Campbell told him: “Asimov, when you have trouble with the beginning of a story, that is because you are starting in the wrong place, and almost certainly too soon. Pick out a later point in the story, and begin again.”
This most certainly was not Techno Age storywriting advice. That would have been to begin at the beginning, and then to go on until the end, telling everything that happened along the way. This was fundamental modern science fiction writing advice—to start a story as late as possible and tell no more than was necessary.