Can Animals Do Mental Arithmetic?

Counting Horse
Clever Hans the Counting Horse
Can Animals Do Mental Arithmetic? Clever Hans was a famous horse who astonished people by his ability to add, subtract, multiply and divide numbers. 56 divided by 7 was easy. Fractions were no problem. He could also read and spell. Asked to solve a problem, he would stamp a hoof in reply and was always correct. But scientists proved he was responding to subliminal cues from his trainer who, like everyone else, was unaware of them. Clever Hans teaches us an important lesson about human-animal relations: don’t attribute to animals characteristics they don’t possess!