Vocal music is considered to be the highest, for it is natural; the effect produced by an instrument which is merely a machine cannot be compared with that of the human voice. However perfect strings may be, they cannot make the same impression on the listener as the voice which comes direct from the soul as breath, and has been brought to the surface through the medium of the mind and the vocal organs of the body. When the soul desires to express itself in voice, it first causes an activity in the mind, and the mind, by means of thought, projects finer vibrations in the mental plane. These in due course develop and run as breath through the regions of the abdomen, lungs, mouth, throat and nasal organs, causing air to vibrate all through, until they manifest on the surface as voice.