IT doesn’t, in our contemporary world, so much matter where you begin the examination of a subject, so long as you keep on until you get round again to your starting-point. As it were, you start on a sphere, or a cube; you must keep on until you have seen it from all sides. Or if you think of your subject as a stool or table, you must keep on until it has three legs and will stand up, or four legs and won’t tip over too easily. (ABC of Reading)