Indian philosophy has had a long and complicated development. A chronological history is, however, difficult to present because of the lack of concern of the ancient Indians to chronology and historical perspective. This has frustrated many serious students of the great philosophy that evolved over thousands of years. Fortunately the philosophy as was envisioned and refined by many philosophers has survived, though the names of the many philosophers have been lost. Only a broad outline of the historical aspect of the Indian philosophy and thought can be given, absent the dates and in many cases the original documents.
Broadly, the Indian philosophy can be divided into four main periods, starting around 2500 B.C.E. until about 1700 C.E. Following this, its development went into serious decline. Indian philosophy lost its dynamic spirit about the sixteenth century when India came under the influence of external powers. First the Muslim control and then the British occupation seriously undermined the Indian thought process. English educated Indians were ashamed of their heritage and tradition and tried to emulate the English in thought and life style. Only a few Vedantis like Sri Aurobindo and Vivekananda took leading roles in reviving the philosophical and religious renaissance. Only in the recent decades the West has begun to understand and accept the Indian philosophy as one of the great philosophies of the world. The future thought process of Indians would undoubtedly be in terms of a synthetic approach to Indian and Western points of view.
The first period of Indian philosophy is called the Vedic Period and may be placed between 2500 and 600 B.C.E. This is the age of the assimilation of the great Vedas, culminating in the Aranyakas and Upanishads. The Indian thought process has been profoundly influenced by the Upanishads and has remained so ever since.
The second period of Indian philosophy is called the Epic Period, dated approximately from 500 or 600 B.C.E. to 200 C.E. This was a fertile period in the philosophical development of the world in general. The great works in China, Greece and Persia coincides with this period of Indian philosophical development. Not only the great epics of Mahabharata and Ramayana were written during this period but also the early development of Buddhism, Jainism, Shaivism and Vaishnavism took place simultaneously. Bhagavad-Gita, which is a part of Mahabharata ranks as one of the three most authoritative texts of Indian philosophical literature. The philosophies of skepticism, naturalism and materialism arose and the orthodox systems of Hinduism took shape. Systematic treatises were written that brought into focus the unorthodox systems of Buddhism, Jainism and Charvaka during the Epic Period. In addition the codes of conduct, social and ethical philosophy were compiled in the Dharmashastras.
The third period is called the Sutra Period, dated approximately the early centuries of the Christian era. Most of the Sutras in short enigmatic aphorisms were written as treatises to the earlier schools of philosophical thoughts. This helped in organizing the various doctrines in a systematic, orderly form and the systems took a basic form in which they were to be preserved. In contrast to the Epic Period, when the philosophical thought and discussions had their origins, the Sutra Period saw criticism of opposing thoughts develop. The six Hindu systems, collectively called the Darshana literature developed during this period.
The fourth period of Indian philosophy is called the Scholastic Period. During this period commentaries were written on the sutras, which helped in understanding sometimes-incomprehensible terse verses. Commentaries were written on commentaries. Literature from this period, which lasts from the Sutra Period to the 17th century, is mainly explanatory. It is also controversial and often argumentative and noisy. Some of them, however, are invaluable. Shankara's commentary on the Vedanta sutra is thought of more highly than the original sutra written by Badarayana. This period also brought forth some of the greatest philosophers in addition to Shankara. They were Kumarlila, Sridhara, Ramanuja, Madhva, Vachaspati, Udayana, Bhaskara, Jayanta, Vijnabhikshu and Raghunatha. Ostensibly they are said be merely commenting on the ancient systems but in reality they have been responsible for creating their own systems. The best such examples are those of Shankara's Advaita, Ramanuja's Vihsishtadvaita and Madhva's Dvaita systems. Though they stem from the Vedanta Sutra of Badarayana, they are quite distinct in their own right. These later Indian philosophers have maintained their traditional respect for the past, but at the same time, they have been able to infuse their own free insight and direction, without seeming to break form the tradition of respect to authority.