In hearing we have the minimum of choice. Sound acts direct upon the great affective centers. We may voluntarily quicken our hearing, or make it dull. But we have really no choice of what we hear. Our will is eliminated. Sound acts direct, almost automatically, upon the affective centers. And we have no power of going forth from the ear. We are always and only recipient.

Nevertheless, sound acts upon us in various ways, according to the four primary poles of consciousness. The singing of birds acts almost entirely upon the centers of the breast. Birds, which live by flight, impelled from the strong conscious-activity of the breast and shoulders, have become for us symbols of the spirit, the upper mode of consciousness. Their legs have become idle, almost insentient twigs. Only the tail flirts from the center of the sensual will.