in æsthetic bearing by continued exercise or hearing of them. This should be made the subject of scientific research. But already in every factory, foundry, and boiler shop is to be found what amounts to experimental confirmation of our theory.
Now for the pleasures of hearing. We have confessed to strong sensuous pleasure from music, but I suspect that the ordinary delights of music originate in the sensations accompanying the movements by which we make vocal sounds, rather than in the ear. We express emotion pre-eminently by the voice. The emotions awakened by music are those expressed by the voice. Whatever the final seat of these emotions, there is a deep and strong association from the ear through the voice to this seat. The crude musician takes more delight in the act of shouting than in the noise he makes. And the cultured musician seems to gain in aesthetic delight rather by expansion of intellectual associations than from new sensations rising from the ear. We may presently find reasons for connecting all our emotions peculiarly with certain primary functions of the body. Among others, with the movements of breathing — abdominal, thoracic, and the aspirative movements in the throat, mouth, lips, and nose. Such emotions as are seated in this class of organs will plainly have connections with those expressed by the voice, and through the voice with the aesthetics of hearing. But these would only make plainer that the great majority of the delights of sounds are not sensations from the ear. Again, as with color, we discover how difficult it is from introspection alone to decide between our two modes of pleasure — whether some of the pleasures of hearing are or are not sensations. To me it is a matter of doubt if there are now, or ever were, any pleasure nerves in the auditory organs. Whether there are such is a matter for exact investigation. If there are such the general nature of the pleasures arising from them, and of the stimulation which may affect them, are sufficiently indicated by what we have already said of the like class under vision. All other pleasures of hearing than these possible sensations we shall class as associations.
Constancy of psychic reaction to apparently constant condi-
