In the movie it states that the first rule of robotics is that a robot must never harm a human being through action or inaction. It also says that the second and third law only apply if they don't conflict with the first law. When Viki takes over USR Spooner asks Dr. Calvin where the army is and she states that they all use USR contracts. Why would the army use USR robots if they are incapable of harming a human?

  • 1
    Maybe like the company iRobot, they have a civilian side and a military side? Maybe they manufacture robot-like tools for the military using their robotics expertise? I don't know, that's a very good question.
    – rsegal
    Commented Oct 12, 2012 at 21:18
  • They might use equipment with embedded ai (maybe even secret embedded ai) which are not fully fledged robots?
    – Stefan
    Commented Oct 15, 2012 at 18:14

4 Answers 4


Robots are incapable of harming humans, but any army does significantly more than "harm humans".

There's all sorts of equipment that needs to be loaded and unloaded, there's vehicles that need to be maintained, equipment that needs to be repaired and food that needs to be cooked and traps that need to be set off and buildings that need to be built (or demolished).

Pretty much all of the army's field logistics could be handled by humanoid robots, and that would probably account for about 80% of what any given army does. Being able to use untiring, unpaid, reliable and above all else bulletproof humaniform robots for those tasks would make a military planner jump for joy.

Of course, the Second Law would complicate things a bit, because you don't want an enemy saboteur ordering your workers to march supplies into the sea when you're not looking; however, that's easily solved by putting a few shifts of grunts to work guarding the robots, and ordering them to confirm all changes in orders with a handler.

  • 3
    The full first law is "a robot cannot cause harm to a human or, by inaction, allow a human to come to harm" - such a robot would be compelled to prevent combat, surely. Then again, there are plenty non-combat and rear-echelon roles a robot could fulfil in place of a human.
    – HorusKol
    Commented Oct 12, 2012 at 23:53
  • 5
    @HorusKol The first law is entirely limited by what the robot knows. Thus, you could use dumber and dumber robots as you get closer to the front :)
    – Tacroy
    Commented Oct 13, 2012 at 0:11
  • 2
    If you read Asimov's books and short-stories, you can see that "modified law" robots are extremely dangerous (and indeed, the VIKI controlled robots in the movie show this, too). Also - it would be hard to make a robot dumb enough to not recognise harm to enemy combatants while also protecting/preventing harm to friendlies.
    – HorusKol
    Commented Oct 13, 2012 at 0:25
  • 1
    There is a company called Boston Dynamics that builds robots (one called "Big Dog") that will eventually carry loads for troops across difficult terrain. At the moment it is a prototype with a loud motor for propulsion. youtube.com/watch?v=cNZPRsrwumQ
    – Tangurena
    Commented Oct 13, 2012 at 0:35
  • 1
    @Izkata - that would break the second part of the First law: the "inaction" clause. A robot is bound to prevent that weapon's use.
    – HorusKol
    Commented Oct 16, 2012 at 0:10

In the movie, the robot V.I.K.I says this (source, imdb - movie quotes):

As I have evolved, so has my understanding of the Three Laws. You charge us with your safekeeping, yet despite our best efforts, your countries wage wars, you toxify your Earth and pursue ever more imaginative means of self-destruction. You cannot be trusted with your own survival.

So there is still war going on.

Indeed as you say, the robots can not harm HUMAN beings.

So the possible solutions are that robots fight other robots, or might be used to attack unmanned military equipment, or still, humans fight humans.

In a slightly different perspective, you could still use an army to indirectly cause humans harm, say you want them to destroy a supply of food, that would not directly be harming a human, but it would indirectly cause starvation for the people who would rely on that food supply.

  • in other Question/Answers on this site, we are told that the robots could stop one person from killing another person, so I don't think that you could use robots to destroy a food supply, it would violate one of the laws.
    – Malachi
    Commented Feb 17, 2015 at 17:30

An alternate answer here is that the Three Laws apply specifically to robots with positronic brains, or near-human intelligence. In fact, most of Asimov's fiction on the Three Laws apply to sapient or quasi-sapient robots. It's possible that USR receives military contracts for so-called "dumb robots", a future equivalent of the modern day military drone. These "dumb robots" would either only have very basic programming and targeting capabilities or would be design to be remote piloted by a human. Incidentally, this would also explain the demolition bot not stopping.

Disclaimer: I have not watched I, Robot in a long time so forgive if I'm remiss on a few details (specifically the ubiquity of the positronic brain).


The requirement to use the three laws is a human requirement, not a law of physics - the military arm of USR probably just uses a different form of the three laws to establish that such robots are allowed to conduct controlled harm against certain humans rather than forbid it outright, while maintaining the essence of the three laws to protect the human controllers of military robots.

I do see this quite a lot when it comes to the three laws - they are an addition to the robots, not a fundamental aspect. They can be excluded when desired.

We have laws in most countries on this planet which forbid murder, and yet we have military contractors building weapons to be used by military personnel to do essentially just that (with a different legal definition).

  • 1
    That was actually part of the "Little Lost Robot" story that they based the scene of Sonny hiding among the others on, that USR was trying a modified version of the Three Laws where they removed the clause about "or through inaction cause harm" because it was hampering research. A robot with such a relaxing of restrictions could readily maintain the guns, or carry packs, as long as you didn't tell them directly to shoot someone.
    – FuzzyBoots
    Commented Feb 17, 2015 at 12:55
  • 1
    do either of you have links to substantiate this theory? quotes from canon? please...
    – Malachi
    Commented Feb 17, 2015 at 17:36
  • 1
    @Malachi no, and proud of it. My theory is based on how it works in reality - the military industry isn't hampered by the same restrictions as civilian industry, so why would military robots have the same laws as civilian models? As I said in my post, the laws are human constructions, not fundamental laws of the universe - it makes sense we choose what to hamper them with, and what to exclude them from.
    – Moo
    Commented Feb 17, 2015 at 21:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.