Chapter eight, Gods of India, begins with the Indus Valley culture and the pantheon of nature gods introduced by Aryan overlords. These gods are described by the Vedas, the oldest holy books in Hinduism, and perhaps the World. Worship of these Vedic gods was through sacrifice rituals, as was common for all religions in the time before the current era. During the final centuries of the previous era and the early centuries of the current era, Indian philosophers transformed the sacrifice-oriented Vedic worship into profoundly philosophical modern Hinduism through a series of texts known as the Upanishads. They also consolidated the Vedic gods into the Hindu Trimurti of Brahma, Vishnu, and Shiva as the gods of creation, preservation, and destruction, respectively, consistent with the Hindu view of the cyclic nature of reality.