Shen Buhai insisted that the ruler must be fully informed of the state of his realm, but couldn't afford to get caught up in details and in an ideal situation need listen to no one. Listening to his courtiers might interfere with promotions, and he does not, as Sinologist Herrlee G. Creel says, have the time to do so. The way to see and hear independently is the grouping together of particulars into categories using mechanical or operational method (Fa). On the contrary the ruler's eyes and ears will make him "deaf and blind" (unable to obtain accurate information). Seeing and hearing independently, the ruler is able to make decisions independently, and is, Shen says, able to rule the world thereby.