Social foundations of traditional Indian society is very impressive and withstood the challenges of time, still remain unshaken. Social foundation develops in response to the social requirements of its people. Man’s philosophy of life and universe define his aspirations and direct his strivings in life. These strivings of man deeply influence his social organization. Indians believe that the soul of man is immortal and also believe on the transmigration of soul which find it’s reference in Rig Veda. Upanishad says “as his conduct and behaviour so does his self.’

Hindu Sastrakaras have regarded man as a social animal whose life and actions are said to be influenced by four factors such as desa, kala, shrama, and guna which means place or region, time, effort and natural traits respectively. Hindu social thinkers have taken these factors into consideration while formulating rules or dharma for human conduct. Indian thinkers though have recognised the importance of time and place i.e. kala  and desa in the life and conduct of man still they refrained from framing any specific rules relating to this two factors. Because it is not possible to visualise all possible variations relating to these two factors. That is why they opine in Mahabharat that according to the exigencies of time and place, what is dharma may become adharma and what is adharma may become dharma. In other words it means rules of conduct are subject to change in accordance with the changing conditions of time and place.

But Indian social thinkers have framed detailed rule in relation to other two factors i.e. shrama and guna i.e. effort and natural traits respectively. The rules relating to guna i.e. natural traits have come to be organised into varna vyavastha. This constitute one of the important cornerstone of Indian society.

The term ‘varna’ has been derived from Sanskrit root ‘Vri’ which means to choose. But literally it refers to colour, it also means choice. But the word varna was originally used to refer  to a distinction between ‘Aryans’ and the ‘non-Aryans’, but later refers to the four varnas. The Aryans used the term ‘Aryavarna’ in  the Rigveda to signify the distinction between them and the non-Aryans i.e. Dasavarna. In Rigveda along with this division i.e. Aryavarna and Dasavarna we find the three fold division of society i.e Brahmana, Kshatriya and Vaisya. But it is only in the Purusasukta hymn of Rigveda we come across the four fold division of society or Chatruvarna i.e. Brahmana, Kshatriya, Vaisya and Sudra. These four ‘Varnas’ believed to have originated from the four limbs of the supreme being the purusha i.e. from mouth, arms, thighs and feet respectively. The limbs from which these varna originated show their position and duties in society. Brahmins were at the top of the hierarchy and perform the duties of teaching and performing sacrifices. Kshatritya were next to Brahmins and were required to protect people. Vaisyas were next to Kshatriyas and were assigned the duty of agriculture and business where as the Sudras serve the above people. Thus varna vyavastha served as a system of division of labour in society.

But during Vedic age these social division were not rigid as it became in later days. During those days membership of varna was not hereditary. Lord Krishna also mention it in Bhagwat Gita i.e. “chaturvarna maya srustam guna karma vibhagashya.” Accordingly, varna vyavastha was just a division of society on the basis of natural traits and deeds. But gradually this varna vyavastha turned into caste vyavastha and became hereditary and rigid.