Horse Sense: Clever Hans and the Crepuscule of Equine Telepathy
Hinternet Summer School Projects | MH Rowe
1.
In the fall of 1900, a man who had traveled to Russia from his home in Berlin bought at auction a magnificent trotting horse named Hans: a common enough occurrence at the time, to buy a strapping horse. This particular buyer was Wilhelm von Osten. He had retired not long before from a career as a teacher of mathematics to the browbeaten youth of his neighborhood. Now he spent his days shooting birds on his long walks in the countryside beyond Berlin, and nursing, at all times, eccentric ideas about animals, in particular horses and dogs.
Called both generous and tyrannical on account of the severe sway in his moods, von Osten cultivated an interest in phrenology as well. He liked orderly procedure. He considered himself an expert on the “landscape” of animal skulls and the relationship between cranial shape and intelligence. The psychologist Oskar Pfungst later described von Osten as “a man between sixty and seventy years of age, his white head covered at all times with a black, slouch hat.”1 The older man perhaps wished to conceal from view the shape of his own skull.2
The new horse was presumed to be a Russian stallion. Von Osten later went to considerable lengths to establish the horse’s genealogy. He insulted a prominent and much-traveled Balkan horse dealer, calling the man a “grousing pig, fondling his ledgers” in a long and severe letter, in which he also insisted on receiving much more information than any provincial horse trader could reasonably be expected to supply from out of the bureaucratic depths of the outer Austro-Hungarian Empire.3
Traveling by train, von Osten harassed horsemen and their patient wives, always returning to Berlin none the wiser. He grew to suspect that his animal was of Austrian origin, for no other reason than he felt some growing antipathy toward Russia, perhaps as a result of the Franco-Russian alliance that formed after Bismarck’s decline and dismissal in 1890.
Efforts to trace the genealogy of Hans the horse were not successful. “[Hans] wanted me to know where he comes from, as if it is so distant he is still shocked to have come this far,” von Osten later remarked.4
By the spring of 1901, von Osten appeared in public, exhibiting his horse, whom he had newly nicknamed Kluger Hans — Clever Hans. The feats of Clever Hans drew almost instant acclaim and debate, as if the creature truly had descended into human company out of some Olympian zoo, if not palace. Von Osten had found his super-intelligent horse. The creature had mesmeric equine eyes and a steady gaze to match.
Newspapers celebrated and disparaged Clever Hans. Scientists from far and wide wrote articles about him. Soon skeptics and believers alike crowded von Osten’s courtyard to see the horse at work.
The psychological researcher Oskar Pfungst, an assistant of the illustrious psychologist and philosopher Carl Stumpf, was soon called upon to investigate the abilities of this horse endowed with an ability for “conceptual thinking”. In his book Clever Hans, Pfungst provides an excellent precis of the various feats of calculation and communication that von Osten appeared able to cause the animal to perform. Readers will note that Hans’s responses to human questions were given as answers by repeated taps of his hoof on the ground, or by ducking, nodding, or swaying his head. Von Osten also devised a chart that translated the letters of the alphabet (and certain clusters of letters, as well as phrases) into numbers of taps, which the horse could reproduce painstakingly to spell words. As Pfungst recounts:
[Hans] had, apparently, completely mastered the cardinal numbers from 1 to 100 and the ordinals to 10, at least. Upon request he would count objects of all sorts, the persons present, even to distinctions of sex. Then hats, umbrellas, and eyeglasses. Even the mechanical activity of tapping seemed to reveal a measure of intelligence. Small numbers were given with a slow tapping of the right foot. With larger numbers he would increase his speed and would often tap very rapidly right from the start, so that one might have gained the impression that knowing that he had a large number to tap, he desired to hasten the monotonous activity.5
There is no boredom like the boredom of a horse aware that he is the subject of tedious experimentation. Hans was asked to do arithmetic. He was asked to identify the subjects of paintings — Horse, he answered correctly when asked, rather unimaginatively, to name the creature in a watercolor. On one occasion he tapped out consecutively 58 numbers to indicate the sentence, Brücke und Weg sind vom Feinde besetzt (“The bridge and the road are held by the enemy”), which he memorized the day before.6 His training seems to have taken on a military edge.
Pfungst relished the horse’s attitude, even his apparent wit. Observing Clever Hans’s reaction to music, for example, Pfungst noted that “when the seventh chord, D-F-A-C, was sounded, [Hans] shook his head disapprovingly. He evidently was old-fashioned in his musical tastes and not agreeably disposed toward modern music.”7 Anyone who has put on a record of ambient electronic compositions with a cat in the room may have noticed a similar expressive distaste. But consider Clever Hans’s point of view: forced to tap out endless numbers to spell even medium-length words, only then to be subjected to the avant-garde. One imagines this is hardly an ideal afternoon for any but the most patient and disciplined creature.
In the end, Pfungst’s report devastated Wilhelm von Osten. The examinations, carried out in an open courtyard, drew small crowds, but the experiments themselves were carefully constructed. Pfungst was imperturbable and orderly in the face of von Osten’s willfulness. He had concocted the tests for maximum objective measurement. His hypothesis was that either Clever Hans was truly clever, or he was reading signals from his questioners.
As mathematical questions were put to the horse, Pfungst varied the conditions. Sometimes the questioner was visible to the horse, sometimes not. Sometimes the questioner knew the answer to the question asked, sometimes not. In the end, Pfungst reported that he could not deny the horse’s abilities but that these abilities were not as they appeared to be. Rather than intelligent calculation, the horse displayed an acute capacity to indicate the correct answer —that is, to tap his hoof the correct number of times— based on the unconscious body language of the person making the inquiry. Clever, yes. Intelligent, perhaps not.
The letters of Carl Stumpf reveal that no less an eminence than Sigmund Freud attended one of these trials. (Stumpf and Freud were connected professionally; both had been students of Franz Brentano.) Stumpf records no comment from the Viennese doctor. Apparently, Freud stood impatiently “among the distinguished and undistinguished at the edge of the courtyard.”8 Pfungst later commented to Stumpf that Freud observed “impassively from the stones, so that the blinders of the horse kept him quite invisible.”9 Perhaps the psyche of a conventional horse was just as vulnerable as any straitlaced bourgeois gentleman to the unsettling revelations of psychoanalysis. Such gentlemen usually have different sorts of blinders, or so Freud thought.
Freud’s appearance adds an uncanny nuance to another of Stumpf’s observations. Some time after the publication of Pfungst’s book, Stumpf wrote to him and cited a passage on the minds of horses from Charles Darwin, who in his Expression of the Emotions in Man and Animals of 1872 can be found reflecting on horse habits as follows:
That some physical change is produced in the nerve-cells or nerves which are habitually used can hardly be doubted, for otherwise it is impossible to understand how the tendency to certain acquired movements is inherited. That they are inherited we see with horses in certain transmitted paces, such as cantering and ambling, which are not natural to them,—in the pointing of young pointers and the setting of young setters—in the peculiar manner of flight of certain breeds of the pigeon, &c.10
This image of genetically inherited habits later informed Freud’s later theory of the human ego. Thus he writes in The Ego and the Id (1923):
The experiences of the ego seem at first to be lost for inheritance; but, when they have been repeated often enough and with sufficient strength in many individuals in successive generations, they transform themselves, so to say, into experiences of the id, the impressions of which are preserved by heredity. Thus in the id, which is capable of being inherited, are harboured [sic] residues of the existences of countless egos; and, when the ego forms its super-ego out of the id, it may perhaps only be reviving shapes of former egos and be bringing them to resurrection.11
The id is a horse, the ego too. Every personality is a Trojan Horse. But what “countless egos” were being stored up in Clever Hans? What moves? What memories and impressions, ideas and impulses? How was the horse formed or deformed?
2.
*Now we move into the ghostly years. For Clever Hans haunted the world long before his mysterious death.
Wilhelm von Osten, the eccentric in his black slouch hat, died in disappointment in 1909, a few years after Pfungst published his book. A deep skepticism now reigned regarding the horse. No matter von Osten’s convictions, Pfungst’s tests yielded conclusions that were beyond the irascible horseman’s ability to contradict. In his will, however, von Osten bequeathed Clever Hans to an industrious true believer, a man named Karl Krall.
A wealthy manufacturer and vigorous man, Krall’s family had initially grown rich from a successful jewelry business. If he lacked von Osten’s eccentricity, Krall matched almost exactly his predecessor’s obsessive dedication to demonstrating the intelligence of his horse.12
On his land Krall built a large barn for Clever Hans and two others, Mohammed and Zarif. Collectively they were known as the “Elberfeld horses”. Krall trained all his animals, including an elephant who proved to be a disappointment, intellectually speaking, to communicate and perform mathematical feats of calculation. The horse Mohammed proved to be his star pupil, outshining even the veteran Hans.
Hans in fact recedes a bit into the background during the Elberfeld period. The Belgian writer, Maurice Maeterlinck, who visited Krall and Hans sometime in 1913, attributes Hans’s demotion in part to the stallion’s exposure, for perhaps the first time in many years, to the presence of a mare. Such disturbance of sex may or may not be a sign of intellect. In an overexcited and less clever moment, Hans scraped himself open on a rail in the barn at the sight of a pony named Rosa. Krall and his men subsequently had to “force back [Hans’s] intestines and sew up his belly.”13 From that point on, Hans was allowed time away from the tedium of arithmetic and the calculation of square roots.
Maeterlinck’s account of Hans and Krall is amusing and sensitive. As a thinker the Belgian may be more open than great, but he cultivates a mysticism suitable to the destiny of Clever Hans.
Addressing the work of Oskar Pfungst, Maeterlinck shows no patience. He calls the man a pedant. Krall, he says as a point of comparison, is marvelous and imaginative. Maeterlinck’s own investigation into the question of horse intelligence can nevertheless appear a bit ludicrous at first glance. Asked by Krall to suggest a number for which Muhamed can calculate the square root, Maeterlinck all but panics. He confesses absurdly and touchingly that he has “not the faintest idea of the mysteries concealed within these recondite and complicated operations.”14
When he finally provides a figure, Muhamed seems unable to solve the question. Krall turns in amusement to Maeterlinck and asks him whether the figure does indeed have an exact square root. When he confirms the number does not, Krall concludes that the horse will not answer unless there is a precise solution. The playful Muhamed then gets excited and “catches his good master by the seat of his trousers, into which he plants his disrespectful teeth.”15
Soon enough, Maeterlinck returns to old Clever Hans, visiting the horse in his large stall. The stitches have healed. Hans tosses his head back and forth, a brief frisk of his mane. The scene resembles a visit to an aged patriarch on his sickbed. Hans, however, is not sick. A strange strength is growing in him.
Maeterlinck waxes philosophical on this visit. He raises and dismisses the question of “telepathy” as too narrow for the explanation that best fits the evidence, for Krall has been able to show again and again experimental results that seem to contradict Pfungst’s data. Clever Hans and Muhamed show themselves to be excellent and almost automatic calculators. They calculate answers regardless of whether the questioner knows the answer or not. Some sort of instinct is at work, although Maeterlinck cautions that “we have given the name of instinct to that which we could not apprehend.”16 He considers the possibility that “mediumistic or subliminal theory” explains the abilities of Clever Hans.17
Gazing at Hans, the writer recalls human mathematical prodigies, “lightning calculators”, who have an intuition that allows them to perform superhuman feats of calculation but without a real understanding or ability to explain what they are doing. They simply do it, calculating vast sums in an instant. Maeterlinck believes those human individuals are like the Elberfeld horses.
In the stall in his barn, Hans fixes Maeterlinck with an especially intense gaze. The writer goes on for pages, elegantly describing the “subliminal being” of the horse that possesses “a psychic power similar to that which is hidden beneath the veil of our reason and which, as we learn to know it, astonishes, surpasses and dominates our reason more and more.”18 The essence of the subliminal is that it pervades all things. It may even constitute the dimly grasped essence of the cosmos.
Hans continues to gaze at Maurice Maeterlinck now. Something clouds but opens the horse’s eye. Only a few pages before, Maeterlinck had asserted the superiority of “subliminal being” in a horse like Clever Hans, “because [the horse’s subliminal sense] is not incessantly attacked, coerced and humiliated by the intelligence which gnaws at it, stifles it, cloaks it and relegates it to a dark corner which neither light nor air can penetrate.”19
Human intelligence and reason block the sense of the subliminal. To be more precise, reason intervenes and obstructs the successful transmission of subliminal intuition, except, for example, in the case of those mathematical prodigies who can accomplish impossible calculation without really engaging their intellect. The subliminal and the mathematical —perhaps even the unknown future— exist on a plane outside and beyond intellection.
As Édouard Claparède said of the Elberfeld horses, “The intellect appears only as a makeshift, an instrument that betrays that the organism is not adapted to its environment, a mode of expression which reveals a state of impotence.”20 No rationalizing intellect can match the mind of a superior being like Clever Hans. The horse is directly connected to the essence of the universe, a being of intuitive genius beyond the hesitant and dull plodding of human thought. Yet the subliminal horse is no cold machine; it is playful and full of feeling.
A remarkable thing happened on one of Maeterlinck’s many visits to Clever Hans’s stall. Maeterlinck, having turned his eyes on the horse, noticed that this time he not only looked, but was looked at in turn. He quailed at the attention. Maeterlinck knew that Hans had grown older, and perhaps the horse knew it, too. The wound no longer dripped; the horse was not ill. But what agony is there in the gaze of this powerful survivor of human attention? “His fate is now being decided,” Maeterlinck writes, looking at Clever Hans, “and his eye, melting with anguish, devours my mind.”21
An alien intelligence in the horse, the subliminal intuition of Hans, overwhelms Maeterlinck. The human being assumes at first that the animal appeals to a master for some decision about his equine fate, but the desire and will of the horse swamp the mind of the mystic. This is the moment toward which our story has been tending all along. “The only important thing to observe,” Maeterlinck writes, “is that at one time it is man who transmits his terror, his perception or his idea of the invisible to the animal and at another the animal which transmits its sensations to man.”22 At last a man has truly met Clever Hans, the transmitter of subliminal capacities.
The next day, Maeterlinck was forced to depart Elberfeld. The experience shook him, and he promised to return. Krall promised as well to inform him about the health of Hans and Muhamed in particular.
But there would be no reunion. Less than a year later, the war came. Europe descended into fire, smoke, and misery.
Maeterlinck was never told, but in 1916, desperate for all the implements of war —World War I was the last major conflict in which horses played a large and decisive part—, a detachment from the German army came through Elberfeld. A major identified in Krall’s letters as Ravensfelker conscripted all of Krall’s horses. Clever Hans went to the front.23
3.
The final years, if they truly are the final years, are almost a complete mystery. Later evidence that Clever Hans was not drafted into military service has been shown to be a bookkeeping error. But following the trail suggested by the meager crumb left by Ravensfelker sends us into an archival maelstrom. In the swirling eye of this mass of military paperwork one can find only here and there other clues swept improbably into the path.
Though the name “Hans” does not appear in any military ledger, annotations regarding an aged Russian stallion do recur in suggestive order, starting in Elberfeld. My only real contribution to scholarship might be that I have found the letters of one Adalfuns Schaum, an enlisted man under the command of Oberst Ulrich Zürn in late 1917. The detachment Zürn commanded possessed several horses, as did many similar artillery units, and they endured periodic delay in food re-supply after bitter campaigns late in the fall of that year. Like many in the German army, their hopes of victory were dwindling to desperation. Some had already begun to shoot and eat their horses.
The relevant passages from the letters of Adalfuns Schaum may be cited in full:
The Oberst has his little moods. He is always angry. He is always proud. Battle never suited him, it’s all logistics, which is servant work. This morning he was told that the truck, which he thought full of tinned meat and bread, had been stopped and burned. The driver fled. One of the men began to say something about the horses — a Russian stallion and a large pony.
It’s the Russian that drew the Oberst’s attention. The men laughed without looking as he mocked the horse, which made some effort at tapping or scratching in the mud. Officers have lately been shooting them. They no longer have the supplies to treat injuries. But no one can move the guns…
In the night, the horses make noises. A commotion wakes me, but I’m dreaming. I’m walking the horses out beyond the mud. There are trees, and it’s quiet.
The next morning the horses are gone. No one is laughing, everyone is hungry. The Oberst seems unsettled, as if he too woke from dreams of stillness and peace. A harried messenger on horseback comes to tell us we must remain where we are. That’s always the order. The Oberst seems puzzled by the messenger’s horse; he says nothing.24
One is reminded of Maeterlinck: “and his eye, melting with anguish, devours my mind.” Subliminal influences, mathematical intuitions, pictures of the future; dreams of unleashing the animals.
4.
In a short 1924 pamphlet, Theory of the War Dead, the French writer Jean-Baptiste Jolie speculates on the fate of millions of soldiers dead or missing in the Great War. He wonders at the numbers. An entire generation extinguished, Jolie puzzles over those who walked away.
Jolie was an amateur scholar, a French aristocrat living in London, dispossessed of his family’s land. He had studied military hospital records and battlefield lists. Not that such documents were always accurate, but he suggests an alternative to the vastness of the dead.
Although Jolie agreed that many millions had died, of course, he postulated as well that “war is a vanishing of men.”25 By which he meant that even the living vanish, that the hysteria of apocalypse in the trenches drove some men to refuse any chance at returning home. Not everyone could so easily resume their prior life.
It was Jolie’s belief that thousands of men walked away in the wrong direction, changed their names and remained forever lost, dead even at the end of a long life under another name. He points to strange but subtle swellings of population in certain distant cities at the edges of peacetime Europe. Millions died, Jolie agrees, yet perhaps some thousands or even millions of survivors simply chose never to go back. Some cool evening of the war, in the later months perhaps, they slipped the tether, walked down the ravine, and strode away into the night.
MH Rowe writes stories and essays. Find him online at his website or on Substack at Notes from the Neogene.
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Oskar Pfungst, Clever Hans, trans. Carl L. Rahn (New York: Henry and Holt, 1911), 16.
Phrenologists always chafe at being subjected to the tools of their own discipline: everyone worries his or her skull is suspect. Aside from the volume by Oskar Pfungst referenced above, additional biographical information on Wilhelm von Osten derives from Dieter Rauch’s short biography Meister von Osten (Berlin: Steller, 1915), which also references many contemporaneous newspaper accounts. Pfungst’s Clever Hans also cites numerous journals and papers.
Excerpts from select letters of von Osten originate in the appendix of Dieter Rauch’s Meister Von Osten, 120-145.
Pfungst, Clever Hans, 25.
Pfungst, Clever Hans, 21.
Pfungst, Clever Hans, 21-22.
Pfungst, Clever Hans, 22.
Carl Stumpf, Briefe, ed. Hugo Krauer (Leipzig: Blick, 1982), 34. The translations here and in the subsequent note are my own.
Stumpf, Briefe, 35.
Charles Darwin, The Expression of the Emotions in Man and Animals (New York: Penguin, 2009 [1872]), 39.
Sigmund Freud, The Ego and the Id, translated by Joan Riviere (New York: W.W. Norton, 1960 [1923]), 35.
Biographical information about Karl Krall derives from two sources, the first being his own Denkende Tiere [Thinking Animals], published in 1912 and still untranslated from the German. The book is long and detailed and includes a minute accounting of Krall’s own testing procedures with Clever Hans and other horses. The book is not without interest and includes excellent photographs. Krall remarks at one point that Hans “gave the impression of being apathetic and indifferent when it came to intellectual work” (my own translation). A not uncommon sentiment among patient and impatient horse owners alike. For our purposes, the main biographical source on Krall is of more direct relevance: Belgian writer (and later Nobel laureate) Maurice Maeterlinck’s The Unknown Guest, translated into English by Alexander Teixeira de Mattos and published in 1914. Maeterlinck’s book, which is a series of essays on paranormal or psychical phenomena, includes a long essay on Krall and Hans, whom Maeterlinck visited and observed.
Maurice Maeterlinck, The Unknown Guest, trans. Alexander Teixeira de Mattos (London: Methuen and Co., Ltd., 1914), 119. Cited page numbers are from a contemporary digital reproduction and may differ from original printed edition.
Maeterlinck, 125.
Maeterlinck, 128.
Maeterlinck, 143.
Maeterlinck, 142.
Maeterlinck, 174.
Maeterlinck, 167.
Édouard Claparède, “Clever Hans,” Revue neurologique, Spring 1919, 21.
Maeterlinck, 148.
Maeterlinck, 161.
Karl Krall, Elberfelder Briefe, ed. K.M. Horst (Berlin: Bauer, 1920), 18.
This excerpt from the rather elliptical letters of Adalfuns Schaum comes from a volume called Kriegsbriefe, 1914-1918 (Rosen, 1923). Translated by Herbert Grossman, the volume comprises “war letters” sent home by German soldiers.
Jean-Baptiste Jolie, Theory of the War Dead, translated by Jeremy Watson-Gabler (London: Holland Press, 2027 [1924]), 12.
An exquisite piece. Clever Hans > Little Hans!