The Quran asserts the existence of a single and absolute truth that transcends the world; a unique and indivisible being who is independent of the creation. The Quran rejects binary modes of thinking such as the idea of a duality of God by arguing that both good and evil generate from God's creative act. God is a universal god rather than a local, tribal or parochial one; an absolute who integrates all affirmative values and brooks no evil. Ash'ari theology, which dominated Sunni Islam from the tenth to the nineteenth century, insists on ultimate divine transcendence and holds that divine unity is not accessible to human reason. Ash'arism teaches that human knowledge regarding it is limited to what has been revealed through the prophets, and on such paradoxes as God's creation of evil, revelation had to accept "bila kayfa" (without how).