When you are trying to get to Truth Town, you get to No Knaves Town, a city comprised of only Liars and Knights. Each of the three forks leading away from the town (not including the one you came from) leads to a different city.

There are 6 people around. Wanting to know who is what so you can ask them which fork to take, you ask them who is a liar and who is a knight.

A: C would say that B is a liar
B: D would say that C is a knight
C: E would say that F is a liar
D: C would say that A is a knight

Tired of these responses, you ask what fork leads to Truth Town.

E: The left fork leads to Truth Town
F: The middle fork leads to Truth Town

Which fork should you take to get to Truth Town?

assume the answer is the left fork. then E is a knight, F is a liar, C is a knight. for the rest, assume A is a knight, then D is a knight, and B has no status available (contradiction). assume a is a liar, then B is a knight, D is a liar. No contradiction.

assume the answer is the middle fork. then E is a liar, F is a knight, and C is a knight. The rest of the cases are proved above.

assume the answer is the right fork. Then E, F and C are all liars. Assume A a knight, then B is a knight, D is a liar and knight, hence contradicts. If A is a liar, then B is a liar, D is a liar and knight, contradiction.

no conclusion drawn....better try a different approach.

Posted by Terence on 2005-10-08 17:47:11