"... how or why, but that Time was evidently a variable. The realm of physics was a madhouse--discreetly so, lest our enemies profit by our knowledge. There is no visual or other subjective means to sense the deceiving change in time-rate, or its illogical effects; we knew, for instance, that you would not see the moon as a solid ring girding a gyroscopic earth, as might seemingly be expected. "Your message of recall was a record, slowed down to be within an intelligible range of fast chatter or slow drawl when you received it. We could have told you to open the envelope at a certain time or distance, but even minutes and miles were critical and"--the pictured features smiled paternally--"we knew your interest in each other might cause a delay, while"--the expression changed to serious sympathy--"we didn't know just when Space-Fear would strike." Carol blushed and laid her cheek against Ken's chest. "They knew everything that would happen, didn't they? They--they _planned_ everything!" He crushed her to him. "Lucky they did, honey. Seems like they've put all their hopes in us." "... imminent war, and what radiation would do to surface life. We could not go with you, nor was there time to build underground installations for surviving more than half a century and emerging to a temporarily unproductive soil. We selected you to inherit the world, and you have had the hopes and prayers of your nation and your people." They sat on a low chest and listened to the psychologist's voice for nearly an hour more. He finished on a message of hope. "You have seen the results of war. With the knowledge and material at hand, and the atmosphere craft waiting at the sealed exit, you can contact what survivors' descendants you may find in hidden corners of the world and lead them to the peaceful glory of Earth's future. "Obviously, life will not visit back and forth between the stars, or even the planets. The laws of Space and Time confine man to one world--but it _can_ be made the best of all possible worlds, free of war within, and free of conquest from without, since the reasons which keep man from visiting other spheres will keep other life from visiting him." The screen faded and was silent, followed by a clear, trilling whistle which swelled in a paean of lilting sound. While Ken squeezed Carol's hand in mounting amazement, the piping strain formed clearly into words-- _With understanding of universal laws, life may do as it wills, go where it wills ... we have come to your planet to help you ... may we?_ The psychologists had not foreseen quite everything....