"The world did not exist from eternity. It has come into existence after not being. Everything in it comes into existence, and then perishes, and it is obvious that this principle of transitoriness applies to the world as a whole. One has to seek for the cause of these changes, and, ultimately, for the primal cause of existence of world. It is impossible to think that certain portion of the world is quiescent, and is the source of the movement and of the changes in the other portion, because if the world is ultimately one, there cannot exist such a duality. Going up the chain of causation, one