RC Macaulay wrote:
In west Texas there lived two tribes of natives. One tribe had red feet and never told lies. One tribe had green feet and never told the truth.
Question>> If you were traveling in the area during the darkest night and encountered a tribe in the dark..
Phrased correctly, what single question could be posed to the tribe in the darkest night that would be answered in such a way that you could determine if they were lying or telling the truth?
There must be something missing. As stated, any question with a well-known answer fits the bill.
"Is it dark tonight?" --> truthful tribe: "yes", lying tribe: "no"
"What color would a red-footed native tell me his feet were?" -->
truthful tribe answers "red", lying tribe answers "green" (or any other non-red color).
Perhaps you meant to say "one tribe had red feet, the other had green; one tribe told the truth, the other lied" and then, without specifying which foot color went with truthfullness, ask how you could determine the color of their feet with a single yes-or-no question (again, on a dark night).
Note, though, that in this case you can't determine whether they're a liar or truth-teller with the same, single question, since one question elicits just one bit of information, and the color/truthfullness mapping requires one bit itself, and which kind of native you're talking to requires a second bit.
