Auguste Comte saw the science of society as essentially similar to natural science. His positivist approach was based on the principle of direct observation, which could be explained by theoretical statements based on establishing causal, law-like generalizations. The task of sociology, according to Comte, was to gain reliable knowledge of the social world in order to make predictions about it, and, on the basis of those predictions, to intervene and shape social life in progressive ways. Comte's positivist philosophy was clearly inspired by what he saw as the fabulous predictive power of the natural sciences. Comte's ideas were extremely influential and his theory of the development of the sciences was an inspiration to other thinkers working with theories of evolutionary social development. Comte saw each science as passing through three stages: the theological (or religious), the metaphysical (or philosophical) and finally the positive (or scientific), with each stage representing a form of human mental development. He argued that the history of the sciences demonstrated this pattern of movement, with social life being the last area to move into the positive stage and sociology the final discipline.
Auguste Comte divided sociology into two major parts – static and dynamic sociology. The idea of this division is borrowed from biology that is in keeping with his notions of a hierarchy of sciences. Biology is a science that precedes sociology and thus shares common features with this science. The static sociology studies the conditions of the existence of society while the dynamic sociology studies the continuous movement or laws of the succession of individual stages in society.
Auguste Comte's ideas have influenced several major sociologists like Sorokin, J.S Mill, Max Weber, Emile Durkheim and several others. His laws of three stages have been more or less rejected by the contemporary sociologists. But the essential notion of stages of development in ideas and culture in a modified form has been accepted.
English philosopher and sociologist Herbert Spencer (1820- 1903) drew on Comte's ideas and argued that, just as the world of nature was subject to biological evolution, so societies were subject to social evolution. This took the form of structural differentiation through which simple societies develop over time into more and more complex forms with an increasingly diverse array of separate social institutions; and functional adaptation the way that societies accommodate themselves to their environment. Spencer argued that it was through structural differentiation that societies became functionally better adapted, and the industrial societies of the nineteenth century were essentially demonstrating a form of social evolution, emerging out of the more static and hierarchical societies that preceded them. Spencer also thought that the principle of 'survival of the fittest' applied in social as well as biological evolution, and he was not in favor of state intervention to support the vulnerable or disadvantaged.
Spencer tried to apply in his investigation of all fields of knowledge his idea of social evolution. In comparing human society with an organism that is essentially what organic analogy means. He noted the differences between the biological organism and society. He maintained that a society as an entity is something more than and other than an organism even though human organisms are members of it. It is a total system of elements of social organization and their interdependent functions. It is a super –organic entity an organizational entity over and above the level of the organism. Spencer accepted the ideas that a society was more than a collective nature for a number of individuals. That is it is not a collection of several individuals but is a distinct entity. The whole is more than its parts. Thus a house is more than a mere collection of bricks, wood and stone. It involves a certain ordering of parts. He believed that unlike biological organisms where the parts exist for the benefit of the whole, in society it is the whole that exists for the benefit of the parts. Spencer told people through sociology that human beings should not interfere with the natural processes in societies.
He had great faith in the innate instinct of freedom and believed any interference with this instinct to be harmful. His concept of society as a super –organic system had several problems. He was unable to see culture as part of an integrated whole. His explanation regarding the social evolution of societies from simple to compound and so on was also full of errors. However he formulated an integral theory of all reality. His law of evolution is a cosmic law and his theory is a philosophical theory rather than sociological. His ideas became popular because they served the need of his time the desire for unifying knowledge and the need to explain in a scientific manner the liassez faire principle.
Functionalism holds that society is a complex system whose various parts work together to produce stability and solidarity. According to this approach, the discipline of sociology should investigate the relationship of parts of society to each other and to society as a whole. We can analyze the religious beliefs and customs of a society, for example, by showing how they relate to other institutions within it, for the different parts of a society develop in close relation to one another.
To study the function of a social practice or institution is to analyze the contribution which that practice, or institution, makes to the continuation of society. Functionalists including Comte and Durkheim have often used an organic analogy to compare the operation of society to that of a living organism. They argue that the parts of society work together, just as the various parts of the human body do, for the benefit of society as a whole. To study a bodily organ like the heart, we need to show how it relates to other parts of the body. By pumping blood around the body, the heart plays a vital role in the continuation of the life of the organism. Similarly, analyzing the function of a social item means showing the part it plays in the continued existence and health of a society. Functionalism emphasizes the importance of moral consensus, in maintaining order and stability in society. Moral consensus exists when most people in a society share the same values. Functionalists regard order and balance as the normal state of society this social equilibrium is grounded in the existence of a moral consensus among the members of society. For instance, Durkheim argued that religion reaffirms people's adherence to core social values, thereby contributing to the maintenance of social cohesion.
Talcott Parsons and Robert K. Merton drew extensively on Durkheim, were two of its most prominent adherents. Merton's version of functionalism has been particularly influential. Merton distinguished between manifest and latent functions. Manifest functions are those known to, and intended by, the participants in a specific type of social activity. Latent functions are consequences of that activity of which participants are unaware. Merton also distinguished between functions and dysfunctions. To look for the dysfunctional aspects of social behavior means focusing on features of social life that challenges the existing order of things.