The author of this blog is Swapnil Nayan, A 2nd-year student BA LLB (Hons) student from the National University of Study and Research in Law, Ranchi.
Untouchability was a result of the Hindu Varna System or the cast system which was prevalent through the Indian society. The society was divided into four classes of people viz. Brahmin, Kshatriyas, Vaisya, and Sudra. In the division Brahmins occupied the most superior position and the Sudras were considered the most inferior. The division was said to be ordained from the deity. The four varnas originated from different parts of God’s body. The Brahmin from his mouth, The Kshatriya from his arms, The Vaisya from his thighs and The Sudras from his feet.This belief of this origination gave a mythological sanction over the division and those being the member of the society was bound to follow it. This ladder-like division caused Sudras to be discriminated and ill-treated by the upper class. With the advent of time the three castes occupied better positions in the society and the Sudras were reduced to mere servants to the other classes. The division was like watertight compartments and hence intermarriage and inter dining became a taboo. The downtrodden position of the Sudras bestowed them with many restrictions some of them being milking Cows, since Cows were considered a holy animal and since its milk was used in religious rites, they were prohibited from milking them. Other restrictions were wearing Yagnopavita (Janeva), reading the Vedas and kindling sacred fire.
Later, the position of Sudras deteriorated under Manu when they were prohibited to participate in any governing activities. Sudras were believed to be worse than animals and Brahmins were not allowed to eat food prepared by them as it was believed that if they did so, in the next life would be born as a pig. Even the law discriminated against the Sudras, for similar offenses, Sudras were heavily punished whereas Brahmins escaped with little or no punishment. 
THEORY OF ORIGIN OF UNTOUCHABLITY (BRIEF)
The Evolutionary theory postulates the emergence of a fifth caste called Panchamas which was the result of the division of Sudras. With the advent of time even Sudras acquired professional skills and thus acquired lands and property. Those who remained poor and devoid of skills were the Panchamas. Slowly Sudras developed a feeling of contempt for the Panchamas. They were treated as mere animals. A mere touch of a person of the Panchamas caste rendered the people of another caste inclusive of Sudras polluted and a laborious ritual and ceremony had to be observed to obtain ablution. The people belonging to Panchamas were treated as casteless also called ‘avarnas”. Continuous Oppression reduced them to servitude. They were expected to serve beyond all questions. They were ostracized and excluded from the society. Even touching them was considered as a sin. They were also named as Harijans, Chandals, and Pariahs.
The Caste System was so deep-rooted in Indian society that any mixing of the members of different caste especially in matrimonial relationships were considered sinful. The children begotten from mixed caste marriages were untouchables. A child begotten by a male of Shudra caste and female of Brahmin caste was branded as Chandala.. Further a son of a brahmin by a Shudra woman is called Nishada..
SOCIAL DIMENSIONS OF UNTOUCHABILITY
During the seventh century, the works of Manu Smriti were widely followed as law. It narrated the deplorable state of untouchables. Their dwellings were outside villages. They were made to wear the skin of dead animals and ornaments of black iron. They ate from broken dishes and utensils. People pursuing religious duty were strictly ordered to prevent any conversation or physical touch. Untouchables were ordered to lift the corpses of the deceased who didn’t have any relatives. Their movement in towns were highly regulated. They were prohibited to wander in the city at nights and during the day their movement must be restricted to following the king’s commands. The Chandals would be detected by their unique dialect and sweeping was said to be their hereditary occupation.
During 700AD the perverse effect of untouchability reached its epitome. Even Gautam Buddha came forward and revolted against this social evil and caste superiority.
The social dimensions of untouchability were also discussed in the works of foreign travelers who observed the Indian society and were baffled by the presence of an outcast group. In the works of Fahien, who visited India in the 5th Century A.D during the reign of Chandragupta II Vikramaditya of the Gupta dynasty. The traveler was astonished by the fact that t place where people didn’t kill any living creature or drank any intoxicating liquor or even consume onion and garlic treats a particular caste with such barbarism. The outcasts before entering the village would notify everyone of this cast by throwing a piece of wood so that people would be cautious and prevent any potential physical contacts or conversation. Such was the impact of untouchability in the Indian Society.
Another Chinese Traveller Heun Tsang who traveled India between 628 A.D. and 645 A.D. during the reign of Harshavardhana, the last great Hindu ruler. He too reiterated the status of the outcasts conforming to the works of Fahien. According to him, the Chandals or untouchables used to live outside the cities, announced their arrival to make people cautious and also ate onion and garlic. This makes the reader cognizant of the fact that the Chandals consumed the discarded food and this was one of the reasons for their considered impurity.
Decline in Buddhism and the rise of Brahmanism was another reason for the rise of untouchability in India. The decline commenced under Pusyamitra Sunga and was almost complete in the period of Shankaracharya, who lived between 788 A.D. – 820 A.D.
In the words of J.H. Hutton,“The origin of the position of exterior castes is partly racial, partly religious and partly a matter of social custom”
The social practice of despising the untouchables in some areas are under continuum. Untouchables were not allowed to use the public wells for drinking water and ghats for bathing etc. They were severely punished on the mere instance of their shadow being cast on a member of the higher strata of the society. A strict prohibition fell upon participating or rendering even a slight help in any religious activities. They were not allowed to read any religious text. Vedas recitation was to be stopped even if a Shudra woman was sighted at a distance.The religious texts gave a sanction on the practices of the higher caste people of the society.
The Social outcast of the untouchables compelled them to live in deplorable conditions dwelling in dirt slums, eating the discarded, wearing the rejected, and enduring the ever-continuing social hatred. The higher caste people averted their existence. According to the religious text one who engages in a sin of conversing with this downtrodden faction of the society would be reborn as a pig.One of the reasons postulated by Scholars such a B.R. Ambedkar of the origin of untouchability was their consumption of beef as Hindus considered cow to be a sacred animal. This practice of the downtrodden disgusted the upper caste and developed a feeling of hatred against the untouchables. This hatred was one of the reasons for their suffering revulsion.
A Jain text Brihatkalpa Bhashya, states that medas, who were regarded as untouchables in ancient India engaged in hunting for food. From the Vyavahara Bhasya, we come to know that Syapakas who were also untouchables cooked the flesh of dogs and sold bowstrings. The status of the untouchables reduced them to render discarded and petty jobs with not allowed to use public resources had to consume rejected food which caused them to be considered as impure and subject to social disgust. In a nutshell, the social practices caused a loop for them to remain in their pitiable condition.
Another untouchables called Chamaras, were despised because they indulged in the work of a filthy and impure commodity which was leather.
Not only were the outclassed people made to do discarded jobs but according to the religious texts, factions of untouchables were compelled to do particular jobs. According to Vishnu Smriti, the chandals should live executing the criminals sentenced to death. The Panas were associated with the cremation of corpses. The religious texts branded the status of untouchables to some of the downtrodden communities. Atri declares a washerman, a leather-worker, a cane-worker, a fisherman and a Bhil to be outcastes.
A person of upper-caste was believed to have been polluted by the mere touch of the member of the casteless group. The person who was polluted by such touch should cleanse himself by bathing.
 Manu Smriti Chapter- 1 Verse 31.
 Vasistha Dharma Sastra, Chapter- 4
 Kathaka Samhita, (XXXI- 2)
 Vasistha Dharma Sastra, Chapter-6, Verses 27-29
 Manu Smriti
 E.S. Yurlova, Scheduled Caste in India, (New Delhi, 1990), p.1.
 Dharma Sutra
 Baudhayana Dharma Sutra, G.Buhler (tr.), Sacred Books of the East, Vol.XIV, Oxford, I.9.17.7.
 G.S. Ghurye, op.cit,pp.312-313.
 R Sangeeta Rao: Caste System In India, (New Delhi, 1989) pp. 72-80
 J.H. Hutton,op.cit, p.207.
 Vishnusmriti Chapter- XVIII, Verses- 11-15
 Manu Smriti
 Manu Smriti Chapter- 10, Verse 36
 G.S. Ghurye, op. cit., p. 98
 Dilip Hiro: The Untouchables of India, (Bangalore, 1983) p.12.