“On the blank leaf glued to the inner back cover I drew the double curve within the circle, and blacked the yin half of the symbol, then pushed it back to my companion. 'Do you know that sign?'

He looked at it a long time with a strange look, but he said, 'No.'

'It's found on Earth, and on Hain-Davenant, and on Chiffewar. It is yin and yang. Light is the left hand of darkness... how did it go? Light, dark. Fear, courage. Cold, warmth. Female, male. It is yourself, Therem. Both and one. A shadow on snow.' ”