There were once three friends. Abe is a Knight, Bill is a Liar, and Carl is neither, having been brought up in a foreign country. (This means he can either lie or tell the truth depending on what he feels like.)

One day, the three were sitting on a bench when the king's herald stopped by to deliver a message to one of them.

He asked the man sitting on the left side of the bench:

"Who's that sitting in the middle? To which the man replied: "Why that's Abe".

He then asked the man in the middle directly:

"What's your name?" and got the answer "My name's Carl."

Confused, he asked the man on the right:

"Who is that sitting in the middle?" and was immediately told: "That's Bill, of course!"

Can you help the king's herald figure out who is who?

A will denote Abe,B will denote Bill,and C will denote Carl.
There are six possible ways they could be sitting.
1:ABC,2:ACB,3:BAC,4:BCA,5:CAB,6:CBA
In 1 and 2,Abe would tell the truth and would either say the middle guy is either Bill or Carl,but not Abe.
Now,there are only four ways,3,4,5,and 6.
In 3 and 5,Abe would say that he is Abe,not Carl.
Now,there are only two ways,4 and 6.
In both cases,the right man is Abe,so the middle man is Bill,leaving 6 as the only possibility.
Carl is on the left,Bill is in the middle,and Abe is on the right.

Posted by Tim Axoy on 2003-03-27 02:47:40