If we would make a brief summary of the status of Mr. von Osten's horse in the light of these investigations and try to understand what is the bearing upon the question of animal psychology in general, we may make the following statements.

Hans's accomplishments are founded first upon a one-sided development of the power of perceiving the slightest movements of the questioner, secondly upon the intense and continued, but equally one-sided, power of attention, and lastly upon a rather limited memory, by means of which the animal is able to associate perceptions of movement with a small number of movements of its own which have become thoroughly habitual.

The horse's ability to perceive movements greatly exceeds that of the average man. This superiority is probably due to a different constitution of the retina, and perhaps also of the brain.

Only a diminishingly small number of auditory stimuli are involved.

All conclusions with regard to the presence of emotional reactions, such as stubbornness, etc., have been shown to be without warrant. With regard to the emotional life we are justified in concluding from the behavior of the horse, that the desire for food is the only effective spring to action.

The gradual formation of the associations mentioned above, between the perception of movement and the movements of the horse himself, is in all probability not to be regarded as the result of a training-process, but as an unintentional by-product of an unsuccessful attempt at real education, which, though in no sense a training-process, still produced results equivalent to those of such a process.

All higher psychic processes which find expression in the horse's behavior, are those of the questioner. His relationship to the horse is brought about almost wholly by involuntary movements of the most minute kind. The interrelation existing between ideas having a high degree of affective coloring and the musculature of the body, (which is brought to light in this process), is by no means a novel fact for us. Nevertheless, it is possible that this case may be of no small value, on account of the great difficulties which are usually met in the attempt to establish experimentally the more delicate details in this field.

And, returning to the considerations of the first chapter, if we ask what contributions does this case make toward a solution of the problem of animal consciousness, we may state the following: The proof which was expected by so many, that animals possess the power of thought, was not furnished by Hans. He has served to weaken, rather than strengthen, the position of these enthusiasts. But we must generalize this negative conclusion of ours with care,—for Hans cannot without further qualification be regarded as normal. Hans is a domesticated animal. It is possible (though the opposite is usually assumed), that our animals have suffered in the development of their mental life, as a result of the process of domestication. To be sure, in some respects they have become more specialized than their wild kin, (e.g., our hunting dogs), and in their habits they have become adapted largely to suit our needs. This latter is shown by all the anecdotes concerning "clever" dogs, horses, etc. But with the loss of their freedom they have also gradually been deprived of the urgent need of self-preservation and of the preservation of their species, and thus lack one of the greatest forces that make for psychic development. And often their artificial selection and culture has been with a view to the development of muscle and sinew, fat and wool, all at the expense of brain development.[AP] Our horses are, as a rule, sentenced to an especially dull mode of life. Chained in stalls (and usually dark stalls at that,) during three-fourths of their lives, and more than any other domestic animal, enslaved for thousands of years by reins and whip, they have become estranged from their natural impulses, and owing to continued confinement they may perhaps have suffered even in their sensory life. A gregarious animal, yet kept constantly in isolation, intended by nature to range over vast areas, yet confined to his narrow courtyard, and deprived of opportunity for sexual activity,—he has been forced by a process of education to develop along lines quite opposite to his native characteristics. Nevertheless, I believe that it is very doubtful if it would have been possible by other methods, even, to call forth in the horse the ability to think. Presumably, however, it might be possible, under conditions and with methods of instruction more in accord with the life-needs of the horse, to awaken in a fuller measure those mental activities which would be called into play to meet those needs.

Though our investigations do not give support to the fantastic accounts of animal intelligence given by Brehms, they by no means warrant a return to Descartes and his theory of the animal-machine (as is advocated by a number of over-critical investigators). We cannot deny the validity of conclusions from analogy without denying at the same time the possibility of an animal psychology—indeed of all psychology. And all such conclusions indicate that the lower forms possess the power of sense-perception, that they, like us, presumably have at their disposal certain images, and that their psychic life is to a large extent also constituted of mere image-associations, and that they too, learn by experience. Also that they are susceptible to feelings of pleasure and of pain and also to emotions, as jealousy, fear, etc., though these may be only of the kind which have a direct relation to their life-needs. We are in no position to deny a priori the possibility of traces of conceptual thought in those forms nearest man in the scale—whether living in their natural manner or under artificial conditions. And even less so since the final word has not yet been spoken regarding the nature of conceptual thinking itself. All that is certain is that nothing of the kind has been proven to occur in the lower forms, and that as yet not even a suitable method of discovering its existence has been suggested. But the community of those elementary processes of mental life which we have mentioned above is in itself enough to connect the life of the lower forms with ours, and imposes upon us the duty of regarding them not as objects for exploitation and mistreatment, but as worthy of rational care and affection.

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