According to Comte, each branch of our knowledge passes successively through the different theoretical conditions. It is known as law of three stages. The main aim of this principle is that it provides the basis of sociological thinking.
The three stages are:
1. Theological or fictitious stage:
According to Comte in this stage, "all theoretical conceptions, whether general or special bear a supernatural impress". Unable to discover the natural causes of the various happenings, the primitive men attributed them to imaginary or divine forces. This stage is also divided into three sub-stages as (a) Fetishism (b) Polytheism (c) Monotheism.
(a) Fetishism -During this sub-stage, man accepts the existence of the spirit or the soul. It did not admit priesthood.
(b) Polytheism - During this sub-stage, man begins to believe in magic and allied activities. He then transplants or imposes special god in every object. Thus they believed in several gods and created the class of priests to get the goodwill and the blessings of these gods.
(c) Monotheism - During this sub-stage of the theological stage man believes that there is only one centre of power which guides and controls all the activities of the world. Thus man believed in the superhuman power of only one god.
2. Metaphysical or abstract stage:
This stage being an improvement upon the earlier stage, it was believed that the abstract power or force guides and determines the events in the world. Metaphysical thinking discards belief in concrete god.
3. Scientific or positive stage:
The observation and classification of facts are the beginning of the scientific stage, where there is no place for any belief or superstition. Everything concludes rationally.
Positivism means the philosophical system of Auguste Comte, recognising only positive facts in observable phenomena, and rejecting metaphysics and theism and religious system founded on this. Thus, Comte was against all types of irrational elements in social thinking. Comte argued, "As long as man believes that social events are always exposed to disturbances by the accidental intervention of the legislators no human or divine no scientific provisions of them would be possible".
Comte not only developed the concept of three stages in the development of human intellect but also observed three stages in the development of society or social organization.