A polytheistic religion that was formed from a variety of different religious practices. In Hinduism, salvation is achieved through a spiritual oneness of the soul, atman, with the ultimate reality of the universe, Brahma. To achieve this goal, the soul must obtain moksha, or liberation from the samsara, the endless cycle of birth, death, and rebirth. As a result of these basic teachings, Hindus believe in reincarnation, which is influenced by karma (material actions resulting from the consequences of previous actions), and dharma (fulfilling one's duty in life). Because all forms of animal life possess souls, Hindus believe in ahimsa, or that all life is sacred. and should not be harmed. In fact, one animal which Hindus consider to be extremely sacred is the cow. The peaceful and contented existence of cows is considered virtuous by Hindus and would represent a rewarding reincarnation for a soul. For this reason, most Hindus are vegetarians so that they do not harm other living beings. The belief in reincarnation, karma, and dharma also provides the religious justification for the existence of the rigid social structure known as the Caste System.