Hitherto in India it has not been the individual who has undergone the process; he inherits the social position of the caste in which he is born, and, as a rule, retains it through life without the power of altering it.

It is the caste, as a whole, or at least one of its important sections or subcastes, which gradually rises or falls in social position, and the process may extend over generations or even centuries.
In the _Brief Sketch of the Caste System of the North-Western Provinces and Oudh_, Mr.J.C.Nesfield puts forward the view that the whole basis of the caste system is the division of occupations, and that the social gradation of castes corresponds precisely to the different periods of civilisation during which their traditional occupations originated.

Thus the lowest castes are those allied to the primitive occupation of hunting, Pasi, Bhar, Bahelia, because the pursuit of wild animals was the earliest stage in the development of human industry.

Next above these come the fishing castes, fishing being considered somewhat superior to hunting, because water is a more sacred element among Hindus than land, and there is less apparent cruelty in the capturing of fish than the slaughtering of animals; these are the Kahars, Kewats, Dhimars and others.

Above these come the pastoral castes--Ghosi, Gadaria, Gujar and Ahir; and above them the agricultural castes, following the order in which these occupations were adopted during the progress of civilisation.