It was a couple of pages, dated like a diary, hastily folded and stashed in a book that had been gathering dust on the shelf for the past decade.

The first sentence, followed by its simple message, jumped out at Natalie. Her heart beat in her throat as she ran a finger over the words. She recognised the untidy scribbled handwriting of Walter, the head librarian.

The global vote on the Forgetting will start soon. If even one remembers, the drive to scrub the incident from the pages of history will fail. We do not need to remember what we did in those three days, in our drive to establish control over memory. I believe all will come to see the wisdom of forgetting...

She turned the page.

The vote has succeeded. By law, every government must ensure that all forget. Soon, we can begin to heal as a people, to move forward...

Walter's dry cough made Natalie drop the book on her foot. She ignored the pain as she stared at him. His bright blue eyes were narrowed in a rare expression of annoyance.

"Natalie," he said, as he picked up the book and gripped it against his chest. "You should not have read that."

"I forgot as well, didn't I?" she whispered. "We all did. What does it refer to?"

"Well, I can hardly tell you, can I?" he said drily. "I don't remember, either."

He put the book back on the shelf, taking the pages out and slipping it in his pocket. A vein was jumping in his forehead as he avoided her gaze.

"You're lying. You do remember. Not everyone forgot, did they?" she demanded.

Walter felt deeply tired as he stared at the girl, her face flushed red in anger. No more than a child when everyone forgot. She would never understand. Almost no one would. Except the historians, who had let it happen. Who had been allowed - cursed - to remember, so as never to repeat their mistake. On impulse, he decided to explain. Breaking every rule that had been set out to them. But she was his granddaughter, after all.

"Gaining the perfect memory. A grand experiment," he said, closing his eyes as he remembered.

"Experiment?" she began, incredulous. "What are talking about? Everyone's always been able to -"

He held up a finger and she fell silent. "Grand, and dangerous. Remember everything perfectly, so nothing would ever be lost. And we got there eventually, did we not? Yes, the scientists had been mostly right. It could be done. They told us how, you know."

He lapsed into silence as he smiled sadly and took out the pages, reading his own diary notes.

"They preached caution, they did. They told us not to start the process of trying to absorb a piece of knowledge permanently prematurely. Told us of the possible side effects. Of wiping out knowledge on a global scale. But did we listen..."

He took out a book from a shelf behind him and flipped it open for Natalie to see. It was blank. The title on the front of the book was barely decipherable: Macbeth.

"What is it?" she asked curiously, flipping through it again. Nothing but the faint title.

"Precisely," Walter sighed, and leaned back in his armchair. "What is it? What is Einstein's theory of relativity, that we see references in the snatches of phrases that remain of his work? What is evolution? What is Macbeth, and the Spear who wrote it? For that is all that we see remains of his name..."

"You're not making any sense, grandpa," Natalie complained.

"It doesn't make sense because we chose to forget what we did, child," he muttered faintly as he started to fall asleep, the blank book cradled in his lap. "That we wiped out the words and the knowledge from collective memory as we tried to absorb them. And when we perfected the process, it was gone. All gone, and forgotten. Better not to remember...I only wish I could...forget..."

He fell silent as he sank into a troubled sleep. Natalie tiptoed out of the library, feeling worried. Sometimes, she felt like he was becoming hazier in his old age, was losing his grip on reality. But that didn't happen, did it? She'd heard people whisper of the possibility, but dismissed it firmly from her mind. There was no proof for something like that. Her grandpa would be fine.