According to the standpoint of the Sufi, both are right, and yet both are wrong. For he applies the law of vibration in his understanding of the world, that each note has its finish at the octave. So there are an ascending and a descending scale. Each strong accent in anything has its weak part to balance it. The sun rises as well as sets and the new moon develops to the full and wanes until it is again new. Each wave of the sea which rises high is drawn back and each helpless child is again helpless when old. This is the nature of evolution. A certain direction of life develops for a certain period and before it has fallen back another direction of life begins to evolve.