If we could re-run our own evolution, I’d be prepared to bet that swearing was one of the first features of human language. That’s because our closest cousins, chimpanzees, are fond of a bit of swearing too. What’s more, swearing seems to spontaneously emerge just as soon as they - and we - have language and a taboo.
There have been several attempts to teach chimpanzees sign language. The most succesful by far are the heroic ones run by behaviourists Roger and Deborah Fouts. They were committed enough to foster several, living with them as if they were members of their own family, for many years. They started in 1966 with a ten month old fosterling, Washoe, who they immediately began to teach sign language and to potty train.
Almost immediately, she started to use the sign DIRTY, intended for all things scatalogical, as an insult and an interjection. She spontaneously developed a potty mouth.
It might seem like a stretch to talk about chimpanzees as having taboos, but Washoe and the rest of her chimpanzee family became incredibly fastidious about their toilet habits. Washoe was so thoroughly toilet trained that that she wouldn’t even defecate in the woods, holding it in until one of the humans in the group offered her an empty coffee can to use as a potty.
We also know that toilet-trained chimpanzees lie if they’re caught accidentally (or deliberately) making a mess away from their toilet. DIRTY GOOD is the name that Washoe herself came up with for her potty. This name, which she invented herself, shows how nuanced her understanding of the excretion taboo was: pooing in a potty is necessary and acceptable, but crap out of context is shameful and wrong.
Washoe and the other chimpanzees began to use DIRTY as an insult, when they were angry or frustrated. The humans never used it that way about the chimpanzees; the use of DIRTY as a curse by the chimpanzees was spontaneous. For example Washoe signed DIRTY ROGER when Fouts wouldn’t let her out of her cage and DIRTY MONKEY at a macaque who threatened her.
It’s my hypothesis that the combination of learning a language and the excretion taboo is all it takes for swearing to emerge. That said, I can’t imagine anyone being brave enough to test my conjecture. In the wild, chimpanzees deliberately defecate on humans as a way of marking their territory, so trying to recreate the Fouts’ study without the potty training step would be a grim challenge.
English speaking toddlers tend to show a similar pattern, however, commonly using “poo face” or “doodoo head” as soon as they’re potty trained - again, not something they’re likely to have heard from parents. I can’t wait for my daughter to reach that stage: research from the 1930s shows that among toddlers, the development of a pottymouth comes with at least one fringe benefit. Swearing replaces biting, hitting, screaming and breath-holding as ways of externalising strong feelings in human children, and in chimpanzees too.
The chimpanzees only seem to have had the one sign that they used as swearing - probably because it was their only taboo. When Washoe hit adolescence she began masturbating, but the research team decided that discretion was the better part of valour and didn’t intervene, so there was no equivalent of the copulatory taboo that accounts for so much human swearing.
However, DIRTY was deployed with impressive flexibility. In the same way that the f-word can be hissed, shouted or spat, DIRTY was be signed with differing emphasis by the chimpanzees depending on the intensity of their feelings. The sign is made by bringing the back of the wrist up underneath the chin. When the chimpanzees were extremely angry they would make the sign so forcefully that the clacking noise of their teeth could be heard all through the lab. That passion and fury reminds me of the way that the middle digit can be brandished or the fist pounded into the crook of the elbow.
Until I started writing Swearing is Good for You, I didn't realise how much research has been done with chimpanzees. I never knew that chimpanzees are self-aware enough to communicate, and have a complex enough internal life to recognise taboos, which they then use to swear. We can deduce from this that chimpanzees have a working theory of mind that allows them to know that swearing will have an impact on the person on the receiving end. And they experience strong emotions, which drive them to swear.
For years, in my discipline of artificial intelligence, we’ve been debating the ethics of how we should treat non-human intelligence if we ever manage to create it, but the way that chimpanzees swear is enough to convince me that non-human intelligence already exists.
And, if we ever create artificial intelligence, it won't function in an unbounded domain until it is able to experience something like our emotions; emotions are the fast filter on the swirling sea of stimuli that surrounds us. Machine intelligence needs emotion to guide cognition. So, when AIs do start to have feelings, it's probably in our own best interests that we let them learn to swear.
Dr Emma Byrne is an artificial intelligence researcher and the author of Swearing is Good for You (Profile Books, November 2017)
This article was originally published by WIRED UK
