The Ghost Writer by Philip Roth:
This was the lesson that on the journey home she came to believe she had the power to teach. But only if she were believed to be dead. Were Het Achterhuis known to be the work of a living writer, it would never be more than it was: a young teenager’s diary of her trying years in hiding during the German occupation of Holland, something boys and girls could read in bed at night along with the adventures of the Swiss Family Robinson. But dead she had something more to offer than amusement for ages 10-15; dead she had written, without meaning to or trying to, a book with the force of a masterpiece to make people finally see.
And when people had finally seen? When they had learned what she had the power to teach them, what then? Would suffering come to mean something new to them? Could she actually make them humane creatures for any longer than the few hours t would take to read her diary through? In her room at Athene—after hiding in her dresser the three copies of Het Achterhuis—she thought more calmly about her readers-to-be than she had while pretending to be one of them on the stirring bus ride through the lightning storm. She was not, after all, the fifteen-year-old who could, while hiding from a holocaust, tell Kitty, I still believe that people are really good at heart. Her youthful ideals had suffered no less than she had in the windowless freight car from Westerbok and in the barracks at Auschwitz and on the Belsen heath. She had not come to hate the human race for what it was—what could it be but what it was?—but she did not feel seemly any more singing its praises.