The horse failed in his responses whenever the solution of the problem that was given him was unknown to any of those present. For instance, when a written number or the objects to be counted were placed before the horse, but were invisible to everyone else, and especially to the questioner, he failed to respond properly. Therefore he can neither count, nor read, nor solve problems in arithmetic.
The horse failed again whenever he was prevented by means of sufficiently large blinders from seeing the persons, and especially the questioner, to whom the solution was known. He therefore required some sort of visual aid.
These aids need not, however,—and this is the peculiarly interesting feature in the case,—be given intentionally. The proof for this is found in the fact that in the absence of Mr. von Osten the horse gave correct replies to a large number of persons; and to be more specific, Mr. Schillings and later Mr. Pfungst, after working with the horse for a short time, regularly received correct answers, without their being in any way conscious of having given any kind of signal.
So far as I can see, the following explanation is the only one that will comport with these facts. The horse must have learned, in the course of the long period of problem-solving, to attend ever more closely, while tapping, to the slight changes in bodily posture with which the master unconsciously accompanied the steps in his own thought-processes, and to use these as closing signals. The motive for this direction and straining of attention was the regular reward in the form of carrots and bread, which attended it. This unexpected kind of independent activity and the certainty and precision of the perception of minimal movements thus attained, are astounding in the highest degree.
The movements which call forth the horse's reaction, are so extremely slight in the case of Mr. von Osten, that it is easily comprehensible how it was possible that they should escape the notice even of practised observers. Mr. Pfungst, however, whose previous laboratory experience had made him keen in the perception of visual stimuli of slightest duration and extent, succeeded in recognizing in Mr. von Osten the different kinds of movements which were the basis of the various accomplishments of the horse. Furthermore, he succeeded in controlling his own movements, (of which he had hitherto been unconscious), in the presence of the horse, and finally became so proficient that he could replace these unintentional movements by intentional ones. He can now call forth at will all the various reactions of the horse by making the proper kind of voluntary movements, without asking the relevant question or giving any sort of command. But Mr. Pfungst meets with the same success when he does not attend to the movements to be made, but rather focuses, as intently as possible, upon the number desired, since in that case the necessary movement occurs whether he wills it or not. In the near future he will give a special detailed report of his observations, which gives promise of becoming a valuable contribution to the study of involuntary movements. Also he will give an account of our tests and of the mechanism of the various accomplishments of the horse. We must also defer, till then, the disproof of certain seemingly relevant arguments in favor of the horse's power of independent thought.
Some defenders of the view which maintains the horse's rationality may urge that it was only through our experiments that the animal became trained and spoiled in so far as the ability to think is concerned. They are refuted in this, however, by the fact that the horse still continues to solve problems involving decimal fractions and to determine calendar dates for Mr. von Osten, as brilliantly as ever, as is shown by his recent demonstration before a large group of spectators. That these results are now being achieved in a manner essentially different from formerly is nothing but a bare assertion.
On the other hand, now that the possibility has been established that these wonderful results may be obtained in all their complexity by means of intentional signs, many will question whether Mr.
von Osten did not himself train the horse from the very beginning to respond to these signs. No one has the right, however, to charge an old man, who has never had a blemish on his reputation, with having invented a most refined network of lies, if the facts can be explained in a satisfactory manner in some other rational way. And this can be done in this case. For we have seen that there is another alternative, other than the theory that the horse can think or the assumption that tricks have been employed.
And now, aside from the specific results obtained, what is the scientific and philosophic import of the whole affair?—For one thing, the revolution in our conception of the animal mind, which had been hoped for by some, and feared by others, has not taken place. But a conclusion of an opposite character is justified. If such unexampled patience and high pedagogical excellence as was daily brought to bear by Mr. von Osten during the course of four long years, could not bring to light the slightest trace of conceptual thinking, then the old assertion of the philosophers that the lower forms are incapable of such thinking, finds corroboration in the results of these experiments so far as the animal scale up to and including the ungulates is concerned. For this reason the tremendous effort put forth by Mr. von Osten, is not, in spite of the self-deception under which he labors, lost to science. If anyone has the courage to try the experiment with the dog or the ape, the insight which we have now gained will enable him to beware of one source of error which hitherto has not been noticed.
In the face of much misapprehension which has arisen, I wish once more to say emphatically that the committee of September 12th in no wise declared itself to be convinced that the horse had the power of rational thinking. The committee restricted itself entirely to the question whether or not tricks were involved, and, intentionally and rightly referred the positive investigation to a purely scientific court. I would also report that for some time Mr. Schillings has been convinced, by his own observations, of the horse's lack of reason, and when he was apprised of our conclusion in the matter, he embraced it without wavering. I have no intention of taking part in any discussion which may arise in the press as a result of the present report. Unless they wish to confine themselves to mere guesswork, the defenders of other views will not shrink from the task of basing their criticism upon careful methodical experimentation, and they will keep a detailed record of their results day by day; for statements based solely upon memory, without specific report of experimental conditions, prove nothing.