Heaven and earth are in contact and combine their influences, producing a time of universal flowering and prosperity. This stream of energy must be regulated by the ruler of men. It is done by a process of division. Thus men divide the uniform flow of time into the seasons, according to the succession of natural phenomena, and mark off infinite space by the points of the compass. In this way nature in its overwhelming profusion of phenomena is bounded and controlled. One the other hand, nature must be furthered in her productiveness. This is done by adjusting the products to the right time and the right place, which increases the natural yield. This controlling and furthering activity of man in his relation to nature is the work on nature that rewards him.