V. Pareto was a scientist-economist. He laid represented his sociological concept in the multivolume work "Treatise on General Sociology".
According to V. Pareto, sociology is a synthesis of various disciplines: law, political economy, the general history and history of religion. Being an adherent of the use of natural methodology in sociology, he called his method as "logico-empirical" method, thereby emphasizing the crucial role of observation and experiment, the results of which are presented in mathematical form.
The idea of society as a social system differed favorably from the primitive mechanistic analogies of 19th-century thinkers. He believed that at the present stage of knowledge about society, it is impossible to give a rigorous system description of all the elements entering into it in a quantitative as well as a mathematical relationship. Therefore, he considered it possible to limit himself to an analysis of the five most important factors: 1) Residue, 2) Derivatives, 3) Economic factors, 4) Heterogeneity of human beings and social groups, 5) Social mobility and circulation of elites.
The basis of social actions of people is made of unconscious psycho-biological impulses, called "Residue" (remnants), which have an innate character. People do not realize the inherent "Residue" and seek to disguise them with various moral teachings, social theories, religions, etc. So, there are "derivatives", which Pareto refers to derivatives of residue "pseudological theories and arguments", which are the essence of various ideological doctrines.
Much attention was given to the analysis of social heterogeneity (inequality and processes of social mobility and circulation of elites, associated with it). He identifies two main groups in the social structure of society: the elite stratum consisting of the most talented and literate people and the lower stratum, the managed mass, living feelings and prejudices.
Pareto identifies two main groups inside the ruling elite, that alternately come to power: they are "foxes" acting by means of cunning and deception, and "lions", distinguished by determination and strength.
The viability of political elites depends on the openness of society, which should provide an opportunity to move to the ruling elite to the most talented and energetic representatives of the lower stratum. Thanks to vertical mobility, the ruling class is constantly renewed, protecting it from degradation and at the same time preserving the implementation of the revolution.