Wikipedia cites extensions by other authors to the canonical "Three laws" as follows

There are two Fourth Laws written by authors other than Asimov. The 1974 Lyuben Dilov novel Icarus's Way (a.k.a. The Trip of Icarus) introduced a Fourth Law of robotics:

A robot must establish its identity as a robot in all cases.

Dilov gives reasons for the fourth safeguard in this way: "The last Law has put an end to the expensive aberrations of designers to give psychorobots as humanlike a form as possible. And to the resulting misunderstandings..."[29]

For the 1986 tribute anthology Foundation's Friends Harry Harrison wrote a story entitled, "The Fourth Law of Robotics". This Fourth Law states:

A robot must reproduce. As long as such reproduction does not
interfere with the First or Second or Third Law.

In the book a robot rights activist, in an attempt to liberate robots, builds several equipped with this Fourth Law. The robots accomplish the task laid out in this version of the Fourth Law by building new robots who view their creator robots as parental figures.[30]

A fifth law was introduced by Nikola Kesarovski in his short story "The Fifth Law of Robotics". This fifth law says:

A robot must know it is a robot.

My interest is primarily focused on the first of the 4th laws (4a if you prefer) and the 5th law.

Was Asimov made aware of these extensions during his lifetime and is there any documented evidence to support any opinion he had on them?

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    You neglect the Zeroth law, which Asimov supplied. A robot may not harm humanity, or, by inaction, allow humanity to come to harm – geoffc Aug 2 '12 at 20:45
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    Asimov supplied that rule himself so it is already valid – Merlin Aug 2 '12 at 21:02
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    I am not sure how @geoffc comment is in scope of this question. The first three rules are accepted, this is a question about the 4th and 5th. – Ashterothi Aug 2 '12 at 22:51
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    @Pyrodante Mostly because the issue starts with laws other than the first three, and there is an other than the first three not mentioned. – geoffc Aug 3 '12 at 1:12
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    @geoffc I neglected nothing. This question relates directly to "4th and 5th" extensions of what is commonly referred to as "the three laws" (regardless of whether one includes zeroeth or not). – Merlin Aug 3 '12 at 10:09
up vote 9 down vote accepted

Asimov repeatedly wrote in his essays and autobiography that his Three Laws of Robotics became a basic concept of science fiction, and were used by other authors. However, he makes it clear that no other author ever quoted the Three Laws, only ever assumed them implicitly - which is how Asimov preferred it. Other authors could assume that robots would behave according to Asimov's Three Laws of Robotics, but only Asimov could quote them.

However, he never mentions any additional laws (except his own Zeroth Law). Given his attitude that he preferred for other authors not to quote his Three Laws, but only assume them, I think he would NOT give his official approval to any additions to his Laws.

  • any documented evidence to support this view – Merlin Aug 3 '12 at 22:08
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    "Now it is understood that science fiction writers generally have created a pool of ideas that form a common stock into which all writers can dip. For that reason, I have never objected to other writers who have used robots that obey the Three Laws. [...] However, I have firmly resisted the actual quotation of the Three Laws by any other writer. Take the Laws for granted, is my attitude in this matter, but don't recite them. The concepts are everyone's but the words are mine." 'My Robots', an essay in the collection 'Robot Visions'. Other writers could assume the Laws, not quote them. – Algernon_Asimov Aug 3 '12 at 23:46
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    I just read the Robot City series. A series supported by Azimov. In the foreword of the first novel "Odyssey" he mentions (and I quote): " is just as well if I relax my rules and allow others to make use of them (the Laws) and reinvigorate them." – Vincent Vancalbergh Sep 18 '13 at 11:45
  • @VincentVancalbergh: be careful, Asimov didn't like when people spelt his name wrong. By Robot City series, do you mean the Caliban trilogy by Roger MacBride Allen? – b_jonas Jan 27 '14 at 9:29
  • @b_jonas, No I mean's_Robot_City. And I deeply regret misspelling his name. Unfortunately, I can't edit the comment anymore :( – Vincent Vancalbergh Jan 27 '14 at 10:06

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