But the two qualifications of the teacher already named will not alone suffice. I have known persons who were sympathetically imaginative, and who could not be denied to possess large intellectual wealth, who still failed as teachers. One needs a third something, the power to invigorate life through learning. We do not always notice how knowledge naturally buffets. It is offensive stuff, and makes young and wholesome minds rebel. And well it may; for when we learn anything, we are obliged to break up the world, inspect it piecemeal, and let our minds seize it bit by bit. Now about a fragment there is always something repulsive. Any one who is normally constituted must draw back in horror, feeling that what is brought him has little to do with the beautiful world he has known. Where was there ever a healthy child who did not hate the multiplication table? A boy who did not detest such abstractions as seven times eight would hardly be worth educating. By no ingenuity can we relieve knowledge of this unfortunate peculiarity. It must be taken in disjointed portions. That is the way attention is made. In consequence each of us must be to some extent a specialist, devoting himself to certain sides of the world and neglecting others quite as important. These are the conditions under which we imperfect creatures work. Our sight is not world-wide.