But no philosophy, however workable, however noble, can hope to convert everyone. There always remains a hard core of men who feel that "the old way is the best way". In this case, it was the men whose lives had been based on cunning, deceit, and treachery. One of these men, a brilliant, but warped genius, named Sator, had built the first spaceship, and he and his men had fled Nansal to set up their own government and free themselves from the persecution they believed they suffered at the hands of the believers of Norus. They fled to the second planet, where the ship crashed and the builder, Sator, was killed. For hundreds of years, nothing was heard of the emigrants, and the people of Nansal believed them dead. Nansal was at peace. But the Satorians managed to live on the alien world, and they built a civilization there, a civilization based on an entirely different system. It was a system of cunning. To them, cunning was right. The man who could plot most cunningly, gain his ends by deceiving his friends best, was the man who most deserved to live. There were a few restrictions; they had loyalty, for one thing--loyalty to their country and their world. In time, the Satorians rediscovered the space drive, but by this time, living on the new planet had changed them physically. They were somewhat smaller than the Nansalians, and lighter in color, for their world was always sunless. The warm rays of the sun had tanned the skins of the Nansalians to a darker color. When the Satorians first came to Nansal, it was presumably in peace. After so many hundreds of years without war, the Nansalians accepted them, and trade treaties were signed. For years, the Satorians traded peacefully. In the meantime, Satorian spies were working to find the strengths and weaknesses of Nansal, searching to discover their secret weapons and processes, if any. And they rigorously guarded their own secrets. They refused to disclose the secrets of the magnetic beam and the magnetic space drive. Finally, there were a few of the more suspicious Nansalians who realized the danger in such a situation. There were three men, students in one of the great scientific schools of Nansal, who realized that the situation should be studied. There was no law prohibiting the men of Nansal from going to Sator, but it seemed that Nature had raised a more impenetrable barrier. All Nansalians who went to Sator died of a mysterious disease. A method was found whereby a man's body could be sterilized, bacteriologically speaking, so he could not spread the disease, and this was used on all Satorians entering Nansal. But you can't sterilize a whole planet. Nansalians could not go to Sator.