” but something happens when children begin to combine words and create true language, Terrace says.

The question, he says, was, “Could Nim do this?”

A newly released book takes a look at the project, and the people involved examine the ethics of the experiment.

The name Nim Chimpsky was a twist on Noam Chomsky, the MIT linguist who theorized that language as we know it is unique to humans. Terrace wanted to disprove Chomsky’s theory and show that a chimpanzee could develop real language.

To immerse Nim in a world where he would be taught sign language in the same way a human child would, Terrace brought him to live with a family in New York City in 1973, not long after the chimp was born. There, Nim joined a sprawling, chaotic blended family with many human siblings who could teach him sign language.

Young Nim

Jennie Lee was 10 when Nim came to live with her family.

“He was coming off the plane with my mom, wrapped up in baby blankets,” Lee says. “He was this tiny newborn being who happened to be a chimp, and it was probably love at first sight.”

Nim’s surrogate mother was Stephanie LaFarge, a psychology student studying with Terrace. LaFarge carried Nim around on her body for almost two years.

It wasn’t easy to raise a chimp in a Manhattan brownstone. Nim was active, playful and strong. Soon he was breaking things all over the house. LaFarge’s husband was never comfortable with Nim, and as Nim entered his “terrible twos,” the chimp became too much of a handful.

So Terrace took Nim to live in a mansion that was part of Columbia University. By that time, Nim had learned about 125 signs. But the question remained: Was he really learning language?

Terrace doubts it. He says that while watching a video of Nim signing with a teacher, he realized that the chimp was tracking most of his teacher’s signs, imitating most of them, but he almost never made a sign spontaneously.

In the end, Terrace came to believe that Chomsky was right, that Nim would never use language the way humans do — to form sentences and express ideas.

Terrace ended the project in 1977, and Nim went to the Institute for Primate Studies in Norman, Okla., to live a very different life. He was often in a cage with other chimps.

Bob Ingersoll, who worked at the institute and got close to Nim, says that while in Oklahoma, Nim was learning how to be a chimp again. “He was with his brothers. He got to have a chimp group” and have a life that wasn’t always controlled by humans, Ingersoll says.

One of the things that made Nim remarkable, Ingersoll remembers, was his “unbelievable personality.” Nim understood humans better than any other chimp, Ingersoll recalls.

The Chimp Who Would Be Human

Research is not a secure proposition, and in 1981, all funding ended for the Oklahoma research program. There was no exit plan for the chimps.

Within a year, Nim was sold to a medical lab for tuberculosis studies. Because he was a famous chimp — who even appeared on Sesame Street and The David Susskind Show— Nim’s supporters were able to rescue him. He lived out the rest of his days at Cleveland Amory’s Black Beauty Ranch, an animal sanctuary in Texas. He died in 2000.

Many of the people involved in Nim’s life have been reflecting on their experiences and on the ethics of what they did.

And Elizabeth Hess, in a new book called Nim Chimpsky: The Chimp Who Would Be Human, interviews many of the people who were involved in Nim’s life and tells the story from differing perspectives

Lee, Nim’s surrogate sister, says she took it hard when Nim was sold to the lab.

“How do you reconcile a tiny chimp in blue blankets, drinking from a bottle and wearing Pampers. Those are the baby pictures,” she says. “And then, when he is 10 — him in a lab, in a cage, with nothing soft, nothing warm, with no people? This is my brother. This is somebody that I raised — and that the system could let this happen was shocking.”

LaFarge, Nim’s surrogate mother, says that as amazing as it was to have the experience with Nim, she now believes what happened was unethical. The project essentially tricked “him into thinking he is a human being, with no plan for protecting him,” she says.

But Terrace says that “given that people eat meat, have pets and raise horses for races,” what was done to Nim was not unethical.

Author Hess says Nim was a survivor who had a unique, charming personality.

She notes that while the debate over whether chimps have language, and what kind of language, continues, most researchers are no longer trying to teach animals our language. Instead, they focus on the myriad ways animals communicate.

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