10. 2+2=tap tap tap tap

X was a horse in Germany, who was known to have been able to perform arithmetic and certain intellectual tasks. On being asked simple arithmetic questions, for example, the horse would be instructed to tap his foot to indicate the answer. The horse quickly became famous, and drew people in large numbers. This led the German government to appoint a commission, which, however, reported that no tricks were involved. Finally, in 1907, psychologist Y, after conducting many studies, determined that the horse did not actually perform the arithmetic itself, but would take cues from the expectations of the audience, even though the trainer was unaware that he was providing the cues. This anomalous research result is now called the X effect in honour of Y's study, and is an important theory in observer-expectancy effect and animal cognition.



ID X. (Brownie points for Y)

Answer:
X-Clever Hans
Y- Oscar Pfungst