We never see a tree except through the image that we have of it, the concept of that tree; but the concept, the knowledge, the experience, is entirely different from the actual tree. Look at a tree and you will find how extraordinarily difficult it is to see it completely, so that no image, no screen, comes between the seeing and the actual fact. By completely I mean with the totality of your mind and heart, not a fragment of it.
He had, they said, tasted in succession all the apples of the tree of knowledge, and, whether from hunger or disgust, had ended by tasting the forbidden fruit.