The Left Hand of Darkness (Hainish Cycle, #4)

by Ursula K. Le Guin

“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.”