In this book, the author attempts to explain the nature of human society and to provide a justification of the democratic system, often charged with favoring numerousness over quality. Starting from his previously published conception of the structure and functioning of human mind, Belfiore derives a set of democratic principles that allow to conceive society as the necessary result of the trend of human actions and moral acts toward universalization, and the democratic system (based on majority rule and universal suffrage) as the only one through which actions and moral acts can reach the best possible approach to universality. Since evolution toward universality is regarded as part of mind evolution, which in turn is conceived as the objective good, democratic society is given an objective ontological and moral foundation. Likewise, the author provides new insights and offer novel solutions for many issues concerned with the complex functioning of the democratic society, such as: the nature of political parties, the political positions known as right and left, the duality of the forces that drive political activity (egoism/right/freedom versus morality/duties/equality), the voting system, the justification of majority rule, the role of leaders and elected representatives, voters' preferences, political choices, the unity-distinction of the three powers of the State, and still others. Belfiore contrasts his views with those of other thinkers, who are extensively quoted. The result is an original and exhaustive text, which will be useful for a better understanding of the democratic society.