It is a commonplace that the world in which we live has changed more rapidly and more drastically in the last hundred years than perhaps at any other stage of its history. So evident is this fact, and so familiar are the forces that have made for change, that by a curious paradox the mere repetition of arguments about “the shrinking globe,” “the increased speed of travel,” “the growth of communications,” and so on has tended to deaden our awareness of what they mean. From the earliest years of the century, we have become accustomed to hearing that the invention of automobiles, of aircraft, of telephones, and of radio would radically transform our world. If, now, we once more hear the same, or similar statements, made about space travel, ballistic missiles, atomic energy, and television, our immediate reflex is probably a shrug, denoting the understandable feeling that we have met it all before.