Brahmanism was facing a huge threat with the massive development of Buddhism and Jainism, i.e. the development of absolute monarchy and of a class of merchants.
Buddhism was an ideology which rejected the castes and opened the way to modernization, to a secularization of social life. Also, the question of vegetarianism was largely developed in Buddhism and Jainism, which drew a clear line between Hinduism and the others new religions.
Vegetarianism was the product of the animist tradition of the peoples oppressed by the Aryans invaders, but it was also a way to assert the capitalist way in the face of the aborigines, who lived as hunters-gatherers (aatavika) or as forest tribes (aranyacara).
Ashoka (304–232 BCE), the absolute monarch who was the first to unify virtually all of ancient India, did not only use Buddhism as his weapon, he also called for the triumph of a code of morality, or dhamma, acceptable by all religions and designed to become the new citizen culture of the empire.
The dharma-vijaya – conquest by piety – was the ideology of the new state, its principles can be found engraved all over the country, carved into rocks and stone pillars. Its most famous symbols are the four Indian lions standing back to back, and the “Ashoka Chakra”.
Ashoka called for a leap forward in civilization, by rejecting the barbarian values from the time of the Aryan domination. Vegetarianism, of course, was also a central element; it was an appeal to a peaceful way towards conscious citizenship as individuals, in place of enslavement to a barbaric system.
So, we find an appeal not to destroy life (in sanskrit prãņãtipãtaḥ, in prakrit pãņãtipãto), not to take something not given (in sanskrit adattãdãnam, in prakrit adinnãdãnaṃ), not to have unauthorized sexual intercourse (in sanskrit kãmamithyãcãraḥ, in prakrit kãmesu micchãcãro), not to lie (in sanskrit mṛṣãvãdaḥ, in prakrit musãvãdo), and not to fall into intoxicating drinks (in sanskrit surãmaireyapramãdasthãnam, in prakrit surãmerayapamãdaṭṭhãnaṃ).
Consequently, brahmanism had to undergo an inner change, and to offer a new perspective. Reincarnation had to play a central role if Brahmanism was to recover its hegemony on the masses.
The first step was military, with the destruction of the Maurya dynasty to which Ashoka belonged. The emperor Brihadratha was killed by its general Pusyamitra Sunga (185–149 BCE), who then formed an empire in the North East of ancient India, the latter thus losing its unity.
A process of general struggle against Buddhism began; the local rulers used Brahmanism as an instrument of domination and fought the negation of the caste system, while rejecting centralism.
Therefore, the ceaseless struggles between kings produced a new empire, the empire of the Gupta dynasty, which structure was not very centralized.
Under Chandra Gupta Ist, Samudra Gupta the Great, and Chandra Gupta II the Great, the Hinduist forces of ancient India began to make great use of the written word, thus producing a high level of culture geared towards a renewal of Brahmanism.
This period is therefore called the “golden age”, but it was only golden for the ruling classes, i.e. the emperor, the feudal class and the priests, who won back their central ideological positions.
The caste system began to take control of social relations, while Buddhism was gradually being squeezed out and losing its positions with the end of the centralized, unified empire, and the loss of some great urban centers.
The feudal class and the priests promoted local gods, gradually integrating them into Brahmanism to win over the masses. Even among rulers, the choice of divinity was a way to uphold one's positions: the Gupta dynasty traditionally supported the god Vishnu, whereas its rivals supported the god Shiva.
The so-called new religion incorporated a multitude of gods in order to unify the feudal classes on a general basis, so as to efficiently fight back the unifying position of Buddhism. It was the birth of what we call “Hinduism”, a term used to stress the difference with Brahmanism.
But that was not enough: another step had to be made. This step consisted in a metaphysical deepening of the religious conception of reincarnation, which would make it possible to fight Buddhism on the intellectual and ideological front.
It was of course necessary to connect this deepening with the integration of different gods from different places, which also meant a diversity of perceptions, interpretations, etc. etc.
For this reason, Hinduism built the concept of “darshan”, which means “sight” in sanskrit, and recognized six darshanas that were “official”, and therefore named “astikas” (meaning “it exists”), as opposed to “nastikas” (“it doesn't exist”) which designated Buddhism, Jainism, the materialist currents and so on, i.e. all the point of views that rejected the authority of the Vedas.
Despite the differences, all the new Hinduist currents considered that moksha (“liberation”) was the goal, which means an end to the process of reincarnation of the self.
But whereas Buddhism negated the individual and considered liberation as an extinction of the self – the famous Nirvana –, Hinduism as a whole explained that the end of reincarnation meant the coalescence with God's supersoul.
Brahmanism offered a way up to the top of society, Hinduism extended the process to God itself.
The six darshanas were the following:
* Mimansa (“investigation”), also called Pūrva Mimamsa (“former enquiry”) is a school created by Jaimini in the the 3rd century BC, directly in reaction to Buddhism and consisting in a new reading of the Vedas, in particular by Bhartṛhari.
Liberation goes through the religious understanding of the revelation; it is a rather traditional path, an attempt to relaunch Brahmanism through apparent “self-criticism”.
* Samkhya (“empirical”), a schcool mainly based on the book Samkhya Karika (circa 200 CE), is a deism competing directly with Buddhism, considering that there is one God on one side (“Puruṣa”, consciousness) and a world on the other side (“prakriti”, phenomenal realm of matter).
Each soul is a part of the Puruṣa imprisoned in matter because of desire, and therefore the goal is liberation from matter.
* The Yoga (coming either from yujir yoga - yoke or yuj samādhau - to concentrate) is really famous in France; in practice it is a religious “path” to liberation, with methods of meditation to attain the “divine”.
Its major work consists in the 196 Indian sūtras (aphorisms) which form the Yoga Sūtras of the Patañjali, who lived between the second and the fourth century CE.
* Nyaya (“recursion”) is a path mostly based on Sutras that were written by Aksapada Gautama in the 2nd century CE.
It is a school based on logic, where the conscience is “raised” into the cognition of the “divine”.
* Vaisheshika is a path which tried to develop an atomist interpretation of the world, and merged with the Nyaya school.
* Vedanta (“the end of the vedas”) also called Uttarā Mīmāṃsā (“higher enquiry”) is a “path” that produced some major works giving its identity to Hinduism, which we shall see in details.