All this is incontestable; and the facts are there, before which we must need bow. But what upsets all our convictions or, more correctly, all the prejudices which thousands of years have made as invincible as axioms, what we do not succeed in understanding is that the horse at once understands what we want of him; it is that first step, the first tremor of an unexpected intelligence, which suddenly reveals itself as human. At what precise second did the light appear and was the veil rent under? It is impossible to say; but it is certain that, at a given moment, without any visible sign to reveal the prodigious inner transformation, the horse acts and replies as though he suddenly understood the speech of man. What is it that sets the miracle working? We know that, after a time, the horse associates certain words with certain objects that interest him or with three or four events whose infinite repetition forms the humble tissue of his daily life. This is only a sort of mechanical memory which has nothing in common with the most elementary intelligence. But behold, one fine day, without any perceptible transition, he seems to know the meaning of a host of words which possess no interest for him; which represent to him no picture, no memory; which he has never had occasion to connect with any sensation, agreeable or disagreeable. He handles figures, which even to man are nothing but obscure and abstract ideas. He solves problems that cannot possibly be made objective or concrete. He reproduces letters which, from his point of view, correspond with nothing actual. He fixes his attention and makes observations on things or circumstances which in no way affect him, which remain and always will remain alien and indifferent to him. In a word, he steps out of the narrow ring in which he was made to turn by hunger and fear--which have been described as the two great moving powers of all that is not human--to enter the immense circle in which sensations go on being shed till ideas come into view. 22