During the reign of the Guptas, there was a revival of Brahmanism of a gentler and more refined form. Vaisnavism of the Vasudeva cult, centring on the prince-god Krishna and advocating renunciation by action, and Shaivism prospered, along with Buddhism and Jainism. Both the Mahayana and the Hinayana ("Lesser Vehicle"), or Theravada ("Way of the Elders"), schools flourished. The most notable feature, however, was the rise of the Buddhist Yogacara school, of which Asanga (4th century AD) and his brother Vasubandhu were the great pioneers. Toward the end of the 5th century, Dignaga, a Buddhist logician, wrote the Pramanasamuccaya ("Compendium of the Means of True Knowledge"), a work that laid the foundations of Buddhist logic.

 The greatest names of Indian philosophy belong to the post-Gupta period from the 7th to the 10th century. At that time Buddhism was on the decline and the Tantric cults were rising, a situation that led to the development of the tantric forms of Buddhism.
Shaivism was thriving in Kashmir, and Vaisnavism in the southern part of India. The great philosophers Mimamsakas Kumarila (7th century), Prabhakara (7th-8th centuries), Mandana Mishra (8th century), Shalikanatha (9th century), and Parthasarathi Mishra (10th century) belong to this age. The greatest Indian philosopher of the period, however, was Shankara. All of these men defended Brahmanism against the "unorthodox" schools, especially against the criticisms of Buddhism. The debate between Brahmanism and Buddhism was continued, on a logical level, by philosophers of the Nyaya school--Uddyotakara, Vacaspati Mishra, and Udayana (Udayanacarya).
 

Toward the end of the 12th century, creative work of the highest order began to take place in the fields of logic and epistemology in Mithila and Bengal. The 12th-13th-century philosopher Gangesa's Tattvacintamani ("The Jewel of Thought on the Nature of Things") laid the foundations of the school of Navya-Nyaya ("New-Nyaya"). Four great members of this school were Paksadhara Mishra of Mithila, Vasudeva Sarvabhauma (16th century), his disciple Raghunatha Shiromani (both of Bengal), and Gadadhara Bhattacaryya.

Religious life was marked by the rise of great mystic saints, chief of which are Ramananda, Kabir, Caitanya, and Guru Nanak, who emphasized the path of bhakti, or devotion, a wide sense of humanity, freedom of thought, and a sense of unity of all religions. Somewhat earlier than these were the great Muslim Sufi (mystic) saints, including Khwaja Mu'in-ud-Din Hasan, who emphasized asceticism and taught a philosophy that included both love of God and love of humanity.

The British period in Indian history was primarily a period of discovery of the ancient tradition (e.g., the two histories by Radhakrishnan, scholar and president of India from 1962 to 1967, and S.N. Dasgupta) and of comparison and synthesis of Indian philosophy with the philosophical ideas from the West. Among modern creative thinkers have been Mahatma Gandhi, who espoused new ideas in the fields of social, political, and educational philosophy; Sri Aurobindo, an exponent of a new school of Vedanta that he calls Integral Advaita; and K.C. Bhattacharyya, who developed a phenomenologically oriented philosophy of subjectivity that is conceived as freedom from object.
 

 The Vedic hymns  (mantras) seem to be addressed to gods and goddesses (deva, one who gives knowledge or light), who are personifications of natural forces and phenomena (Agni, the fire god; Indra, the rain god; Vayu, the wind god). But there are gods not identifiable with such phenomena (e.g., Aditi, the infinite mother of all gods; Mitra, the friend; Varuna, the guardian of truth and righteousness; Vishvakarman, the all-maker; shraddha, faith). Also, the hymns show an awareness of the unity of these deities, of the fact that it is one God who is called by different names. The famed conception of rta--meaning at once natural law, cosmic order, moral law, and the law of truth--made the transition to a monistic view of the universe as being but a manifestation of one reality about which the later hymns continue to raise fundamental questions in a poignant manner, without, however, suggesting any dogmatic answer.
 

 Of these six, the Jaina tradition identifies Nigantha with Mahavira; the designation "Ajivika" is applied, in a narrow sense, to the followers of Makkhali and in a loose sense to all nonorthodox sects other than the Jainas--the skeptics and the Lokayatas.

 Buddhism, Jainism, and the Ajivikas rejected, in common, the sacrificial polytheism of the Brahmanas and the monistic mysticism of the Upanisads. All three of them recognized the rule of natural law in the universe. Buddhism, however, retained the Vedic notions of karma and moksa, though rejecting the other fundamental concept of atman.
 
 

 Although the word duhkha in common parlance means suffering, its use by Gautama was meant to include both pleasure and pain, both happiness and suffering. There are three aspects of this conception: duhkha as suffering in the ordinary sense; duhkha arising out of the impermanence of things, even of a state of pleasure; and duhkha in the sense of five aggregates meaning that the "I" constituted by any individual is nothing but a totality of five aggregates--i.e., form, feeling, conception, disposition, and consciousness. In brief, whatever is noneternal--i.e., whatever is subject to the law of causality--is characterized by duhkha; for Gautama, this is the human situation. One who recognizes the nature of duhkha also knows its causes. Duhkha arises out of craving (trsna), craving arises out of sensation (vedana), and sensation arises out of contact (sparsha), so that man is faced with a series of conditions leading back to ignorance  (avidya)--a series in which the rise of each succeeding member depends upon the preceding one (pratityasamutpada).
 
 

 Both negative and positive accounts of Nirvana are to be found in the Buddha's teachings and in early Buddhist writings. Nirvana is a state of utter extinction, not of existence, but of passions and suffering; it is a state beyond the chain of causation, a state of freedom and spontaneity. It is in addition a state of bliss. Nirvana is not the result of a process; were it so, it would be but another perishing state. It is the truth--not, however, an eternal, everlasting substance like the atman of the Upanisads, but the truth of utter selflessness and insubstantiality of things, of the emptiness of the ego, and of the impermanence of all things. With the realization of this truth, ignorance is destroyed, and, consequently, all craving, suffering, and hatred is destroyed with it.