e 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 Mr. von Osten and Mr. Schillings and had
thus patterned my behavior after theirs. I was not at first successful
in getting the horse to respond correctly in the case of large numbers.
For in order to get complete control over the horse, and, what was, as
I later discovered, more to the point, control of myself, some practice
was needed. But I was able to work with the horse quite successfully,
while I was still in the dark as to my own behavior.

From the very beginning Hans responded as promptly to those questions
which I articulated merely inwardly, as to those which were spoken
aloud. That all formulation of the question was unnecessary, however,
was shown by the following experiments. If, for example, I did not think
of any particular number until after the horse had begun to tap, and
then fixed upon 5, he would tap 5. If, however, I told him to count to
6, but gave no further thought to the command after he had begun
tapping, I would get an entirely wrong response. It was easy to obtain
any answer one wished to a question, simply by focussing consciousness,
with a great degree of intensity, upon the answer desired. Thus Hans
answered my question: "How many angles has a hexagon?", first by 6, then
2, then 27, in accordance with the numbers that came into my mind. The
animal always followed the ideas which were in the questioner's mind,