As I write this, I have the feeling that my words fail to give force to the idea they seek to express. Indeed, the idea itself is a truth which all peoples readily accept even if they do not act on it. Let me put it differently, then. In order to be at home anywhere in the world I had to forget the things I had been taught to remember. It turned out that my ability to get along with other peoples depended not so much upon my comprehension of the uniqueness of their way of life as my comprehension of the things we had in common. It was important to respect these differences, certainly, but to stop there was like clearing the ground without any idea of what was to be built on it. When you got through comparing notes, you discovered that you were both talking about the same neighborhood, i.e., this planet, and the conditions that made it pleasant or hostile to human life.