Logic Exercises (for Freshman Composition)

The Three Laws of Robotics

1. A robot may not harm a human being, or through inaction, allow a human being to come to harm.
2. A robot must follow the orders given it by a human being except where such orders would conflict with the First Law.
3. A robot must protect its own existence so long as such protection does not conflict with the First or Second Laws.
4. -- Handbook of Robotics, 56th Edition, 2058 AD
(via the science-fiction author Isaac Asimov)

You are a robot, programmed according to the Laws of Robotics, as stated above.  On a piece of scratch paper, sketch out your logical reactions to the following situations:
1. A huge tree is about to fall on a child playing on the other side of the street.  A crossing guard is holding a "Stop" sign at you, preventing you from getting to the child.  What do you do?  Explain every step of your reasoning.
2. The situation is the same as in #1, except now you realize that the tree will crush you if you try to save the child.  In fact, you'll be crushed before you can even get to the child.  Based on these rules, what do you do?
3. In a completely different situation, your owner orders you to jump in front of a speeding bus.
4. The situation is the same as in #3, except now your owner's ex-girlfriend is on the bus, you are a huge industrial robot with glittering tritanium armor plates, and you weigh twice as much as the bus does.
5. Same as #4, except now the bus is about to run over your owner.
6. Asimov eventually prefixed a Zeroth Law:  "A robot may not injure humanity or, through inaction, allow humanity to come to harm," and the other laws were modified to preclude violating it.  Describe a scenario in which a robot might encounter difficulty determining whether this law applies.