Machines Like Us

By Peter Hankins

This piece by Clive Wynne reviews the well-known attempts which have been made to teach chimps (or bonobos) to use language, and draws the melancholy conclusion that the net result has in the end merely confirmed that grammar is uniquely human. It seems a fair assessment to me (though I always find it difficult not to be convinced by some of the remarkable videos which have been produced), but it did provoke some thoughts that had never occurred to me in this connection before.

According to Wynne, the chimps show clear signs of recognising a number of nouns, but no sign of either putting the nouns in the right order, or recognising the significance of the order in which they have been put by humans. They cannot, in other words, distinguish between ’snake bites dog’ and ‘dog bites snake’, which is a key test of grammatical competence.

But word order is obviously not the whole story so far as grammar is concerned. One of the first things you learn in Latin is that in that language, although there may be a preferred word order, it isn’t grammatically decisive: ‘Serpens mordet canis’ means the same as ‘Canis mordet serpens’ (or ‘Mordet serpens canis’, for that matter). Perhaps apes just have trouble with grammars like that of English which rely on word order; perhaps they would do better with a language which used inflection, or some other grammatical mechanism instead? Was failure, in short, built into these experiments just as surely as it was into the doomed earlier attempts to teach them to speak?

Two quite different languages were involved in the different experiments: Washoe and other chimps were taught ASL, a sign language used by deaf humans; Kanzi and others were taught to communicate in specially-created lexigrams, symbols arranged on a keyboard, though the experimenters apparently used spoken English for the most part.

I don’t know much about ASL, but it does appear to use word order, albeit a different one from that in normal English; typically the topic is mentioned first, followed a comment. You can do this sort of thing in English of course (’That snake -- the dog bit it.’), but isn’t standard. If you want to specify a time in ASL, which might be done with tenses in English, you should mention it first, before the topic. In making your comment, the word order appears to be similar to the standard English one, though there may be some degree of flexibility. My impression is that ASL users would tend to break down the information they’re conveying into smaller chunks than would be normal in English, taking a clause at a time to help minimise ambiguity. There is something called inflection in ASL, but it isn’t the kind of conjugation and declension we’re used to in Latin, and doesn’t play the same grammatical role. In fact, one important grammatical indicator in ASL is facial expression - a possible problem for the chimps, although they could presumably manage some of the basic head-tilting and eye-brow (alright, brow-ridge) raising.

With lexigrams. the relationship to standard English is closer: each of the 384 lexigrams is equivalent to an English word, and indeed some consist of the word written in a particular shape with particular colours. This obviously makes things easy for the experimenters and in some ways for the bonobos, who would otherwise be faced with learning two languages, heard English and spoken lexigram. The grammar involved is therefore essentially English, and if anything the use of lexigrams makes word order even more crucial, since verbs are necessarily invariant and there are no plurals: so we don’t even get the kind of extra clues we might have in an English sentence like ‘The dog bites the snakes’.

Prima facie then, it does seem to me that unless the chimps were naturally at ease with using English-style word order as their sole grammatical tool, they were actually given little scope to demonstrate grammatical abilities by any of these experiments. We can perhaps follow the implications a little further. ASL is not very much like ordinary English in its grammar or structure. The adoption of a different channel of communication by deaf people appears to have called for a very different language. It seems natural to suppose, then, that if we require even more radically different channels to communicate with chimps we need a language even more remote from English. Perhaps both ASL and lexigrams are too strongly adapted for human use: true communication may require a form of language which is novel and as difficult for human beings to learn as the chimps; one in fact which might require some rethinking of how grammar can be expressed (something similar had to happen before it was accepted that ASL and other sign languages had true grammar). But if merely understanding this hypothetical language would be dauntingly difficult for us, it hardly seems probable that we could construct it in the first place.

The only way such a language could be constructed, I think, is if the chimps were able to make an equal contribution from their side, rather than being captives drilled in an essentially human style of communication. If a human and chimp community enjoyed a close but free relationship of real importance to both, possibly based on trade or similar relations of mutual benefit, perhaps the differing conventions of different species could be shared and a kind of pidgin developed, as happened all over the world when Western traders first appeared -- although this time it would have to be a non-vocal one. The chances of anything like this happening, if not zero in any case are of course remote, and growing less all the time, so sadly the chances are that if chimps do after all have some grammatical ability, we’ll never really know about it.

Peter Hankins is author of the Conscious Entities weblog.