"What will happen when my heart stops beating?" Momo asked.
"When that moment comes," said the professor, "time will stop for you as well. Or rather, you will retrace your steps through time, through all the days and nights, months and years of your life, until you go out through the great, round, silver gate you entered by."
"What will I find on the other side?"
"The home of the music you've sometimes faintly heard in the distance, but by then you'll be part of it. You yourself will be a note in its mighty harmonies." Professor Hora looked at Momo searchingly. "But I don't suppose that makes much sense to you, does it?"
"Yes," said Momo, "I think so." Then, recalling her strange progress along Never Lane and the way she'd lived through everything in reverse, she asked, "Are you Death?"
The professor smiled. "If people knew the nature of death," he said after a moment's silence, "they'd cease to be afraid of it. And if they ceased to be afraid of it, no one could rob them of their time any more."
"Why not tell them, then?" Momo suggested.
"I already do," said the professor. "I tell them the meaning of death with every hour I send them, but they refuse to listen. They'd sooner heed those who frighten them. That's another riddle in itself."

(Michael Ende "Momo")