Clever Hans — The Horse That Could Count

Erik Brown
Apr 12, 2019 · 7 min read
Image for post
Image for post
Clever Hans Performing — Karl Krall [Public domain] / wikipedia commons

Many pet owners claim their loved animal is brilliant. Their skills vary from the mundane to the extrasensory.

Now, what if I told you that there was a historical case of a horse that could count and do various forms of arithmetic? The horse could also spell out answers, identify dates on a calendar, and recognize musical pieces.

However, there is a famous case of a horse that could count and do all the things I mentioned above.

The owner of the animal would have large exhibitions where the horse would answer verbal and written questions. The vast amount of times the horse’s answers were correct.

Attempts to prove that the abilities of the horse were a hoax, appeared to be easily foiled as well.

In 1904 the equine genius was even brought in front of the German Board Of Education, who studied him for a year and half and concluded there was no hoax.

But, could it possibly be true? Could a horse actually count and do math problems? How could a horse possibly recognize who composed a song? How could this be happening?

The answer is far more interesting than a mare doing math. It stretches into the realm of the consciousness of animals, psychology, and cognition. This particular horse also changed the way many experiments would be done in the future.

Hans the horse even has a methodology named him, which applies to modern experiments.

So, strap in and get ready as we go back to the early 1900’s for the story of Clever Hans — horse genius.

Introduction To The Four Legged Genius

Image for post
Image for post
Wilhelm Von Osten & Hans [Public domain] — Wikipedia Commons /

In the late 1800’s a German high school teacher, Wilhelm Von Osten, had a theory. He believed that animals had much more cognitive ability that humans gave them credit for.

In order to test this theory, he came up with an idea. He’d teach animals mathematics. He started out with a cat, which wasn’t a fan of math. His next pupil was a bear, who wasn’t a pleasant student. His next learner was an Arabian Stallion named Hans.

Now, Hans was an avid student. Osten was amazed when Hans learned to tap his foot three times when a 3 was written on a chalkboard. Osten obviously believed he struck gold with this one.

Math + Horse = Success

Osten seeing he had a brilliant student, came up with other things to teach the horse. He’d show the horse the alphabet, having the horse tap his foot once for A, twice for B, etc.

He’d also play famous musical scores for the horse and instruct the horse on who the composer was. Since the horse had a grip of the alphabet now, he could spell out the name of the composer when he heard a specific tune.

Osten would spend about 4 years instructing Hans, who appeared to understand and could amazingly answer questions by stamping a foot.

Towards the end of the training, Hans could even recognize paintings and stamp out the painters name.

Let’s Take This Show On The Road

“He possesses the ability to see sharply to distinguish mental impressions from each other, to retain them in his memory, and to utter them by his hoof language. Of course, not by himself has he learned all this, but by methodical instructions of a human intelligence…”

— Professor Moebius, zoologist referring to Hans

Now what do you do when you have the most brilliant animal in the world? You go to Las Vegas!

The horse became a sensation across Germany. By all accounts, it was an amazing show. Hans showed the mathematical abilities of a 14 year old and had an accuracy rate nearing 90%.

Osten had also put together incredible demonstrations of Hans’ abilities that baffled and amazed the crowd. By this time, Hans could even recognize colors and spell out their names. Hans could tell you the current time, recognize playing cards, and knew the calendar of the whole year.

If this wasn’t enough, Hans could also remember people pointed out in the crowd and spell their names at later times. He could also recognize people from pictures he was shown.

The crowds may have been amazed, but the scientific community was dubious. The halls of academia claimed it was a hoax. How could an animal be able to do this? It was impossible. Osten was a fraud!

There was one issue that also baffled Osten’s accusers though. Osten gave no signs to the horse when questions were asked that would tip Hans off. In fact, Osten didn’t have to be present for Hans to give the correct answers. Others could ask the horse questions and he still gave the right answers as a 1911 article in the New York Times reported.

The Clever Hans Commission

Image for post
Image for post
Clever Hans tapping out answers. (Karl Krall / Wikimedia Commons)

The scientific community would get to the bottom of Hans’ abilities. The German Board of education put a commission together — The Hans Commission. This group was made up of zoologists, a psychologist, animal trainers, school teachers, and a circus manager. They tested the horse for a year and half and couldn’t find any instance of fraud.

Although, they couldn’t find fraud, they weren’t totally sold on the genius nature of the horse.

After testing the horse, Pfungst noticed something, Hans missed answers where the questioner didn’t know the solution. The professor tried something else, he blocked Hans from seeing the face of the questioner. Hans started answering questions incorrectly.

Pfungst started to see a crack in a wall. The horse wasn’t brilliant, but nonetheless had a brilliant ability.

Hans was able to read minute details in the face of the questioner to come to a correct answer within milliseconds. Let’s examine this. Let’s say you asked the horse, “What’s the square root of 16?” The horse would begin to tap his foot, examining your face as he did. When he got near four taps, he’d begin to notice a change on your facial or body expression, then stop at four.

Is it a trick? Yes it is, but an absolutely brilliant trick. Remember, Hans was being asked times, dates, colors, and spelling out peoples’ names. Hans’ abilities were so amazing Osten didn’t even realize what was happening.

Pfungst was able to recreate the “Clever Hans Phenomenon” in a series of experiments where the professor played the role of Hans. He’d have examiners ask him questions mentally and answer by only responding to facial features of the questioner.

In future animal experiments, other scientists would find more examples of this “Clever Hans Phenomenon” and come to a conclusion that animal experiments must be done more carefully in regards to face to face contact. In fact, a paper published in 2013 in Communicative & IngrativeBiology revisits recent examples of this phenomenon seen in current experiments with parrots, dogs, and dolphins.

The Fate of Hans

Image for post
Image for post
Hans & Osten — picture from the public “I”

After Pfungst’s experiments proved Hans wasn’t a genius, the horse’s popularity waned a bit. The magic of his ability was gone.

However in reviewing the case, perhaps Wilhelm Von Osten did prove his original point. Osten wanted to prove that animals had much more cognitive abilities than humans gave them credit for.

His horse managed to fool many members of the scientific community. Hans was also able to convince large crowds in Germany of his brilliance. The horse did this by reading involuntary signals sent by the humans who questioned him.

Hans may not have understood math, but he demonstrated an incredible unperceived ability that humans originally couldn’t understand.

Osten may have done it unknowingly, but he did technically prove that this particular animal did have cognitive abilities humans couldn’t imagine.

Now, what happened to our brilliant four-legged friend? Unfortunately, Hans was subject to fate much like his two-legged questioners. Despite being a horse, Hans couldn’t avoid the draft.

World War I started in 1914 and humans and horses were called to fight for Germany. According to the Animals In War Memorial Fund, 8 million horses would go on to die in the fighting during WWI. Hans was one of that number, dying in 1916.

However, he is still remembered over a hundred years later for his ability to learn a lesson that wasn’t being taught. Humans of today spend countless hours working on their skills of observation and being present in the moment. However, they’re novices compared to this horse. Hans was such a master of those skills he could foul countless “intelligent” humans who examined and questioned him.

Thank you for reading my ramblings, if you’ve enjoyed what you’ve read please share. By the way, the theme song for Mr. Ed has been stuck in my mind the whole time I’ve been writing this article.

Lessons from History

Lessons from History is a platform for writers who share…

Sign up for Lessons from History

By Lessons from History

Lessons from History is a platform for writers who share ideas and inspirational stories from world history.  Take a look.

By signing up, you will create a Medium account if you don’t already have one. Review our Privacy Policy for more information about our privacy practices.

Check your inbox
Medium sent you an email at to complete your subscription.

Erik Brown

Written by

Work out fanatic, martial artist, student, MBA, and connoisseur of useless information.

Lessons from History

Lessons from History is a platform for writers who share ideas and inspirational stories from world history. The objective is to promote history on Medium and demonstrate the value of historical writing.

Erik Brown

Written by

Work out fanatic, martial artist, student, MBA, and connoisseur of useless information.

Lessons from History

Lessons from History is a platform for writers who share ideas and inspirational stories from world history. The objective is to promote history on Medium and demonstrate the value of historical writing.

Medium is an open platform where 170 million readers come to find insightful and dynamic thinking. Here, expert and undiscovered voices alike dive into the heart of any topic and bring new ideas to the surface. Learn more

Follow the writers, publications, and topics that matter to you, and you’ll see them on your homepage and in your inbox. Explore

If you have a story to tell, knowledge to share, or a perspective to offer — welcome home. It’s easy and free to post your thinking on any topic. Write on Medium

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store