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In "The Wheel Keeps Turning" Silverberg relates the amusing incident that brought about this story's first publication. He happened to show up at editor John W. Campbell's office at the same time as Will F. Jenkins (AKA Murray Leinster). He had this story with him, hoping to sell it. Campbell decided to read it on the spot, and said he liked it except for the ending. He then handed it to Jenkins, who also read it and suggested an alternate conclusion. Campbell then pointed the young RS at a typewriter and asked him to redo the last few paragraphs right then and there. Which he did, resulting in a sale.
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