In the salutation made by putting one knee on the ground, the knee resting on the ground expresses readiness to receive the command and the knee that is up is ready to go forward to carry it out. But besides their psychological influences, different manners of courtesy have been the outcome of human progress in the direction of refinement. And yet progress in every direction is like a wave in the sea -- it rises and it falls. So it is with manners. This time seems to be the time when the wave is coming back. However, doing a thing is one thing, and understanding it is another thing. Whether one does a certain thing or does not do it, that is another question, but in the understanding of all things lies the purpose of life.