I later tried similar experiments together with Mr. Hahn. I was aware of the answer to the riddle at the time, but he was not. Mr. Hahn stepped in front of the horse and thought intently of certain numbers. I did the questioning, that is, I got the horse to tap. In twelve tests Hans responded correctly in only two instances. In the ten others he always tapped beyond the number Mr. Hahn had in mind, e.g., 21 instead of 2, and was evidently awaiting a movement on my part. When we exchanged rôles, Mr. Hahn doing the questioning and I doing the "thinking," the horse would not respond at all, although as a rule Mr. Hahn had been fairly successful in working with him alone. I had gradually gained so much influence over the horse, that he would scarcely attend to any one else when I was about—Mr. von Osten hardly excepted.
In this connection I would prefer to avoid the term "rapport," which may rise in the minds of many, since it has been used so much in connection with the phenomena of hypnotism, for I would not obscure a fact that is clear by giving it a name that is vague.
CHAPTER III
THE AUTHOR'S INTROSPECTIONS
In the preceding chapter we asked: What is it that determines the horse's movements? Independent thinking, or external signs?—We found that it was solely external signs, which we described as certain postures and movements of the questioner. Beyond a doubt these necessary signs were given involuntarily by all the persons involved and without any knowledge on their part that they were giving any such signs. This is to be seen from their statements, which cannot be cavilled at, as well as from the fact that several of them even to-day still doubt the correctness of the explanation which we are here offering. I myself for some time made these involuntary movements quite unwittingly and even after I had discovered the nature of these movements and had thus become enabled to call forth at will all the various responses on the part of the horse, I still succeeded in giving the signs in the earlier naïve involuntary manner. It is not easy, to be sure, to eliminate at once the influence of knowledge and to focus attention with the greatest amount of concentration on the number desired, rather than upon the movement which leads to a successful reaction on the part of the horse. To some this may appear impossible, but those who are accustomed to do work in psychological experimentation, will not deny the possibility of such exclusive concentration upon certain ideas.
If we now ask: "What occurred in the mind of the questioners, while they were giving the signs?", the answer can be found only by way of the process which in psychology is technically called "introspection", i. e. observation of self. In the following we will give the most important results of this process of self-observation, which took place in the same period in which the observations recorded in the preceding chapter were made.
My first experiments were made while the horse was counting or solving arithmetical problems and were as follows: Mr. Schillings, who was alone with me in the horse's barn, asked me to think of several numbers, maintaining that the horse would be able to indicate them correctly upon being asked. He stood to the right of the horse, I stood erect and at the side of Mr. Schillings. There was no one else present. Somewhat skeptical in attitude, I concentrated my mind consecutively on five small numbers. Hans tapped one of them incorrectly, one correctly and three by one unit too many. At the time I considered these attempts as unsuccessful and credited some curious chance with the answers which were correct, or nearly so. This was a mistake, for often during the following days, and in the absence of Mr. von Osten, the horse would give correct answers. Others, of course, would be incorrect, and usually the mistakes would be by one unit,—so that I soon saw that even in the horse's errors there lay some system. It will be seen that Hans responded to me from the very beginning, undoubtedly because I had had the opportunity of watching