Prologue Penfield twirled the stem of his port-glass between thumb and finger. “I don’t agree,” he said. “It’s nothing but egocentric vanity to consider our form of life as unique among those on the millions of worlds that must exist.” “How do you know they exist?” said Hodge. “Observation,” said McCall. “The astronomers have proved that other stars beside our sun have planets.” “You’re playing into his hands,” observed Penfield, the heavy eyebrows twitching as he cracked a nut. “The statistical approach is better. Why doesn’t this glass of port suddenly boil and spout all over the ceiling? You’ve never seen a glass of port behave that way, but the molecules that compose it are in constant motion, and any physicist will tell you that there’s no reason why they can’t all decide to move in the same direction at once. There’s only an overwhelming possibility that it won’t happen. To believe that we, on this earth, one of the planets of a minor star, are the only form of intelligent life, is like expecting the port to boil any moment.” “There are a good many possibilities for intelligent life, though,” said McCall. “Some Swede who wrote in German—I think his name was Lundmark—has looked into the list. He says, for instance, that a chlorine-silicon cycle would maintain life quite as well as the oxygen-carbon system this planet has, and there’s no particular reason why nature should favor one form more than the other. Oxygen is a very active element to be floating around free in such quantities as we have it.” “All right,” said Hodge, “can’t it be that the cycle you mention is the normal one, and ours is the eccentricity?” “Look here,” said Penfield, “what in the world is the point you’re making? Pass the port, and let’s review the bidding.” He leaned back in his chair and gazed toward the top of the room, where the carved coats of arms burned dully at the top of the dark panelling. “I don’t mean that everything here is reproduced exactly somewhere else in the universe, with three men named Hodge, McCall and Penfield sitting down to discuss sophomore philosophy after a sound dinner. The fact that we are here and under these circumstances is the sum of all the past history of—” Hodge laughed. “I find the picture of us three as the crown of human history an arresting one,” he said. “You’re confusing two different things. I didn’t say we were elegant creatures, or even desirable ones. But behind us there are certain circumstances, each one of which is as unlikely as the boiling port. For example, the occurrence of such persons as Beethoven, George Washington, and the man who invented the wheel. They are part of our background. On one of the other worlds that started approximately as ours did, they wouldn’t exist, and the world would be altered by that much.”