Nasreddin was cutting a branch of a tree in his garden. While he was sawing, another man passed in the street. He stopped and said, 'Excuse me, but if you continue to saw that branch like that, you will fall down with it.' He said this because Nasreddin was sitting on the branch and cutting it at a place between himself and the trunk of the tree.
Nasreddin said nothing. He thought, 'This is some foolish person who has no work to do and goes about telling other people what to do and what not to do.'
The man continued on his way.
Of course, after a few minutes, the branch fell and Nasreddin fell with it.
'My God!' he cried. 'That man knows the future!' and he ran after him to ask how long he was going to live. But the man had gone.