Washoe and Nim Chimpsky

But they can't actually talk. I mean speak human languages.

Well, not having a human larynx is a big disadvantage. Can you swing like a chimp, leap like a leopard? Compared with them your arms and legs are pathetic.

So why do you claim they can learn to communicate?

Take Washoe. A chimp. She must be 40 years old now. She lives in Washington now, but a couple of researchers taught her some gestures based on American Sign Language.

How many words did she learn?

They say she can reliably use around a couple of hundred signs. More than that, she can make up her own.

Do all language people believe this?

Well, there are disbelievers and sceptics. Notably Herbert Terrace who experimented with teaching language to a chimp called Nim Chimpsky. And he reckoned that Nim only used language pragmatically.

Philosophically?

For practical purposes. To get something he wanted.

Meaning humans don't use language to get what they want?

They do. But they also use language to discuss ideas, which hasn't ever been observed among any animal species.
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