And it is also necessary to bear in mind that men can only be classified with regard to their emphasis and may belong in one class in regard to one thing and in another class with regard to another, but in any particular place, or at any particular time a man is doing a thing in this world, he is probably for the time being, while he is doing it, doing it as an Inventor (or genius), as an Artist (or organizer), or as a Hewer. Most men, it must be said, settle down in their classifications. They are very apt to decide for life whether they are Inventors or Artists or Hewers. But as has been said before, being on a world and not on a _Titanic_, we have time to think. On what principles could we make out a schedule or inventory of human nature, and decide on world-values in men? When I was a boy I played in the hollow of a great butternut tree--the one my mother was married under. When I was in college I used to go back to it. I used to wonder a little that it was still there. When we had all grown up we all came back and got together under it one happy day and there it still stood, its great arms from out of the sky bent over lovers and over children on its little island, its wide river singing round it, still that glorious old hollow in it, full of dreams and childhood and mystery, and that old sudden sunshine in it through the knots like portholes ... then we stood there all of us together. And the mother watched her daughter married under it. I can remember many days standing beneath it as a small boy (my small insides full of butternuts, a thousand more butternuts up on the tree), and I used to look up in its branches and wonder about it, wonder how it could keep on so with its butternuts and with its leaves, with its winters and with its summers, its cool shadows and sunshines, still being a butternut tree, with that huge hollow in it. I have learned since that if a few ounces or whittlings of wood in a tree are chipped out in a ring around it under the bark, cords of wood in the limbs all up across the sky would die in a week--if one chips out those few little ounces of wood. Cords of wood can be taken out of the inside of the tree and it will not mind. It is that little half-inch rim of the tree where the juice runs up to the sun that makes the tree alive or dead. The part that must be saved first and provided for first is that slippery little shiny streak under the bark. One could dig out a huge brush-heap of roots and the tree would live. One could pick off millions of leaves, could cut cords of branches out of it, or one could make long hollows up to the sun, tubes to the sky out of trees, and they would live, if one still managed to save those little delicate pipe lines for Sap, running up and running down, day and night, night and day, between the light in heaven and the darkness in the ground.