Incorporated in this rich literature is a complex cosmology. Hindus believe that the universe is a great, enclosed sphere, a cosmic egg, within which are numerous concentric heavens, hells, oceans, and continents, with India at the center. They believe that time is both degenerative—going from the golden age, or Krita Yuga, through two intermediate periods of decreasing goodness, to the present age, or Kali Yuga—and cyclic: At the end of each Kali Yuga, the universe is destroyed by fire and flood, and a new golden age begins. Human life, too, is cyclic: After death, the soul leaves the body and is reborn in the body of another person, animal, vegetable, or mineral. This condition of endless entanglement in activity and rebirth is called samsara (see Transmigration). The precise quality of the new birth is determined by the accumulated merit and demerit that result from all the actions, or karma, that the soul has committed in its past life or lives. All Hindus believe that karma accrues in this way; they also believe, however, that it can be counteracted by expiations and rituals, by “working out” through punishment or reward, and by achieving release (moksha) from the entire process of samsarathrough the renunciation of all worldly desires.
Hindus may thus be divided into two groups: those who seek the sacred and profane rewards of this world (health, wealth, children, and a good rebirth), and those who seek release from the world. The principles of the first way of life were drawn from the Vedas and are represented today in temple Hinduism and in the religion of Brahmans and the caste system. The second way, which is prescribed in the Upanishads, is represented not only in the cults of renunciation (sannyasa) but also in the ideological ideals of most Hindus.
The worldly aspect of Hinduism originally had three Vedas, three classes of society (varnas), three stages of life (ashramas), and three “goals of a man” (purusharthas), the goals or needs of women being seldom discussed in the ancient texts. To the first three Vedas was added the Atharva-Veda. The first three classes (Brahman, or priestly; Kshatriya, or warrior; and Vaisya, or general populace) were derived from the tripartite division of ancient Indo-European society, traces of which can be detected in certain social and religious institutions of ancient Greece and Rome. To the three classes were added the Shudras, or servants, after the Indo-Aryans settled into the Punjab and began to move down into the Ganges Valley. The three original ashramas were the chaste student (brahmachari), the householder (grihastha), and the forest-dweller (vanaprastha). They were said to owe three debts: study of the Vedas (owed to the sages); a son (to the ancestors); and sacrifice (to the gods). The three goals were artha (material success), dharma (righteous social behavior), and kama (sensual pleasures). Shortly after the composition of the first Upanishads, during the rise of Buddhism (6th century BC), a fourth ashrama and a corresponding fourth goal were added: the renouncer (sannyasi), whose goal is release (moksha) from the other stages, goals, and debts.
Each of these two ways of being Hindu developed its own complementary metaphysical and social systems. The caste system and its supporting philosophy of svadharma(“one’s own dharma”) developed within the worldly way. Svadharma comprises the beliefs that each person is born to perform a specific job, marry a specific person, eat certain food, and beget children to do likewise and that it is better to fulfill one’s own dharma than that of anyone else (even if one’s own is low or reprehensible, such as that of the Harijan caste, the Untouchables, whose mere presence was once considered polluting to other castes). The primary goal of the worldly Hindu is to produce and raise a son who will make offerings to the ancestors (the shraddha ceremony). The second, renunciatory way of Hinduism, on the other hand, is based on the Upanishadic philosophy of the unity of the individual soul, or atman, with Brahman, the universal world soul, or godhead. The full realization of this is believed to be sufficient to release the worshiper from rebirth; in this view, nothing could be more detrimental to salvation than the birth of a child. Many of the goals and ideals of renunciatory Hinduism have been incorporated into worldly Hinduism, particularly the eternal dharma (sanatana dharma), an absolute and general ethical code that purports to transcend and embrace all subsidiary, relative, specific dharmas. The most important tenet of sanatana dharma for all Hindus is ahimsa, the absence of a desire to injure, which is used to justify vegetarianism (although it does not preclude physical violence toward animals or humans, or blood sacrifices in temples).
In addition to sanatana dharma, numerous attempts have been made to reconcile the two Hinduisms. The Bhagavad-Gita describes three paths to religious realization. To the path of works, or karma (here designating sacrificial and ritual acts), and the path of knowledge, or jnana (the Upanishadic meditation on the godhead), was added a mediating third path, the passionate devotion to God, or bhakti, a religious ideal that came to combine and transcend the other two paths. Bhakti in a general form can be traced in the epics and even in some of the Upanishads, but its fullest statement appears only after the Bhagavad-Gita. It gained momentum from the vernacular poems and songs to local deities, particularly those of the Alvars, Nayanars, and Virashaivas of southern India and the Bengali worshipers of Krishna (see below).
In this way Hindus have been able to reconcile their Vedantic monism (see Vedanta) with their Vedic polytheism: All the individual Hindu gods (who are said to be saguna,”with attributes”) are subsumed under the godhead (nirguna,”without attributes”), from which they all emanate. Therefore, most Hindus are devoted (through bhakti) to gods whom they worship in rituals (through karma) and whom they understand (through jnana) as aspects of ultimate reality, the material reflection of which is all an illusion (maya) wrought by God in a spirit of play (lila).