Campbell said: “Look, Asimov, in working this out, you have to realize that there are three rules that robots have to follow. In the first place, they can’t do any harm to human beings; in the second place, they have to obey orders without doing harm; in the third, they have to protect themselves, without doing harm or proving disobedient.”
Asimov would take up these operating principles proposed by Campbell and give them formal expression in his stories as the Three Laws of Robotics.