The mystery, he thought, the explanation, he means. Of a secret. A sacred secret. We shall not die. The reflexions shall leave. And it will happen fast. We shall all be changed, and by that he means reversed back, suddenly. In the twinkling of an eye. Because we are fucking backward right now, I guess, every one of us, everyone and every damn thing, and distance, and even time. But how long, he thought, when a print is being made, a contact print, when the photographer discovers he's got the negative reversed, how long does it take to flip it? To reverse it again so it's like it's supposed to be? A fraction of a second.

Chapter 12 (p. 222) - A Scanner Darkly (1977)