Part 1: Sociophysics: setting the frame.- What is sociophysics about?.- The question: do humans behave like atoms?.- Sociophysics: the origins.- Sociophysics: weaknesses, achievements and challenges.- Part II: Discovering the wonderful (and maybe scary) world of Sociophysics.- Sociophysics: an overview of emblematic founding models.- Universal features of group decision making.- The dictatorship paradox of democratic bottom-up voting.- The dynamics of spontaneous coalition-fragmentation versus global coalitions.- Terrorism and the percolation of passive supporters.- The modeling of opinion dynamics.- By way of caution.- Part III: Democratic voting in bottom-up hierarchical structures: from advantages and setbacks to dictatorship paradoxes.- Highlights of the Part.- Basic mechanisms for the perfect democratic structure.- Going to applications.- Touching on a fundamental aspect of nature, both physical and human.- Dictatorship paradoxes of Democratic voting in hierarchical structures.- Part IV: The risky business of alliances in bottom-up democratic voting with three-choice competition.- Bottom-up democratic voting in a three-choice competition.- So sorry, that's the end of the tour!.- I thank you.