One universal law that Comte saw at work in all sciences he called the 'law of three phases'. It is by his statement of this law that he is best known in the English-speaking world; namely, that society has gone through three phases: Theological, Metaphysical, and Scientific. He also gave the name "Positive" to the last of these because of the polysemic connotations of the word.

The Theological phase was seen from the perspective of 19th century France as preceding the Enlightenment, in which man's place in society and society's restrictions upon man were referenced to God. By the "Metaphysical" phase, he was not referring to the Metaphysics of Aristotle or any other ancient Greek philosopher, for Comte was rooted in the problems of French society subsequent to the revolution of 1789. This Metaphysical phase involved the justification of universal rights as being on a vauntedly higher plane than the authority of any human ruler to countermand, although said rights were not referenced to the sacred beyond mere metaphor. What he announced by his term of the Scientific phase, which came into being after the failure of the revolution and of Napoleon, was that people could find solutions to social problems and bring them into force despite the proclamations of human rights or prophecy of the will of God. In this regard he was similar to Karl Marx and Jeremy Bentham. For its time, this idea of a Scientific phase was considered up-to-date, although from a later standpoint it is too derivative of classical physics and academic history.

The other universal law he called the 'encyclopedic law'. By combining these laws, Comte developed a systematic and hierarchical classification of all sciences, including inorganic physics (astronomy, earth science and chemistry) and organic physics (biology and for the first time, physique sociale, later renamed sociologie).

This idea of a special science—not the humanities, not metaphysics—for the social was prominent in the 19th century and not unique to Comte. The ambitious—many would say grandiose—way that Comte conceived of it, however, was unique.

Comte saw this new science, sociology, as the last and greatest of all sciences, one that would include all other sciences, and which would integrate and relate their findings into a cohesive whole.

He coined the word "altruism" to refer to what he believed to be a moral obligations of individuals to serve others and place their interests above one's own. He opposed the idea of individual rights, maintaining that they were not consistent with this supposed ethical obligation (Catechisme Positiviste).

As already mentioned, Comte formulated the law of three stages, one of the first theories of the social evolutionism: that human development (social progress) progresses from the theological stage, in which nature was mythically conceived and man sought the explanation of natural phenomena from supernatural beings, through metaphysical stage in which nature was conceived of as a result of obscure forces and man sought the explanation of natural phenomena from them until the final positive stage in which all abstract and obscure forces are discarded, and natural phenomena are explained by their constant relationship. This progress is forced through the development of human mind, and increasing application of thought, reasoning and logic to the understanding of world.

During his lifetime, Comte's work was sometimes viewed skeptically because he elevated Postivism to a religion and named himself the Pope of Positivism. Comte coined the term "sociology", and is usually regarded as the first sociologist. His emphasis on the interconnectedness of different social elements was a forerunner of modern functionalism. Nevertheless, like many others from his time, certain elements of his work are regarded as eccentric and unscientific, and his grand vision of sociology as the center-piece of all the sciences never came to fruition.

His emphasis on a quantitative, mathematical basis for decision-making remains with us today. It is a foundation of the modern notion of Positivism, modern quantitative statistical analysis, and business decision-making. His description of the continuing cyclical relationship between theory and practice is seen in modern business systems of Total Quality Management and Continuous Quality Improvement where advocates describe a continuous cycle of theory and practice through the four-part cycle of plan, do, check, and act. Despite his advocacy of quantitative analysis, Comte saw a limit in its ability to help explain social phenomena. On page 59 of the 1855 translation cited above, Comte wrote, "Social phenomena, being more complicated still, are even more out of the question, as subjects for mathematical analysis. It is not that a mathematical basis does not exist in these cases, ... but that our faculties are too limited for the working of problems so intricate."

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The kingdom of the heavens and the earth belongs to Allah. He indeed is able to do all things. -Quran, Al-Imran, Surah 3:189

Somayya