Clever Hans: The Horse That Knew Everything (Sort Of)

In 1904, a nine-year-old horse called Hans trotted through performance halls in Berlin astounding crowds with his uncanny mental agility. His owner, Herr Wilhelm von Osten, was a former schoolteacher and educated his horse to the level of a child the same age. Or so he claimed. The Orloff stallion learned to spell, do math, recognize people from photographs, differentiate between colors and music, and answer various questions. All Hans had to do was tap his right front hoof once to denote one, twice for two, and so forth. Letters were signified in the same manner, one tap corresponding to A, two taps to B. Hopefully Hans wasn’t asked to spell too many words with the letters Y and Z.

Von Osten’s horse also boasted an elephant-like memory. In one demonstration, Hans was introduced to a Count Dohna. He was told, “That is Count Dohna.” Thirty minutes later the Count was pointed to and von Osten asked Hans his name. The horse walked up to a blackboard filled with the letters of the alphabet and picked out D-o-h-n-a. Another stunt involved members of the audience who would offer the stallion photos of themselves, then line up in front of him. Von Osten would show Hans a photo and have him point out that person in the line. This proved as easy for the horse as for any person.

Clever Hans

Clever Hans with von Osten

Clever Hans dazzled audiences and puzzled scientists. Brilliant minds studied the horse, trying to learn whether it was all a trick or if the horse was in fact educated. The most obvious test was to learn if Hans could still perform without von Osten present. According to one article, the answer was yes: “It is understood that the animal has answered questions and figured arithmetical sums when his instructor has not been near.”

The skilled stallion even managed to cause a political rift in Prussia. One of Hans’ enthusiastic fans happened to be the Prussian Minister of Education, Dr. Studt. Studt was so taken by the animal that he wished to have him perform before Emperor William. However, the other ministers objected. Frustrated by the opposition, Studt threatened to resign from his position, but eventually came to his senses and stayed with the Ministry. Otherwise, this could have been the first horse to cause a split in a government.

Hans became an international sensation. In an article about talented circus horses, one American journalist said of Hans: “Berlin, however, has an animal of the species now on show which has gone beyond precedent in cultivation and exhibits phenomena of cerebration out of all parallels.” Dr. William T. Hornaday, Director of the Bronx Park Zoological Gardens, was equally impressed. In his 1922 book, The Mind and Manners of Wild Animals, he wrote that Hans “was a phenomenon, and I doubt whether this world ever sees his like again. His mastery of figures alone, no matter how it was wrought, was enough to make any animal or trainer illustrious.”

Even The New York Times was caught up in the Hans hype. There was hope and expectation that the horse’s education would advance to the point where he would actually learn to speak—becoming a true Mister Ed. The Times writer said of Hans’ potential for language:

“[Hans] has not got so far as that yet, but is well on toward it, and before the cold weather sets in may be able to hold discourse with his beleaguering professors in some dialect that both can understand. It would be mortifying to discover that its kind still kept so poor an opinion of us as that held by Swift’s cultivated and conversible houynhnhms. But considering that the most pretentious of our species cut their tails and manes off for fashion’s sake and torture them in various ways to promote attitudes and motions of style, while the brute of our species heaps on them all manner of cruelty and ill, it would not be at all surprising if they did so.”

He had a point, if horses could talk, they would justifiably have a lot of complaints.

Science, however, was not about to accept that a horse could possess the intelligence of a small child. Several German scientists were determined to expose some form of trickery. Ultimately, the director of the “Psychological Institute” of the Berlin University, Professor Oskar Pfungst concluded that Hans only knew the answer if the person asking the question knew the answer. In studying the horse, Pfungst confirmed that it could answer questions without von Osten present. Hans was able to answer whatever Pfungst asked. Still, a horse could not possibly possess this sort of intelligence. Rather, Pfungst realized the horse had a remarkable ability to perceive signals from the questioner, despite his efforts to remain still. Hans was detecting sign whether they were conscious or unconscious. When Pfungst asked a question, he recognized, his head would nod ever so slightly to watch Hans’ hoof. That was the subject’s cue to start tapping. When he tapped an appropriate number, Pfungst would lift his head, satisfied with a correct answer. Again, the subtle movement was picked up by the horse. Anyone wishing to ask Hans a question would likely be expecting a correct answer, and therefore would be an excellent candidate to give strong signals. Pfungst tested his theory further by asking Hans questions from greater and greater distances. The farther away he stood, the more difficult it was for the horse to pick up the signals. Blindfolded, Hans’ brainpower was reduced to that of any other horse.

Pfungst’s experiments with Hans ruined his reputation and put an end to von Osten’s success. Suddenly, the public no longer saw Hans as an intelligent horse. People felt duped, even though the horse still displayed extraordinary talent worth the price of admission. Though it seems hard to believe a horse could read movements and human expressions with such accuracy, Pfungst’s theory was agreed upon by another prominent Berlin mind, Dr. Albert Moll. Moll was neurologist, a founder of the Berlin Society of Psychology and Characterology, and author of the 1889 book, Hypnotism. Moll believed that hypnotism allowed subjects to respond to extremely subtle signs. “Signs that are imperceptible to others,” he said, “are nevertheless perceived by a subject trained to do so, no matter whether that subject be a human being or an animal.” Despite proving Hans was not an intelligent horse, Pfungst cashed in on the horse’s talent with his book entitled The Intelligent Hans.

While all these great minds focused their energies to prove they were smarter than a horse, author Ricky Jay references a scholar who figured out the method three hundred years earlier. In Learned Pigs and Fireproof Women, Jay writes of Sa. Rid’s book, The Art of Juggling or Legerdermaine, which claimed “…nothing can be done [by the horse] but his master must first know, and then by his master knowing, the horse is ruled by signes.”

Von Osten passed away on June 29, 1909 at the age of 70. Hans was bequeathed to Karl Krall, a wealthy goldsmith and an amateur parapsychologist of Elberfeld. Krall took Hans in and educated several horses of his own – two Arab stallions, Muhamed and Zarif, a Shetland pony called Hanschen, and an older black stallion, Berto. Krall even experimented with the mind of a young elephant, Kama. His exhibition of horses came to end with the outbreak of the World War I. The horses were forced to leave the stage and enter the battlefield.

© Marc Hartzman


Raining Cats and Dogs — and Frogs

In times of torrential rain, it is quite probable that some feeble-minded fellow or garrulous gentleman searching for small talk will express its volume in terms of cats and dogs. However, such foolish and juvenile hyperbole opens the window to discuss a slimier, jumpier creature that has in fact fallen from the skies. The frog, by several accounts, has in fact rained upon land.

The most recent case of frog rain was in 2005, when thousands of the web-footed creatures descended upon on a Serbian village. Fearful residents thought the world was coming to an end.

Science, however, reared its rational head and offered a more suitable explanation: a whirlwind had simply sucked up the frogs from a nearby body of water and carried them toward the village where they finally fell to the ground.

The frogs occasionally survive such storms. Serbian witnesses said the little amphibians looked startled at first, then returned to their normal behavior. Just like the poor people they landed on.

In July of 1901, Minneapolis, Minnesota, suffered a frog downpour. A newspaper reported: “When the storm was at its highest… there appeared as if descending directly from the sky a huge green mass. Then followed a peculiar patter, unlike that of rain or hail. When the storm abated the people found, three inches deep and covering an area of more than four blocks, a collection of a most striking variety of frogs… so thick in some places [that] travel was impossible.”

Whirlwinds are powerful enough to pick up other creatures as well. London received a frog shower in 1998. And in 2004, it rained fish in Wales. Two years later India also got a fish shower.

In 1989, a light shower in Ipswich, Australia sprinkled about 800 sardines on a couple’s front lawn.
Worms and squid have also been scooped up and dropped onto unsuspecting homes. But cats and dogs? Nonsense.

© Marc Hartzman

Don the Talking Dog

Those fond of clichés will surely agree that if a dog is man’s best friend, a talking dog might be man’s BFF. In the early 1900s, a dark brown setter, called Don the Talking Dog, was such pal. The pooch belonged to a German gamekeeper named Martin Ebers, who lived in a quaint Western Germany village called Theerhutte, near Hamburg. But his voice attracted the world’s ear.

News of Don came in 1910, after an American newspaper article claiming Alexander Graham Bell had trained his terrier to speak. Germans didn’t think much of the article — at the time there was a belief that anything was possible in America. But rather than let America have the glory of a talking dog, Ebers’ nephew brought media attention to his uncle’s wondrous companion. Suddenly, the small village was bustling with curiosity seekers and reporters wishing to see if Ebers’ dog was the real deal.

Even skeptics became believers after meeting Don. In describing a conversation with the dog, one newspaper claimed, “The tone was not a bark or growl, but distinct speech.” Another correspondent wrote, “The dog is an unqualified scientific marvel.”

Don reportedly began speaking on his own accord in 1905, at the age of six months. As one might expect with a dog, his first words were in regard to food. While the family was eating dinner one evening, Don, like any dog, waited beside the table begging for scraps. His master asked if he wanted something, and Don responded “Haben! Haben!” (Want! Want!). Ebers asked the question again, disbelieving his own ears. Sure enough, Don said “Haben! Haben!”

The dog’s vocabulary soon expanded to other areas in the food department with “hunger” and “kuchen” (cakes). He also pronounced “ja” (yes) and “nein” (no), allowing Don to express his feelings, such as a dislike for cold, wet weather. The clever canine even learned to form a rudimentary sentence with his small arsenal of words. If asked how he was doing, Don could have responded, “Hunger, want cakes.”

The four-legged phenomenon soon attracted the attention of Karl Hagenbeck, the famed German animal trainer and circus founder, as well as other circus showmen and music hall managers. Hagenbeck offered Ebers $2,500 to exhibit Don in his outdoor menagerie at Hamburg. Another impresario offered Ebers $15,000 to purchase the extraordinary dog.

While showmen and the general public were enamored with Don, psychologist Oskar Pfungst was not. In 1912, having debunked an educated horse called Clever Hans several years earlier, Pfungst took it upon himself to explain Don’s garrulous nature. He visited Don and recorded his “speech” on a phonograph. He concluded that the dog merely responded to questions with noises the way any dog might, but through the power of suggestion, listeners heard what they were expecting to hear. A similar experience occurred in more recent years with a dog crooning “I love you” on a David Letterman Stupid Pet Tricks segment. And on YouTube, more than 8,000 videos can be found on dogs allegedly professing their love.

Upon hearing of Pfungt’s findings, The New York Evening Post reported: “It begins to look as if there really were a rather sharp limit to animal intelligence.” As with Hans, Pfungst once again burst an optimistic society’s bubble.

© Marc Hartzman

Russian Two-Headed Dogs

If you were the child of Dr. Vladimir Demikhov, a Russian scientist who gained fame in the 1940s and ’50s, a two-headed dog could very well have eaten your homework.

Over the course of 20 years, the controversial Demikhov created at least 20 two-headed animals in his quest to perfect the art of transplantation. Although he sounds like a modern-day Dr. Frankenstein, Demikhov’s work was an attempt to understand how damaged organs can be replaced, or how to create artificial substitutes. His studies would eventually set the stage for similar organ transplants some forty years later.

Demikhov’s early work focused on replacing hearts in dogs with artificial blood pumps, but by 1946 he successfully transplanted a second natural heart in a dog. He simply removed part of a lung to clear some space for the extra ticker, which beat independently of the original heart. Some of the two-hearted dogs managed to live up to five months. The ever-curious surgeon carried on his work by experimenting with just how much work a single heart could do. So rather than add a second heart to a dog, he added a second front end of a pup. This would determine if one heart could pump enough blood for both heads.

Demikhov had a breakthrough with a German Shepherd called Pirat. Pirat lasted 30 days with the front end of a puppy attached to him. The puppy’s head was attached by joining major blood vessels. “The big dog doesn’t understand,” the scientist told a visiting reporter. “He feels some kind of inconvenience, but he doesn’t know what it is. Sometimes the puppy will playfully bite the ear of the big dog and Pirat will shake his head but he never has tried to scratch or kick off the extra head.”

A Russian Two-Headed Dog

An example of Dr. Demikhov’s experiments. His curious face is seen in the upper left corner.

Both heads slept and woke independently, which was a breakthrough for Demikhov because it proved that the head could be attached and retain some level of normalcy. Of course, “normalcy” is all relative. The puppy didn’t need to eat or drink, as it gained all its nourishment from Pirat. In fact, when it did drink, the water went down its throat and out onto the Shepherd’s neck.

After a month of astounding scientists and anyone else who happened to see the two-headed on its regular walks, Pirat developed edema, a condition in which lymphatic fluid infiltrates into connective tissue. Demikhov was forced to perform another surgery to amputate the puppy head. Pirat was returned to normal — or at least as normal as a dog could be after gaining and losing a head.

© Marc Hartzman

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