Clever Hans, who lived between 1895-1916, became a world-famous horse and became famous for his ability to perform mathematical operations. In terms of breed, Clever Hans is a horse breed known as Orlov or Orlov Trotter and is a horse breed known for its superior speed and intelligence.
The Orlov Trotter is a horse breed with a hereditary fast trot, noted for its outstanding speed and stamina. It is the most famous Russian horse.
Clever Hans, whose German name is der Kluge Hans, was the horse of Wilhelm Von Osten, a mathematics teacher and amateur horse caretaker in Germany, and in a sense, it became a student.
Clever Hans (1907) was a horse that was claimed to have performed arithmetic and other intellectual tasks. After a formal investigation in 1907, psychologist Oskar Pfungst demonstrated that the horse was not actually performing these mental tasks, but was watching the reactions of his trainer.
While the Clever Hans became the most famous animal of the 19th century, its fame spread around the world and it was observed that it played various intelligence games. Hans, who was taught addition, subtraction, division, and multiplication by Osten, who sometimes prepared written questions and sometimes verbally, stamped its foot on the ground as much as the number of correct answers in response to these. For example, 3+4=? It answered the question by tapping its foot on the ground 7 times and stopping. Osten, the owner of Clever Hans, has taken his horse to many countries and displayed its intelligence, free of charge.
Carl Stumpf (21 April 1848 – 25 December 1936) was a German philosopher, psychologist and musicologist. He is noted for founding the Berlin School of Experimental Psychology.
Clever Hans, who was featured in the New York Times in 1904 with its talents, also attracted the attention of scientists. A commission consisting of 13 people, called the Hans Commission, examined the horse; determined that there was no cheating.
While the psychologist and biologist Oskar Pfungst was responsible for the research - later - Hans answered the questions correctly when someone else asked them and proved that the owner Von Osten was not a fraud.
Oskar Pfungst (21 April 1874 – 14 August 1932) was a German comparative biologist and psychologist. While working as a volunteer assistant in the laboratory of Carl Stumpf in Berlin, Pfungst was asked to investigate the horse known as Clever Hans, who could apparently solve a wide array of arithmetic problems set to it by its owner.
However, the clever horse could not give the correct answer when it could not see the face of the person asking the question. Pfungst, who conducted the research, deduced the following from this situation: The smart horse takes into account the facial expressions of the person asking the question. By reading a person's face, it determines whether its answer is correct or not.
Psychologist Pfungst called this the "Clever Hans Effect". While it has been proven that animals can recognize signals and signs that humans have difficulty in identifying, this situation has been referred to as the Clever Hans Effect in the literature. Thanks to the Clever Hans Effect, many experimental methods in psychology and ethology (the branch that studies animal behavior) have changed and it was believed that it would be possible to obtain reliable results on animal behavior without the Clever Hans Effect.
This effect, which is vital in research on animal cognition, has proven that animals can receive signals from them even if people are not aware of it, and it has been stated that the performance evaluation of animals should be made accordingly.