sir, again, how does that equate with this:Nangaku then says, “"I'm polishing this to make a mirror." We should be clear about the meaning of these words. There is definitely a reason to “polish to make a mirror,” in which the Buddhist truths are always present and the realized universe is present, and it is not some empty endeavor. Although tiles are tiles and mirrors are mirrors, we should know that when we are striving to master the principle of “polishing,” we shall find that this polishing possesses a limitless abundance of distinguishing features. It may be that even the “eternal mirror” and the “clear mirror” are made mirrors by polishing a tile. If we do not realize that mirrors come from “polishing a tile,” then the buddhas and ancestors have nothing to say, do not open their mouths, and we do not perceive the exhaling of the buddhas and ancestors.
It is basic Mahayana Wisdom that the “eternal mirror” and the “clear mirror” cannot be made or polished (and are truly thus "non mirrors"), so we sit diligently polishing and making what cannot be polished or made. Very simple.