In the late 1800s, a German high school mathematics instructor named Wilhelm Von Osten began parading around his horse, “Clever Hans”.
You see, Clever Hans was no ordinary horse. Clever Hans could add, subtract, multiply, divide, work with fractions, tell time, keep track of the calendar, differentiate musical tones, read, spell, and understand German.
Clever Hans would be asked a question and he would tap his hoof on the ground until he came to the right answer.
People came from all over to see Clever Hans give the answers to some very difficult math questions. But some folks were not impressed with Clever Hans. They thought that it was all some kind of trick.
The German board of education agreed and appointed a commission to investigate Hans.
Did Hans really add, subtract, multiply, divide, work with fractions, tell time, keep track of the calendar, differentiate musical tones, and read, spell, and understand German?
The quick answer…NO.
Hans did not know how to do any of the things that his owner claimed. Hans was not a mathematical
What they learned was that Hans was an expert at reading body language.
The investigators discovered that when a question was asked of Hans, he would start to tap his hoof until he came to the correct answer. He knew the correct answer by watching for cues given by the person asking the questions. The questioner’s posture and facial expressions changed in ways that were consistent with an increase in tension, which was released when the horse made the final, “correct” tap.
This provided a cue that Hans could use to know when to stop tapping.
In other words, Clever Hans was an expert at reading body language and knew when to stop tapping by the subtle cues given by the person asking Hans a question. Pretty interesting. Clever Hans really was clever, but not in the way that we thought.
Anyone that lives with a dog should know about this because this has lead to what is now called “The Clever Hans Effect.”
Social animals, like horses and dogs, become experts at reading our body language. This is important to understand when you live with a dog. Not too long ago I was working with a very nice couple that was having problems with their dog.