[math-fun] undecidability of morality

http://arxiv.org/abs/1411.2842

Logical Limitations to Machine Ethics with Consequences to Lethal Autonomous Weapons

Matthias Englert, Sandra Siebert, Martin Ziegler

--so apparently the idea is, if there is some killer machine, whose construction and programming is known to you, and you have to make a moral decision about what to do about it -- then since you cannot solve the halting problem, you cannot tell what said machine will do, hence deciding which is more moral among two courses of action can be Turing-undecidable. So lethal autonomous weapons will either be unable to function, or will be unable to be moral.