On Gethen, there are two dominant religions. The first is Yomeshta, which follows the teaching of Meshe and resembles a Judeo-Christian religion. The second is Handdara, a spiritual practice closer to Taoism. Yomeshta is centred around the idea of light, and unity. In contrast, Handdara is interested in the interaction of light and dark, and in the way opposites can come together and complement each other. Although both religions are described in-depth, the novel more closely aligns itself with the Handdara philosophy. Gethen is a world of both light and dark. Its people are both men and women. As a result, the Handdara interest in opposites that clarify or balance each other better describes the planet and its inhabitants than does the pure, uncomplicated light of Yomeshta. Handdara is a religion of dualism — the self and the other, the known and the unknown, the light and the dark. This explicitly reflects Gethenian sexuality — every person has a dual identity and is both a man and a woman. In contrast, the Yomeshta say “man’s singularity is his divinity,” however the narrative makes it clear that Gethenian’s divinity comes from their duality. Even the title of the book is a celebration of duality; it comes from a Handdarata proverb, which goes, “Light is the left hand of darkness / and darkness the right hand of light. / Two are one, life and death, lying / together like lovers in kemmer, / like hands joined together, / like the end and the way.” Yomeshta attempts to celebrate only life, but Handdara understands that for life to be properly celebrated, it must be set up in contrast to its opposite, death. Ai compares Handdara, and the Gethenians themselves, to the Terran concept of yin and yang. He says, “Light, dark. Fear, courage. Cold, warmth. Female, male,” each pair of opposites exists within each resident of Gethen.