There are two main theories concerning the origin of social stratification.
(i) Theory of economic determinism of Karl Marx, which is often referred to as the conflict theory and
(ii) The functionalist theory. They are stated below.
1. Conflict Theory
According to Karl Marx economic factors are responsible for the emergence of difference in social strata or social classes. Therefore social stratification defined by their relation to the means of production i.e. by their ownership or non-ownership. Thus, there are in every society two mutually conflicting classes the class of the capitalists and the class of the workers or the rich and the poor. Since these two classes have mutually opposite interests, conflicts between the two are inevitable mark maintained.
Gumplocer, Oppenheimer and others have argued that the origin of social stratification is to be found in the conquest of one group by and the conquering group normally dominates the conquered. The conquered group is forced to accept the lower state and class II. North also has expressed more or less the same opinion.
2. Functionalist Theory
Kingsley Davis; P.A. Sorokin, Mac Iver and others have rejected the conflict theory or Mark Sorokin maintained that conflict may facilitate stratification but has never originated it. He attributed social stratification mainly to inherited individual, differences in environmental conditions.
Kingslay Davis has stated that the stratification system is universal. According to him it has come into being due to the functional necessity of the social system. The main functional necessity is the requirement faced by any society of placing and motivating individuals in the social structure. Social stratification is an unconsciously evolved device by which societies ensure that the most important positions are consequently filled by the most qualified persons.
The conflict theory of Max emphasizes conflict between large and stable groups with strong community sentiments, while the Functional Theory emphasizes the integrating function of social stratification based upon individual merit and reward. Both have their own merits and demerits.