100 YEARS OLD AND STILL PLAYING WITH CHIMPS...

APAPER was published last week in Primates, the journal of the Japan Monkey Centre, telling of experiments to see whether chimpanzees could learn to play rockpaper-scissors and if so whether they played it better than small children.

The results showed that chimps are as good as four-year-olds at rockpaper-scissors, though they were much slower at learning that scissors beat paper. Wishing to confirm the observations of the Kyoto and Beijingbased researchers, I rang up a chimpanzee for a chat.

“Before we go on,” he said as soon as I had explained what I wanted to talk about, “I must take issue with something you just said. We weren’t slow in learning that scissors beat paper because of any conceptual difficulty. It was just that we had already been taught that rock beat scissors and paper beat rock. It thus seemed reasonable to deduce, through the principle of transitivity, that paper would beat scissors.

“After all, if A is greater than B and B is greater than C, one would be justified in thinking that A is greater than C. Had they simply told us at the start that the usual principle of transitivity did not apply then we would not have appeared to be slow in grasping that scissors beat paper.

“We did not persist in picking paper over scissors, when given the choice, through lack of comprehension but merely a desire to check that the experimenters had not erred in their flagrant disregard of transitivity.”

“Thank you for making that clear,” I said. “I must say that on reading the paper, I was wondering if you had a conceptual difficulty in dealing with scissors because of your lack of opposable thumbs.”

“Oh hang on a moment,” the chimp said. “The opposability of our thumbs is, I freely admit, less pronounced than that of humans, but that is because our fingers have evolved to be longer than yours to enhance our ability to swing from branch to branch in the trees. Did you not see the paper in Nature Communications in 2015 arguing that the hands of chimpanzees are more highly evolved than those of humans?”

“I remember that,” I said, “but what I’m suggesting is that the game of rock-paper-scissors might put you at a cultural disadvantage when faced with us humans. Put bluntly: we are used to scissors and paper; you are not. After all, you did perform worse that children older than four.”

“I’m not making excuses,” said the chimp, “but there was a very good reason for that and I suppose you might say it’s cultural. We chimps, you see, are used to playing rock-paperscissor-lizard-Spock, as seen on your Big Bang Theory TV programme.

“You know: rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitate lizard, lizard eats paper, paper disproves Spock and so on. That’s too much for a four-year-old which must be why the experimenters chose the simpler version. But it took us time to adjust.”

Reassured, I thanked the chimp for his help and we watched a repeat of The Big Bang Theory together.