When a man is looking at one side he is unconscious of the other. This shows that the faculty of seeing and being conscious of what one sees can only engage itself fully with one thing at a time. A conception of musical sound which has been held for a long time in the East, and which today is recognized by scientists in the West, is that man's ears can only hear fully one sound at a time, not two or three. This indicates that each sense is capable of looking at one side only; the other is absent from the consciousness; and in order to see a particular side one has to turn one's face to it. In other words, one has to expose one's faculty of seeing to that side.