The glimpse of the cultures of the world reveals that no society is ‘classless’, that is uncertified. All the known established societies of the world are stratified in one way or the other. According to Wilbert Moore and Kingsley Davis, the stratification system evolved in all the societies due to the functional necessity. As they have pointed out, the main functional necessity of the system is: ‘… the requirement faced by any society of placing and motivating individuals in the social structure… Social inequality is, thus, an unconsciously evolved device by which societies ensure that the most important positions are conscientiously filled by the most qualified persons.’ As analysed by eminent sociologist H. M. Johnson, certain things here can be noted about the ‘functional necessity’ of the class stratification system.

1. Encourages hard work:
One of the main functions of class stratification is to induce people to work hard to live up to the values. Those who best fulfil the values of a particular society are normally rewarded with greater prestige and social acceptance by others. It is known that occupations are ranked high if their functions are highly important and the required personnel is very scarce. Hard work, prolonged training and heavy burden of responsibility are associated with such occupational positions. People undertaking such works are rewarded with money, prestige, comforts, and so on. Still we cannot say that all those positions which are regarded as important are adequately compensated for.

2. Ensures circulation of elites:
To some extent, class stratification helps to ensure what is often called ‘the circulation of the elite’. When a high degree of prestige comforts and other rewards are offered for certain positions, there will be some competition for them. This process of competition helps to ensure that the more efficient people are able to rise to the top, where their ability can best be used.

3. Serves an economic function:
The competitive aspect has a kind of economic function in that it helps to ensure the rational use of available talent. It is also functionally necessary to offer differential rewards if the positions at the top are largely ascribed as it is in the case of the caste system. Even in the caste system, the people at the top can lose their prestige if they fail
to maintain certain standards. Hence, differential rewards provide the incentives for the upper classes to work at maintaining their positions.

4. Prevents waste of resources:
The stratification system prevents the waste ofscarce resources. The men in the elite class actually possess scarce and socially valued abilities and qualities, whether these are inherited or acquired. Because of their possession of these qualities, their enjoyment of some privileges, such as extra comfort and immunity from doing menial work, are functionally justified. It becomes functionally beneficial for the society to make use of their talents without being wasted. For example, it would be a waste to pour the resources of society into the training of doctors and engineers, and then make them work as peons and attendants. When once certain individuals are chosen and are trained for certain difficult positions, it would be dysfunctional to waste their time and energy on tasks for which there is enough manpower.

5. Stabilizes and reinforces the attitudes and skills:
Members of a class normally try to limit their relations to their own class. More intimate relationships are mostly found between fellow class-members. Even this tendency has its own function. It tends to stabilize and reinforce the attitudes and skills that may be the basis of upper-class position. Those who have similar values and interests tend to associate comfortably with one another. Their frequent association itself confirms their common values and interests.

6. Helps to pursue different professions or jobs:
The values, attitudes and qualities of different classes do differ. This difference is also functional for society to some extent because society needs manual as well as non- manual workers. Many jobs are not attractive to highly trained or ‘refined’ people for they are socialized to aspire for certain other jobs. Because of the early influence of family and socialization, the individuals imbibe in them certain values, attitudes and qualities relevant to the social class to which they belong. This will influence their selection of jobs.

7. Social control:
Further to the extent that ‘lower class’ cultural characteristics are essential to society, the classes are, of course, functional. In fact, certain amount of mutual antagonism between social classes is also functional. To some extent, upper-class and lower-class groups can act as negative reference groups for each other. Thus, they act as a means of social control also.

8. Controlling effect on the ‘shady’ world:
Class stratification has another social control function. Even in the ‘shady’ world of gamblers and in the underworld of lower criminals, black-marketers, racketeers,
smugglers and so on, the legitimate class structure has got respectability. They know that money is not substitute for prestige but only a compensation for renouncing it. Hence, instead of continuing in a profitable shady career, such people want to gain respectability for their money and for their children, and they try to enter legitimate fields and become philanthropists and patrons of the arts. Thus, the legitimate class structure continues to attract the shady classes and the underworld. This attraction exerts a social control function.