During the Warring States Period, a man was willing to teach the King of Yan the ways to attain immortality.

The King of Yan was very glad when he heard of this, and quickly sent someone to acknowledge the man as master and learn from him. But before the man he sent had a chance to learn, that man died. The man he sent could only return dejectedly.

At this the King of Yan flew into a rage. He rebuked the man for walking too slowly to get there in time, and ordered to have him killed.

The King of Yan never realized that the man who boasted himself as an immortal was deceiving him, but instead, he blamed the man he sent for walking too slowly.