"Well, I still have some power left," he snarled. "And I say that my son shall go to Unseen University and wear the Archchancellor's hat and the wizards of the world shall bow to him! And he shall show them what lies in their deepest hearts. Their craven, greedy hearts. He'll show the world its true destiny, and there will be no magic greater than his."
NO. And the strange thing about the quiet way Death spoke the word was this: it was louder than the roaring of the storm. It jerked Ipslore back to a momentary sanity.
Ipslore rocked back and forth uncertainty. "What?" he said.
I SAID NO. NOTHING IS FINAL. NOTHING IS ABSOLUTE, EXCEPT ME, OF COURSE. SUCH TINKERING WITH DESTINY COULD MEAN THE DOWNFALL OF THE WORLD. THERE MUST BE A CHANCE, HOWEVER SMALL. THE LAWYERS OF FATE DEMAND A LOOPHOLE IN EVERY PROPHECY.
Ipslore stared at Death's implacable face.
"I must give them a chance?"
YES.
Terry Pratchett, Sourcery