Clever Hans Part 10

P. 28, 29, 217 [72]. When of two experimenters each tries to get the horse to tap a different number, then that one who is the better able to compel the animal's attention, will be the successful one.

("L'un veut faire prevaloire un chiffre pense plus considerable, l'autre un chiffre pense moins considerable.... Eh bien: l'operateur le plus puissant l'emporte." "Ainsi A est charge secretement de faire frapper 25 coups, B est charge secretement de l'arreter a 18; A l'emporte, et les 25 coups s'achevent.... On fait maintenant l'inverse: B est charge secretement de faire frapper 13 coups; A est charge secretement de l'arreter a 7; A l'emporte encore et le chiffre 7 ne peut etre depa.s.se.")]

The experience of a number of practical men, who have had much to do with horses and yet achieved but very modest success with Hans, goes to show that it is not always the lack of sufficient authoritativeness, mentioned under heading 1 that is the sole cause of failure, as has been claimed so often. That the horse was, to a certain degree, influenced by this element of authority is shown, however, by the following incident.

A certain gentleman, when alone in the courtyard with Hans, received responses only so long as I (concealed in the barn) kept the barn-door open just a little, so that my presence could be known to the horse. As soon as I closed the door, Hans refused to respond to the gentleman.

Those who possessed sufficient power of concentration and the requisite motor tendency--the two characteristics mentioned under 1 and 2 above,--were able to obtain responses from the horse without any previous practice. Practice merely effected a more economic distribution of attention, so that the larger numbers especially were more successful as a result (pages 68 and 89). Those who were lacking in either of the characteristics mentioned under 2 and 3 would not be aided even by the greatest amount of practice, as is shown by the case mentioned in Supplement III (page 255).--That many individuals were at first successful but were later unable to get any successful responses, is to be accounted for by the fact that the power of concentration, at first present, later rapidly disappeared. This temporary increase in the power of doing mental work was first investigated experimentally by Rivers and Kraepelin,[95] and was called by them "Antrieb" and aptly likened to the first pull of a team of horses in starting off. This, too, explains an experience which befell a number of the horse's visitors, who later described it to me. Wis.h.i.+ng to utilize a momentary absence of Mr. von Osten, they excitedly put a hasty question to Hans, and with amazing regularity received correct responses.--Besides Mr. von Osten, Mr.

Schillings and myself, not many were always able to induce Hans to bring the colored cloths or to execute the head movements. It was easy, on the other hand, to get him to nod. Therefore there was some truth in Mr. von Osten's a.s.sertion, that Hans would be unable to answer a difficult question if he had not previously indicated by means of a nod that he had grasped its import. Those who were not concentrating sufficiently, would not look into Hans's face, when he was expected to nod, and would not bend over, when Hans ought to begin tapping--such persons could not, therefore, since they did not induce Hans to nod, elicit the tapping. I, myself saw the "no" successfully elicited only in the case of Mr. von Osten, Mr. Schillings and Mr. Hahn; the "right" and "left" only in the case of the former two. It must remain uncertain whether this failure on the part of otherwise suitable persons to elicit the responses for "right" and "left" was due to their accompanying these ideas by movements of the eyes instead of by movements of the head, (page 106).

For unfortunately it was not possible to make special tests to discover whether Hans reacted to isolated eye movements. There is, however, more than one reason why I would doubt this. Taken all in all, there were but few persons who were entirely representative of the type described (c.

f. page 31)--they were those who are commonly characterized as being of a lively temperament and strongly impulsive. Thus Hans acquired a reputation for "Einkennigkeit", that is, he would accustom himself only to certain persons. Such a reputation was hard to reconcile with his much praised intelligence.

In closing, just a word on the influence of the public that was present.

As was shown on page 69, the public in general did not influence the horse in his reactions. The effect upon the questioner, however, was unmistakable, and worked in a twofold manner. On the one hand the questioner's zeal was increased and with it the tension of concentration. On the other hand, it introduced an element of diversion, and attention was divided between the horse and the spectators, and thus concentration suffered. If the disturbing effect was slight, as in the case of Mr. von Osten, then the favorable influence exercised by the presence of the public outweighed the unfavorable. Mr. von Osten was, for that reason, often particularly successful when working in the presence of a large body of spectators. This was noted by many and was ascribed to the ambition of the horse. When, however, a person was easily diverted, as was Mr. Schillings, then the presence of the public had a less fortunate effect.

This, then, completes my explanation of the facts gleaned from observation and experimentation. It accomplishes all, I hope, that may be expected of an explanation. All the known achievements of the horse, all the successes and failures of the questioner, have been reduced to a single principle; no secondary hypothesis has been invoked, and but slight place has been given to the element of chance. Nevertheless, it may not be out of place to forestall two objections which might possibly be raised. First, some may a.s.sert that it was through our experimentation that the horse became mechanized and incapacitated as regards conceptual thinking; that formerly he really could solve arithmetical problems, and only later developed the very bad habit of depending upon the signs which I gave him. This objection is to be refuted in that I did not originate these signs, but first noted them in Mr. von Osten, himself, and in that Hans still works as faithfully as ever for Mr. von Osten. I have learned from many trustworthy witnesses that the horse still continues to give brilliant exhibitions of his "ability". If, on the other hand, anyone should a.s.sert that it was only with us that Hans reacted to movements, but that with his master he really thought and still thinks, then I must ask for proof. This latter argument is by no means very original. When Faraday in 1853 proved experimentally that "table-rapping" is the result of involuntary movements on the part of the partic.i.p.ants standing about the table, the spiritualists a.s.serted that his experiments had nothing in common with their own proceedings, because his subjects (who by the way, had been up to that time firm believers in table-rapping) probably did move the table, they said, while they (the spiritualists) do no such thing.[96]

CHAPTER VI

GENESIS OF THE REACTION OF THE HORSE

In the preceding discussion we have regarded the achievements of the horse as well as Mr. von Osten's explanation of them, as matters of fact. Let us now consider the question: How did the horse come by these achievements, and how did its master arrive at his curious theory in explanation of them? Did he indeed seek to instill in the horse's mind the rudiments of human culture through long years of painstaking instruction in accordance with the method described in Supplement I (page 245)? If that is the case, then, of course his hoped-for success was only seeming, not real. Or did he, as so many critics aver, systematically train the horse to respond automatically to certain cues, and propound his theory merely for the purpose of misleading the public?

There might possibly be another alternative, viz.: was there a mixture of instruction and of training to respond to cues?

The production of the horse's achievements would not require a great deal of explanation, if it were a case of mere training for the purpose of establis.h.i.+ng certain responses to certain cues. It might be desirable, however, before deciding in favor of one of these possibilities, to indicate briefly the process of development, as it might occur, if the point of view is taken that _bona fide_ instruction was given.

This development would probably be as follows:--Mr. von Osten, as the result of theoretical speculation or of a misinterpretation of the facts of experience, having arrived at the conclusion that the horse possessed extraordinary capacity, finally undertook to instruct a certain horse for a period covering three years. This one having died, he, nothing daunted, undertook the education of another one. What it was that influenced this old teacher of mathematics to deprive humankind of the benefit of his extraordinary pedagogical ability and love of teaching, we do not know. It may be that he had had bitter experience in that line, or again, mayhap the newness and tremendousness of this other task stimulated him. His first problem must have been to arouse the interest of the animal in this process of education. It was hardly to be believed that Hans would eagerly cooperate in a process which promised to yield him no immediate benefit. The teacher sought to overcome this lack of immediate interest by the means of rewards. To Hans the sweet carrot was as toothsome a bite as candy is to the child. And since the horse was furthermore kept on low rations on account of the relatively low amount of physical exercise he took, the antic.i.p.ation of the carrots was doubly enticing.

The first thing that Mr. von Osten sought to teach the horse, according to his own statement, was the significance of the names of colors and of the spatial directions such as "up", "down", etc. In the case of children there is a simple test by means of which we may discover if they have put any content into these words. The test is: Do they, themselves, use them correctly? Do they call the blue, blue, and the red, red? Since the horse could not speak, his instructor had to give him some means by which he could make himself understood. He taught Hans to approach the colors and select the cloth of the color wanted. He also taught him to make those movements of the head or body which correspond with the expressions: "up", "down", etc.

First of all, Hans had to be taught to bring the cloths. Then began the pointing out of the different colors, accompanied each time by their proper names. It is very probable that at first Hans had to be led each time to each separate colored cloth and taught to raise it or to touch it with his nose. Later, Mr. von Osten, after having p.r.o.nounced the name of the color, remained at his place, with his head and body directed to the cloth in question and gazing intently at it, in order to see whether or not the horse was pointing out the right one. Naturally Hans would, at first, fail a hundred times where he would succeed but once, but since the horse would receive the antic.i.p.ated reward in case of success, he gradually became conscious that this reward was attached to executions which had some special mark. This special mark would be expressed in human speech by the statement that the horse would go in the direction indicated by the position of the instructor's body. For Hans, of course, this would not take the form of an abstract statement, but simply of a definite way of seeing and of going and a correlation of the two in a certain definite manner,--the whole being a process, the elements of which remained una.n.a.lyzed and unaccounted for by Hans. Owing to the position of the eye, it was possible for him to keep his master within his field of vision, while he was approaching the cloths. And only when he had correlated his approach in a certain definite manner with his visual perception of the master, i. e., only when he had felt his way, as it were, along the latter's line of vision, did he receive his reward. A sufficient number of repet.i.tions was all that was necessary to establish an a.s.sociation in the psychological sense of the term. In the same manner, dogs will learn, as was indicated on page 177, to bring an object upon which the master has fixed his gaze, it mattering little whether or not the name of the object be enunciated.

There is only this difference, that, in the case of the dog it is not possible to keep the image of the master within the field of vision; but neither is it necessary, for he has recognized the object before he has started for it. We must remember, however, that it does not simplify an attempt at explanation to a.s.sume that Mr. von Osten consciously trained the animal to respond to certain bodily positions of the questioner.

For, even in this case, it would be necessary to explain how it was possible for him to train the horse to heed the cues.--In the course of time, the instructor may have noticed that whenever he moved during the course of a test the horse invariably failed. But he may have regarded this merely as an incidental distraction and afterward was careful to remain quiet. As soon as he increased the number of cloths upon the floor, it was no longer possible for him to give the horse such accurate directive signs, and the number of errors consequently increased.

Ascribing them to the inattentiveness of his pupil, he sought to encourage him by such calls as "look out", "look there", "see there", believing that, thus, he was directing the horse's attention to the desired color. Without understanding the meaning of the calls, Hans learned, however, to keep moving just as long as the calling continued, for if he did this he was regularly rewarded. An a.s.sociation was established between the call and the impulse to move on. And with these two a.s.sociations established, Hans gave the impression of having grasped the meaning of the color terms.

The origin of the proper movements in response to the terms "up" and "down" may be explained by the fact that the movements themselves were practised in a purely external fas.h.i.+on. Thus, whenever the word "left"

was p.r.o.nounced, the horse's head was pulled to the left by means of the bridle or the reward was held off to that side. Later, Mr. von Osten, who looked expectantly at the horse's head, whenever he p.r.o.nounced the word would unconsciously move his own head in the direction in which he desired the horse to turn. This is quite in accord with the words of Darwin to the effect that whenever we wish an object to move in a certain direction it is well-nigh impossible for us to inhibit an unconscious, involuntary movement in that direction. Proof for this may be found on all sides, in daily experience.[97] Imagine, for instance, the strain sensations of the bowler or billiard player as he follows the moving ball. It is impossible to decide whether Mr. von Osten, consciously continued to image the head movements which he expected the horse to make or whether these antic.i.p.atory images later remained below the threshold as was always the case with Mr. Schillings and myself (see page 100). But this question is of little significance, for even a.s.suming that he always thought of the movement he expected on the part of the horse, this by no means implies that he was conscious of the movements on his part, which were a.s.sociated with the thought process.

Everything up to this point might be explained as the working of simple memory a.s.sociation, but when we come to problems in counting and arithmetical calculation, we are in the field of conceptual thought.

Here, again, it was necessary for Mr. von Osten to invent a suitable means of expression for the horse, and once more this had to be borrowed from the treasury of gesture-language. Tapping with the hoof was naturally hit upon as one of the normal, expressive movements of the horse. This has long been used by trainers, in preparing horses for show purposes. The method used in training the horse to make this response is of no import, whether it was by touching his foot with the hand, or tapping his leg, or by any other means.

It is possible that many will declare, as being nonsensical, any attempt to introduce number-concepts[AJ] into an animal's mind, because the necessary motor basis is lacking. We will not, just at this point, stop to discuss whether or not it was not possible to develop number-concepts from purely auditory or visual representations. It is evident, however, that Mr. von Osten believed that a motor basis of some sort was essential. In the case of man this basis is found in the enunciation of the number names (or in the manipulation of the fingers). Mr. von Osten seemed to think that he was justified in a.s.suming that, even in the case of the horse, some form of inner articulation of the word-sounds was possible;--at the same time, in so doing, he did not blink at the psychological difficulty of this hypothesis. The tapping of the foot was to be regarded merely as the expression of the process of inner counting, but not as the motor basis of the process. For this latter purpose tapping would be quite inadequate, for the number complexes which arise in the summation process of counting, could not be differentiated by mere tapping with the foot, any more than a child could learn to count by employing only one finger. Mr. von Osten evidently imagined the process was somewhat like this: Whenever Hans was about to count 5, he would enunciate inwardly the numbers from 1 to 5, and would accompany each word with a tap of the foot. Since, furthermore, wooden pins and b.a.l.l.s could be used--as in the case of children--for giving visual content in learning the significance of the number-terms, it seemed as if all the conditions necessary for the formation of number-concepts were supplied. However, the most essential thing had to be presupposed, viz.: that the horse virtually possessed the general power of forming concepts,[AK] and that all that had been lacking was the suitable conditions for its development. Mr. von Osten held tenaciously to this conviction, and it was this conviction that was the basis for the infinite patience with which the tests had been pursued.

[Footnote AJ: The author intends to take up the problem of counting, so-called, on the part of animals and of the principle involved, in another work soon to be forthcoming.]

[Footnote AK: There are some who believe they are warranted in concluding the opposite from the structure of the animal's brain alone. We may say that the brain of the horse, compared with that of the ape, or even that of the dog, represents a relatively low type of development. But owing to the rapid changes in the views, often contradictory, concerning the nature of the nervous structures and processes underlying the thought process, any conclusion based on such views would be premature. For this reason we cannot agree with the French physiologist who was dissecting the brain of a horse and, struck by its smallness of size, exclaimed: "When I saw your proud look and beautiful neck, I hesitated a moment before mounting upon your back. But now that I have seen how small is your brain, I no longer have any qualm about using you."[98]]

To come now to the learning process itself;--we may a.s.sume that, at first, whenever the horse began to tap in response to commands, he would receive a reward for this purely mechanical feat. Wooden pins were then planted on the ground and designated as: one, one two, etc., and each time someone would raise the horse's foot as many times as the count demanded (see Supplement I). Then Mr. von Osten would take his stand at the horse's side and would command him, let us say, to tap 3. Hans noting merely (from his master's position) that he was expected to tap, would begin. The instructor, who had bent forward in order to watch the horse tapping,[AL] would involuntarily straighten up again at the third tap, without being conscious of it and quite unaware that he was thus giving a signal. The horse would be startled, and sometimes he would immediately cease tapping and sometimes not. But it was only in the first case that he would receive a reward. Thus, unknown to the instructor, an a.s.sociation became established between the sight of the upward jerk of the instructor and the act of ceasing to tap. To be sure, the animal would receive sundry visual impressions from the wooden pins set up before him and the auditory stimulations of the spoken number names, on the basis of which, the concepts were to be formed in his mind. But in this chaos of visual impressions (at times there were two wooden pins, then three, then four, sometimes there were the pins, at others, the b.a.l.l.s of the counting-machine)--and in the babel of word-sounds--which evidently meant nothing but noise to him--amidst all this there was but one constant element: the final movement of the instructor's body. The moment the horse reacted to this, he would receive the tidbit at the hands of his overjoyed master, and thus he became more and more accustomed to attend to this jerk, even after it had gradually decreased in scope. And the reason again, why this jerk tended to become less p.r.o.nounced was that the tests were gradually becoming more and more successful. For, corresponding to the degree in which the horse began to react properly, the instructor's tenseness and excitement tended to decrease, and with this decrease of the emotional element in the man's consciousness, the accompanying non-voluntary, expressive movement gradually became less p.r.o.nounced until it attained that extraordinary refinement which it possesses to-day. We noticed also, that whenever the horse, for any reason, had to be trained anew, Mr. von Osten's movements would, on the whole, become somewhat more gross, as for instance after the tests with the blinders. There is not a shadow of a doubt that this increase in the movement's extent was entirely unintentional, since the horse could not see his master at all on account of the blinders which had been attached to the trappings.

[Footnote AL: This natural and close connection between the process of attention and the movement toward the object attended to is clearly expressed in our English and French terms, derived from the Latin "tendere ad--," to reach toward--.]

In the same way it is possible to explain the details. Mr. von Osten himself said that at first Hans had tapped at times with his left foot, at times with his right, just as he pleased. But later his master taught him to tap only with the right. Whenever he began with the left, Mr. von Osten would immediately interrupt him, and he was allowed to add only a final tap with his left foot. Thus, this additional tap which was sometimes made with the left foot was but the vestige of an earlier rudimentary habit. The signal for it was the stooping posture in which the master remained after the head-jerk had been made. Whenever Mr. von Osten had given Hans a small number to tap, he would bend forward only a little. But when he expected a larger number he would bend forward somewhat more, owing to the desire to observe the tapping more carefully. From the slight inclination of the master's body the horse would get the cue that he was expected to tap for a short time only, by the greater degree of inclination he would know that he was to tap for a longer period. In the second case he tapped rapidly and did not raise his foot as high from the ground--evincing a regard for the saving of energy, which may well be attributed to a horse. And thus arose the connection between the degree of inclination of the instructor's body and the horse's rate of tapping.

So, now that the ability to count and solve problems had become fixed--as the old gentleman thought--he began to instruct the horse in other branches. Since everything had been translated into terms which were to be expressed by means of tapping with the foot, and thus really put into terms of number--which was perhaps natural for an old teacher of mathematics--the same mechanism was involved in these accomplishments as in those of counting, etc. Mr. von Osten saw the animal's intelligence steadily increase, without having the slightest notion that between his words and the responsive movements of the horse, there were interpolated his own unconscious movements--and that thus instead of the much desired intellectual feats on the part of the horse, there was merely a motor reaction to a purely sensory stimulus. It has been a common custom of man to posit some extraneous cause for movements resulting from certain involuntary motions of his own, of which he is not aware, (witness the divining-rod).[AM] And furthermore, when these results appear to be rational, the tendency is to seek their cause in some extraneous intelligence, not his own. Just as the spiritualists ascribe the "messages" which are revealed to them through table-rapping, to certain rational spirits, so Mr. von Osten credited the intelligence of the horse with the result produced by his own involuntary signs--i.

e., with the proper solution of problems.

[Footnote AM: G. Franzius,[99] privy counselor of the admiralty, master of the dry-dock at Kiel, is responsible for the undeserved revival of the ancient belief, long buried by science, that the divining branch is put into motion solely as the result of the influence of hidden springs or treasures, and without any agency in the person who is holding it. The untenability of this theory comes home to us most forcibly when we recall how various are the kinds of things which have been discovered by means of the branch. First there is gold and water, which are the only ones mentioned by Mr.

Franzius. The water can be thus discovered only when it flows below ground, say that which is pa.s.sing through the mains of a city, whereas the water of the Rhine or the Elbe would have no effect on the branch. Besides gold, every other kind of metal has been supposedly located by the branch,--as well as coal, gypsum, ochre, red-chalk sulphur and petroleum,--according to the desire of the one searching. Thus, the very same branch that just a moment ago was influenced by the least bit of underground water, may remain unaffected by the presence of a large body of water, if in the meantime I have changed my plan and decide to search for coal or for gold. But that is not all. The branch will point out a murderer or the place where a murder has been committed, it will discover the thief or his trail, as well as the things stolen or merely touched by him. It will indicate where the boundary-stone that has been moved, ought to stand. The branch further discloses the sins of the persons concerning whom it is consulted, as well as their talents and abilities, the journeys they have made and the wounds they have received. It will indicate whether or not a person has money and how much. It can announce what absent persons are doing and what apparel they are wearing, and of what color it is. It will give information on theological, medical, zoological, and botanical questions. In fine, no matter what the question, it will never fail of an answer.[100, 101]

The impossibility of explaining the phenomena in a purely physical way was recognized at a very early date. For a long time the activity of the users of the divining rod seems to have been restricted to the search for metals. The first (or one of the first) to raise his voice against it was the learned G. Agricola[102]

(1556), and after him there were many who all wrote more or less independently of one another. Aside from swindle and chance, it was usually believed that sorcery of the agency of Beelzebub was involved, and for that reason the Church has repeatedly forbidden the use of the divining-rod. But even in the 17th century we find some who believed that it was imagination alone that moved the person's hand, and with it the rod,[103, 104] ("forta.s.sis etiam phantasia manum in motum concitante"); and that points out the essentials of the solution of the phenomenon, and we will not go into the matter here in detail. A number of complex psychological problems arising in connection with it are still waiting to be solved, but this much appears certain; the staff or branch plays no other part in the whole process than that which is served by the three levers in the tests described in Chapter IV (pages 116 ff.),--they simply magnify the expressive movements of the diviner.

And so we can understand why the instruments serving as rod might be so varied. Hay-forks, pickets, clock-springs and pendulums, scissors and pliers have been used. A knife and fork or two pipes, fastened together, an open book, and even a sausage, grasped at both ends and thus bent together somewhat,--all have served the purpose equally well. We can understand, too, how some adepts are able to achieve the same degree of success--for they do succeed beyond a doubt--without any rod whatever, but simply by placing the index fingers end to end and bending them somewhat, and even by merely groping about with hands outstretched or folded before them.[106]]

Two other phenomena may have tended to strengthen Mr. von Osten's belief in Hans's intelligence. One was the misleading similarity with which the horse's supposed errors in computation and the poorly adjusted concentration of the questioner, were expressed. We recall the difficulty in the case of very high numbers. This might easily be considered as being due to the horse's ability to work more readily with small, rather than with large numbers, whereas, as a matter of fact, it was due solely to the difficulty of the questioner to keep his attention concentrated upon the number for so long a time. We recall also the frequency of errors of one unit too few and one unit too many. These were easily interpreted as miscounts on the part of Hans, but in truth were the result of the poorly concentrated attention of the questioner.

Added to this was the seeming independence and self-sufficiency of the horse. Often the number given by him was other than that desired by his master. Usually Hans was in the wrong in such cases, but sometimes, too, he was right. At any rate, this served to give the impression of independence of thought which his master so thoroughly believed he possessed, and which was the goal of his endeavors--though as a matter of fact he was farther removed than ever from that goal.

Some may ask: Does not this whole process partake of the essentials of all training, (though c.u.mbersome and misunderstood, to be sure), and is there any need of investigating whether or not the actual development was of the sort here outlined, or whether it actually took the course common to all training?

In order to answer this question we must determine more specifically what we mean by the term "training". Usually we take it to mean the establishment in the animal, of definite habits of motor reaction in response to certain stimuli purposely selected by the trainer, and without involving any process of animal consciousness other than a.s.sociation. Such a conception may be applied also to man, if we a.s.sume that the higher thought processes can be eliminated. If that were the case, the above definition would not have to be changed, not even with regard to the word "animal", for we must take it in the antique sense of "zoon", a signification readopted by modern zoology. The concept may be widened, however, by omitting the differentia of "purpose", or even more, by including the habitual a.s.sociation of ideas or images (instead of movements) with certain sensory stimuli. But in so doing, we must bear in mind that we are going beyond the usual content which in everyday practice is put into the term "training". Especially, when we cease to regard the presence of purpose in the trainer's mind (both in giving the stimulus as well as in the habituation of the animal to them) as essential. When this is done, the conception of training really resolves itself into the much wider conception of habit-building, and the whole discussion becomes merely a quarrel over words. In order to obviate this, let us bear in mind that in the following, the word "training" is always taken in the usual and narrower sense. The term then is still ambiguous only in so far as it has not merely its original significance of the _act_ of purposely habituating (a person or an animal) to perform certain definite movements, but by transference is also used to denote the _effect_, i. e., the occurrence of the movements in question. But this does not really detract from the clearness of the concept itself.

Having cleared up the question of definition, let us return to our original problem: Does the hypothetical account of the probable development of the horse's reactions, which is given on pages 213 to 220, represent a case of training? This must be denied decidedly with regard to the tapping of numbers and the solution of arithmetical problems. For here the sensory stimuli which were purposely given, i.

e., the wooden pins, the b.a.l.l.s, and the spoken words, were intended to subserve the function of arousing not movement, but thought processes in the horse; whereas the function of the horse's movements was to give expression to these thought processes. Of the really effective stimuli--the slight movements on his part--the master was never conscious, much less were they purposely made. The same holds true for the "up" and "down", "yes" and "no", etc., for here also Mr. von Osten counted upon the rise of the corresponding concepts, and not merely upon a purely external, mechanical a.s.sociation of meaningless sounds with certain movement-responses on the part of the horse. This might also explain the genesis of Mr. von Osten's belief that Hans was able mentally to put himself in the place of the questioner, (page 19). At any rate it is very improbable that he, Mr. von Osten himself, clearly distinguished between the concept: "up" and the sound of the word "up".

When we come to consider the horse's selection of the colored cloths, and even more his leaping and rearing, we find that the distinction between "training" and "instruction" vanishes. If we had to deal only with this cla.s.s of achievements, we might perhaps say, without fear of going very far wrong, that the only difference between this and the ordinary form of training was that Mr. von Osten had intended to train the horse to respond to auditory signs (words), but had unintentionally trained him to respond to visual signs instead. But it is not this type of performance that has become the bone of contention. Just as it would be misleading to maintain that Mr. von Osten's effort was nothing other than a case of training, so it also would be unjustifiable to designate the results of his effort by that name, since the really effective stimuli were not, as has been pointed out just now, given intentionally.

As far as the horse is concerned, it is a matter of indifference whether or not really effective stimuli were given intentionally by the questioner. The animal knows nothing of human purposes and if he were transferred to a circus, he would find nothing new in the method employed there, except the use of the whip. We, however, define our concepts from the human and not from the horse's point of view. We may definitely say, therefore, that the method described cannot be regarded as that of training, neither in its application nor in the effect produced, though in the latter it closely simulates the effects of the training method.

Having thus differentiated between the methods of instruction and training, let us now attempt to decide on the basis of such indications as we may possess, which of the two was actually represented by the development of the horse's attainments. Surveying the facts which we have at hand, we may say that there are hosts of reasons why we cannot a.s.sume that it was a case of training. Everything that we know from our own observation and from the well-attested statements of others, with regard to the actual process of instruction, weighs against the a.s.sumption. Another evidence of this is the long period of time which Mr. von Osten required (both in the case of Hans, as well as with his predecessor), whereas the same end would have been much more speedily attained if it had been a case of training. A further argument is the fact that a large horse was selected for the purpose, whereas a small mare would have been far more suitable, (c. f., "Clever Rosa", page 7).

Again, the whip, that sorcerer's rod of all professional trainers, was here absent. And finally, many traits of character of Mr. von Osten, as well as his conduct during the whole course of events, militate against such an a.s.sumption. He generously turned the horse over to us, as he had given it over to Count zu Castell, Count Matuschka and Mr. Schillings.

He eagerly besought a scientific investigation. He had made several reports to different ministries. All of these acts could only hasten the denouement. What could have been his motive? Some thought they detected an effort at pecuniary speculation, and an advertis.e.m.e.nt of June, 1902, in the "Militarwochenblatt", in which Hans was offered for sale, seemed to confirm the conjecture. Mr. von Osten says that this occurred at a time when he himself was sick and had become tired of the job. And why should he not be willing to sell even a thinking horse, since he had become convinced that any other could be instructed in the same way?

Besides, I have it on good authority that after the publication of the September report he received several exorbitant offers; to mention only one of them: a local vaudeville company was ready to pay him 30,000 to 60,000 marks per month. He refused every one of these offers. Some may say that perhaps he wanted still more. But if he knew that the day of judgment was close at hand, he also knew that before then, if ever, was the suns.h.i.+ny day on which to make his hay. A more auspicious time he could never hope to see again.--Let us add, once more, that he never charged admission to any of Hans's performances, although there were many who were anxious to see the horse, and many enthusiasts had come from a great distance. And finally, he was an old man, unmarried and entirely alone, a property owner, but a man whose wants were few and very simple--and his Hans was almost his sole companion. Is it possible that such a man, one who had all the pride of gentle birth, would become a trickster in his old age, all for the love of money?

The unreliability of Mr. von Osten's signs is good proof of their involuntary nature. Anyone who had seen him work with the horse could not have helped noticing that he certainly did not have complete control over the animal, and was not able, at a given moment, to make Hans perform a certain feat, as would have been the case if the process had been one of "training". Again and again Hans failed to make the right count. Before a large audience, one time, it took four tests to get him to tap properly up to 20, and in all four I could note clearly that it was Mr. von Osten who, by his involuntary premature movements, was the innocent cause of the failure. On another occasion, after Hans had done some beautiful work in fractions, in the presence of a large number of spectators, the master asked him the simple question: "Where is the numerator in a fraction?"--The answer was first: "to the left", and then, after a severe reprimand: "down" (below), and finally: "up"

(above). He often made just such incorrect movements of the head. In the color-selecting tests the average of error was quite unpredictable. With an equal number of tests, on one day, half would be successful, on another, four fifths, on a third, one-tenth. Often Hans appeared to be "indisposed" for days at a time. The color tests would often end in expressions of rage on the part of Mr. von Osten and in consequence Hans would become startled and would then storm about the courtyard so that it was dangerous to try to approach him. Some may object that all this was mere comedy and that possibly Mr. von Osten prevented some of the tests from turning out successfully. But this objection is to be met by the statement that very often failure would occur just when it was particularly desirable to have the tests appear in a favorable light before a large and enthusiastic a.s.semblage of visitors. After such failures he would be downcast on account of Hans's contrariness. It is also significant that Mr. von Osten's percentage of error, corresponds very closely with my percentage of error in the "non-voluntary" tests, (page 84f.), whereas he never was able to obtain the errorless results which I obtained in my "voluntary" experiments.

But we must be careful not to confuse non-voluntary movement and lack of knowledge of the movement. And again we must distinguish between knowledge of the grosser and the finer signals. Mr. von Osten was aware of the grosser movements, and talked quite freely concerning them, but in so doing, showed that he was quite unaware of their true function. He undertook to show us what we already knew--that, when he remained standing perfectly erect, he could elicit no sort of response from Hans.

Furthermore, that whenever he continued to bend forward, Hans would always respond incorrectly and with very high numbers. He knew, also, that Hans was distracted in his operations every time the questioner resumed the erect posture while the tapping was in progress. This he demonstrated to us on one occasion in the following manner. He said to Hans: "You are to count to 7; I will stand erect at 5". He repeated the test five times, and each time Hans stopped tapping when the master raised his body. Several such tests resulted in the same way. Mr. von Osten, however, believed this to be a caprice of the horse and at first declared that he would yet be able to eliminate it, but later became resigned to it as an irremediable evil. Mr. von Osten was also aware that the questioner ought not move while the horse was approaching a colored cloth, and cautioned me in regard to it, though I had already noted as much. And finally, he also knew what influence his calls had while the horse was selecting the cloth, and he told me that it was of great a.s.sistance to Hans to be admonished frequently, since thus his attention was brought to bear upon the proper cloth. Yet, when we requested Mr. von Osten to desist calling, since he was thereby influencing the horse in the choice of the cloth, he answered: "Why that's just what I wish to do!"--But though the statement that he was aware of the nature of these grosser signs is thus seen to be true, it by no means necessarily implies that he had purposely trained the animal to respond to them. In these observations of his he had builded better than he knew--he evidently had no notion of their scientific significance. But the same thing might happen to those who were supposed to be somewhat less nave, as is shown by the experience of Mr.

Schillings, who quite unconsciously, for many months had been giving not only the finer, but also the grosser signs, and never guessed the true nature of affairs until I explained it to him. Nor was it an easy matter for me to get at the facts involved in the process, although it now all appears so very simple.

On the other hand, it is also true that Mr. von Osten knew nothing whatever of the finer, more minute signals, such as the final jerk, the head-movement upward, downward, etc., and it is difficult to conceive how he might have gained any knowledge of them. We might perhaps conceive of four possible sources. He might have come upon them by chance. But it is extremely improbable that in the million of possible forms of signaling he should have hit upon those that at the same time represent the natural expressive movements. Or he might have derived a knowledge of them through a study of the pertinent literature. I have searched diligently for such a source, in both the old and the modern literature, but in vain. From the sixteenth century on, there is a series of accounts of horses that were able to spell and to solve problems in arithmetic, and the reports on learned dogs go back even to the time of Justinian, in the middle of the sixth century.[107] All of these animals were kept for purpose of speculation and were exhibited for pecuniary reasons only. Nor does one read that any person could work with these animals off-hand, which was the characteristic feature of the Osten horse.[AN] In many cases we find mention made of the signs to which the animals reacted. Thus for the beginning or stopping of the animal's sc.r.a.ping or tapping, the signals were respectively raising and lowering of the eyes on the part of the trainer,[113] lowering and raising of the whip[114] or of the arm, stepping forward and backward,[115] and as a closing signal a slight bending forward.[116]

The signals for beginning and ceasing to bark in the case of dogs, were the trainer's commands to "speak", and, at the same time, his looking at the dog, and then looking away for a closing sign;[117] or a mouth-movement on the part of the trainer and then a withdrawing of the left hand which had been resting on the hip.[118] Among the signals for nodding and shaking the head we find the following mentioned: raising and lowering the hand or arm[119] or the whip;[120] a movement of the hand toward the horse's nose, as a signal for nodding, and an arm-movement as a signal for shaking the head.[121] For this last, we find recommended also a slight breathing upon the animal,[122] and--in the case of dogs--a mouth-movement simulating blowing, or a turn of the fingers.[123] (We will not dwell upon the many signals for selecting objects, which are mentioned, since we have already discussed this point on page 230f). In all these instances it is plain that we have to do with purely voluntary and "artificial" signals. The only example of involuntary signs which Mr. von Osten could have found in literature, was that of Huggins's dog, which need not be considered here, since, as was said on page 177, the really effective signs in that case were not discovered. A third means by which Mr. von Osten might have gained a knowledge of the involuntary, natural expressive signs, would have been by observing others. If he had had opportunity of observing another von Osten and another Hans, he might have gotten at the secret. But since this was not the case, this possibility vanishes. A fourth possibility is self-observation. We would then have to a.s.sume that Mr. von Osten at first really tried to educate the horse to think, but soon recognized the fruitlessness of such an attempt. At the same time, he then would have noticed his own involuntary movements and their effect upon the horse, and having noted them, voluntarily reduced their extent and utilized them in the training process. But here also there is much that militates against this a.s.sumption when we consider how great is the difficulty of consciously refining movements which at first were rather coa.r.s.e, unless it be by the adjustment of the proper degree of concentration of attention, a subtlety of method of which we could hardly believed Mr. von Osten capable. We must remember, also, that in the first publication regarding Hans which, by the way, marks the beginning of his career, ("Das lesende und rechnende Pferd," by Major-General E. Zobel, in the "Weltspiegel" of July 7, 1904), we may read the following: "He (Mr. von Osten) is always willing to have the horse undergo an examination on the part of a stranger, and promises that after Hans has become fairly well acquainted he will display the same degree of efficiency as he displays with the master, himself."

This occurred at a time when Mr. Schillings, the man who was destined to prove the truth of the statement, had not yet appeared on the scene. How was Mr. von Osten to know beforehand that every questioner, who might appear, would execute the same movements that he himself had used? We would recall also that not one in the great mult.i.tude of persons who worked successfully with the horse in the absence of Mr. von Osten, had noticed, even in the slightest measure, any of these movements in themselves. The position and repute of these persons vouches for their veracity,--among them were the writer of the article just mentioned, the Count zu Castell, Count Matuschka, Count von Eickstedt-Peterswaldt, General Koring, Dr. Sander, Mr. H. Suermondt and Mr. H. von Tepper-Laski. Some of these gentlemen were quite unwilling to believe that they executed such movements. This happened in the case of Mr. von Tepper-Laski, who had visited Hans ten times and who had, during the course of these visits, frequently worked alone with the horse and had received correct responses. Count Eickstedt, too, although he was one of those who had been made acquainted with the nature of the movements involved before being allowed to visit the horse, was unable to note them either in his observation of Mr. von Osten, or of himself, when, in compliance with his own wish, he was left alone with Hans. Nor did any of the laboratory subjects, some of whom were well trained in introspection, discover the true nature of affairs. They were thoroughly astonished when the facts of the case were explained to them. And I, also, as was mentioned on page 100, did not become aware of my own movements, until I had noted those of Mr. von Osten. In fine, everything would indicate that we have here not an intention to deceive the public, but a case of pure self-deception.[AO]

[Footnote AN: There is only one, and I believe it is only a seeming exception to be found in the literature on the subject. We are told that about the year 1840 a French revenue official named Leonard had two hunting dogs that, besides other things, were able to play at dominoes, and this not only with their master, but with anyone and without the master's a.s.sistance. The owner had educated them simply for the fun of it, and not for pecuniary gain. This statement is made by both writers who, apparently independently of one another, have discussed the case, Youatt[108] and de Tarade.[109] De Tarade himself played with them, and gives directions how to teach dogs to play the game. But his exposition is so nave, and even ridiculous, for those who know anything about the subject, that we do not believe it necessary to attempt a detailed refutation. Youatt never saw the animals. But he tells us that not only the dog's partner, but also the master, sat at the game. Youatt's a.s.sertion, however, that "not the slightest intimation could have been given by Mr.

Leonard to the dog," but that the animal carried on the game by means of its own observation and calculation, appears to me a rather bold statement. After my own experience with dogs, I firmly believe this to have been impossible. Hachet-Souplet,[110] who shares my conviction, explains the matter as follows: the dog would simply place a domino having the number of eyes named by his partner, thus the 6 adjacent to the 6, the 3 to the 3, etc. But even so a great deal would have to be attributed to the dog, (although in that case real counting would by no means be absolutely necessary, for an a.s.sociation between the number term and the total picture of the corresponding group of eyes would suffice.) But we must note that neither of the writers mentions that the numbers were always called aloud by the partner. After the failure of the experiments of Sir John Lubbock,[111] we must doubt very much if a dog is able to match one domino with another having the same number of eyes. We are therefore inclined to believe that this dog continually received signs from its master. These signs probably were visual, perhaps also auditory, and they were by no means involuntary. For in a book on the training of animals, which Leonard, the owner of the dogs, has published, and in which he describes minutely the method by which they had been trained in their various accomplishments, he does not mention with so much as a syllable the game of dominoes, a thing which he certainly would have dwelt upon, if he had believed in the animals' power of independent thought. He would not have remained silent concerning this greatest--though only apparent--achievement of his educational endeavors. But his whole book is evidence that he was too wise to have thus deceived himself, and our only alternative is to believe that he was playing a joke on his credulous admirers.]

[Footnote AO: P. Wasmann, S. J. in the third edition of his book, "Instinkt und Intelligenz im Tierreich" (Freiburg, Herder, 1905), discusses the case of Hans and quotes from a letter I wrote him concerning the matter. In the quotation an error has crept in, which I would here correct. The statement is ascribed to me that "Hans differs from other horses only in his extraordinary power of observation, an unintentional by-product of intentional training,"

whereas in my letter I said: "unintentional by-product of intentional education."]