An interesting occurrence in the field of animal cognition that received plenty of observational evidence but no scientific approval. A famous case was that of Clever Hans, a horse that demonstrated to audiences many times that he could add, subtract, and even solve complicated mathematical problems by tapping out numbers with his hoof and stopping when he had reached the correct answer. The horse\u2019s trainer, retired German schoolteacher Wilhelm Von Osten, was not a trickster and sincerely believed that his horse was doing this unaided. But when the case was investigated by psychologist Oskar Pfungst, it was revealed that Von Osten and others who were brought in to ask the animal questions, would involuntarily jerk their heads when Clever Hans had tapped out the right answer. In this way the horse was cued. Further investigation discovered that Clever Hans was able to detect human head movements of one-fifth of a millimeter.<\/p>\n
Information about the investigation of Clever Hans was published in 1911 and, according to the science writer Martin Gardner, by 1937 there were more than 70 thinking animals making a living on the stage or circus for their owners. As well as horses there were cats, dogs, pigs, a dolphin, and two learned London geese.<\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
An interesting occurrence in the field of animal cognition that received plenty of observational evidence but no scientific approval. A famous case was that of Clever Hans, a horse that demonstrated to audiences many times that he could add, subtract, and even solve complicated mathematical problems by tapping out numbers with his hoof and stopping […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-210596","post","type-post","status-publish","format-standard","hentry","category-c"],"yoast_head":"\n