“She closed her eyes, and as had been her habit over these past couple of days, she began to imagine possible past histories and what she might have done to change them into the new one in which she lived, either inadvertently, or out of a misguided attempt to play God and make the world a better place, or, worse, with malice aforethought. Any time she spent in the past would have been clipped out of history, as neatly as if it had never happened, because it hadn't happened.”
Book:Version Control