Blind Man And Lamp

Somewhere in old days there was a temple in which lived an old monk who had a habit to walk after dinner on the street front.
The street has no lamp, all walkers must walk slow not to hit other persons. Such situation lasted for years.
But one day, when he went to walk, suddenly he saw bright in the street. He stopped and found out the reason.
It was that a blind man hold a lamp walking lonely in the street. He wondered and asked the blind man the reason.
Blind man answered that light is of no use to him but it is useful to others whom when saw light will not hit each other.
Therefore, we can see that we do something which is good to others, but actually it could help us invisibly.
It can be a philosophy that we should try to do something good for others that actually it is good for ourselves too.