As you know Akbar considered Birbal the most intelligent person of his kingdom. Once a sculptor challenged Baadshaah Akbar that he would show three idols to him, which would look exactly like each other to his courtiers and they would have to rate them good, ok and bad. Akbar agreed.
All the courtiers tried to rate them but failed, because they were so alike that they did not know how to rate them. Now it was Birbal's turn. He noticed a small hole in the ears of the idols. Birbal got curious, so he took three wires and inserted them in those holes.
In the case of the first idol the wire came out from the other ear. In the second case idol, it came out of the mouth; but in the case of the third idol, it remained inside. He got the answer and he rated the third idol as good, first idol ok and the second idol bad.
The sculptor could not understand what was the basis of rating the idols. He asked Birbal that how was he so sure? Birbal said - ''The third idol (from whose ear the wire remained inside) did not tell others what somebody else had told it, that is why it was good. The first idol was OK (from whose ear the wire came out from the other ear) because it did not remember or tell others what somebody had told it. But the third idol (from whose ear the wire came out from the mouth) remembered everything and gave out the secret what was told to it to others.'
The sculptor was speechless and Akbar was very happy. He gave lots of reward to Birbal.