Candle lit bamboo-and-paper lanterns were commonly used in ancient Japan for brightening the evening darkness. And as is the courteous ritual, a friend, one evening, offered just such a lantern to a blind man to carry home with him.
"I do not need a lantern," the blind man remarked. "Darkness or light is all the same to me."
"I know you do not need a lantern to find your way," his friend replied, "but if you don't have one, someone else may run into you. So please take it nonetheless."
Taking the lantern in hand, the blind man started off and before too long he walked squarely into a fellow traveler.
"Look out where you are going!" the blind man barked at the stranger. "Can't you see this lantern?"
"Your candle has burned out, brother," replied the stranger.