他在小说中提出了三定律的很多变体。这些对机器人行为准则的修改成为他的很多故事的主线。在《消失无踪》(Little Lost Robot,《我,机械人》中的一个短篇)中为了避免机器人无谓地阻止人类进行低危险性工作,第一定律中的后半部分被去掉了,但是也产生了一些其他的问题[2]。在《机械人之梦》(Robot Dreams,同名小说中的短篇)中,有個機器人因為正子腦出現不尋常碎形結構而進入無意識與夢境狀態;夢中第一及第二法則不復存在,而第三法則被修改為「機器人必須保護自身的存在」[3]。在《机器人与帝国》中,有些机器人因為系统中「人类的定义」被修改(说话没有该星球的口音就不是人类)而攻击人类[4]。在1999年上映的科幻电影《双百人》(Bicentennial Man,原为短篇小說,后改编为中篇小说《正子人》)中,一个机器人为了成为人,将自己的机械部分逐步替换成组织,并且在最后用自己的贡献和牺牲换来了人类的认同和保护机器人的法律的产生。[5]
^Isaac Asimov. BBC. [11 November 2010]. (原始内容存档于2010-01-10).
^ 2.02.1Asimov, Isaac. Runaround. I, Robot The Isaac Asimov Collection. New York City: Doubleday. 1950: 40. ISBN 978-0-385-42304-5(英语). This is an exact transcription of the laws. They also appear in the front of the book, and in both places there is no "to" in the 2nd law.
^Asimov, Isaac. Robot Dreams. 1986 [11 November 2010]. “But you quote it in incomplete fashion. The Third Law is ‘A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.’ ” “Yes, Dr. Calvin. That is the Third Law in reality, but in my dream, the Law ended with the word ‘existence’. There was no mention of the First or Second Law.”
^Frank Pasquale. 二十一世紀機器人新律:如何打造有AI參與的理想社會?. 由李, 姿儀翻译. 台灣: 左岸文化. 2023-03-08. ISBN 9786267209271.
^Frank Pasquale. New Laws of Robotics: Defending Human Expertise in the Age of AI. Belknap Press: An Imprint of Harvard University Press. 2020-10-27. ISBN 978-0674975224.
^The Three Laws of Robotics Have Failed the Robots. Mind Matters. 2019-09-28 [2022-12-07]. (原始内容存档于2022-12-07). Chris Stokes, a philosopher at Wuhan University in China, says, “Many computer engineers use the three laws as a tool for how they think about programming.” But the trouble is, they don’t work. He explains in an open-access paper:The First Law fails because of ambiguity in language, and because of complicated ethical problems that are too complex to have a simple yes or no answer.The Second Law fails because of the unethical nature of having a law that requires sentient beings to remain as slaves.The Third Law fails because it results in a permanent social stratification, with the vast amount of potential exploitation built into this system of laws.