Social change is a change in the social structures and functions of those Structures. 

Evolutionary Theory of Change

• Evolutionary theories are based on the assumption that societies gradually change from simple to more complex forms. Early sociologists beginning with auguste Comte believed that human societies evolve in a unilinear way– that is in one line of development. According to them social change meant progress toward something better. They saw change as functional and beneficial. To them the evolutionary process implied that societies would necessarily reach new and higher levels of civilization. This evolutionary view of social change was highly influenced by Charles Darwin’s theory of organic evolution. Although evolutionist’s ideas dates back to August Comte but it was Herbert spencer who presented his theory of evolution in a more systematic form.
• Spencer’s conception of the notion of social reality was influenced by biology. Adopting organismic analogy, spencer believes that like individual organism, societies were made up of inter-connected and interdependent parts. In case of society these parts are social institutions. A more or less persisting network of inter-dependent parts constitutes the social structure.
• Like organism, societies are also characterized by progressive increase in size. Increase in size is followed by increase in differentiation and integration. Thus, simple societies had relatively undifferentiated social structure. Increasing differentiation or in other words increasing division of labour is accompanied by new means of maintaining integration. Thus, societies either due to change in environment or due to internal growth of population gradually undergo evolutionary change. This change is viewed as progressive and unidirectional process involving transition from small and simple to large and complex type of societies. Spencer’s theory of change is a macro theory because the entire societies are taken as a unit of analysis.

Cyclical Theory

The structural-functional theories are generally concerned with micro and middle range theories of social change. The structural-functionalists assume that society, like the human body, is a balanced system of institutions, each of which performs a function in maintaining society. They consider ‘change’ as a constant that requires no explanation. They hold that changes disrupt the equilibrium of a society, until the change has been integrated into the culture. Societies accept and adopt those changes that are found useful (functional), while they reject changes that are useless (dysfunctional). They view that when events within and without the society disrupt the equilibrium, social institutions make adjustments to restore stability. For instance, a natural calamity, a famine, an influx of immigrants or a war may disrupt the social order and compel the social institutions to make adjustments. Robert K Merton held that “all major social structures have in due course been cumulatively modified or abruptly terminated. In either event, they have not been eternally fixed and unyielding to change”.

1. Sorokin, in his cyclical theory of social change has shown that every social system has a definite cultural stage, in which a change makes changes in the whole social system and this is social change. Sorokin, in his book “Socio Cultural Dynamics” has illustrated mainly two and overall there cultures 1. Sensate 2. Idealistic & 3. ideational culture.
2. Here sensate and ideational are extremes cultural stages. It means, reaching to any of the culture extreme level, society faces a change, that is why Sorokin believes that the whole human history is the history of cultural dynamics.
3. The distinction B/W sensate and ideational culture is the basis of social change, when society changes from one stage to another. Then all the attributes of social relation as science, religion philosophy, law, morality, art, literature etc. are changed and in that way, this is a social change widely.

Whether the change is from sensate to ideational or ideational to sensate, the motion of change is irregular, It is in the form of Fluctuation So in the sequence of change, the speed of change is sometimes high and sometimes slow and next time it may stagnate temporarily. In this way it cannot be predicted
when one cultural stage would reach to second cultural stage. This is Sorokin’s cyclical theory of change.