The Nyāya-Vaiśesika theory of the world is guided by the general spiritual view of Indian philosophy. In its attempt to explain the origin and destruction of the world it reduces all composite objects to the four kinds of atoms of earth, water, fire and air. It is called the atomic theory of the world. But it does not ignore the moral and spiritual principles.

The Buddha was born in the sixth century B.C. It was an age of spiritual restlessness and society was moving away fast from its old religious moorings.Criticism of Vedic practices had started earlier, in fact, for even the Upaniṣads belittled the efficacy of sacrificial rites and laid emphasis on knowledge of Reality as the best path of attaining a blessed hereafter.

The flourish with which the discovery of dependent origination or causal concatenation is announced in the Pali canon,shows the importance the Buddhist monks and schoolmen attached to the formula. The real point is whether the rule of law governing the destinies of sentient existence was couched in the language of the dependent origination formula by the Buddha himself or some of his followers.

Between two opposite viewpoints of eternalism (whether absolutistic or dualistic) and annihilation-ism lies the creed of the Buddha that though there is no unchanging self (ātman), still it is not a function of matter and is not completely denuded of all causal efficacy when particular bodily embodiment ceases to exist. Negation of the soul (anātma-vāda) amounts only to this, that its entitative persistence is denied.

What then is nirvana—the final goal of all spiritual endeavour? A Buddha or an Arhat attains nirvana with residue (upādhi-śeṣa) here below—becomes a Jīvan-mukta,his body continues to function till death, but his soul ceases to acquire new karma.When the body drops off, he attains nirvana without residue (anupādhi-śeṣa) as no fresh embodiment takes place.

The Jaina-Darśana, like other Indian systems, has a religious as well as a philosophical aspect.Ahimsā is the chief religious idea and anekānta- vāda—looking at reality from many points of view—constitutes the philosophical ideal.According to the Jaina tradition of the twenty-four tīrthamkaras, the first was Ṛṣabha who revealed the Ahimsā-dharma. The last of these was Mahāvīra.

Viṣṇu Purāṇa and the Bhāgavata are the two important poetical works, representing a particular type of Sanskrit religious-philosophical literature, Purāṇas. Purāṇas do not identify themselves with any particular scholastic system of philosophy or any particular sectarian religion. A leaning towards bhakti (devotion) is, however, predominant in all the Purāṇas, and this is very appealing to popular minds and hearts.

The Manu-Smṛti is the leading work on the sacred law (dharma-śāstra) of ancient India and the Artha-śāstra of Kauṭilya takes the same rank among the manuals of polity. While there is much agreement between Manu and Kauṭilya in the fundamentals of sociology, their differences indicate that views of the Smṛti belong to a slightly later age than the Artha-Śāstra.

The Bhagavad-Gītā (or the Gītā, as it is generally called) forms a part of the Mahābhārata. It ranks as one of the greatest religious documents of ancient India and holds a unique place in its religious life.A greater attempt is nowhere made to turn philosophy into practical religion and bring the individual and the universe into personal relation with a living god.