It presents the concepts (mediums, first / second order observation, self-poiesis, complexity, contingency, paradox, de-paradoxisation, structure, semantics, structural coupling, irritation, rejection), the functions of each theorized social system, and central axes of the work of Luhmann (functional differentiation, the subject evacuation, reduced complexity, increased improbability, critical semantics old Europe, and promotion of contingency as the heart of all normativity). It shows the movements that are made over time in the use of concepts (distinction medium / organization has been replaced by the distinction medium / form, complexity ceases to be seen as the property of an objective reality to become the attribute of a perspective on the world and the environment, etc.). It shows what the normative implications unstated perspective of Luhmann; it traces some of the main criticisms it has drawn; it outlines several reconciliations with other theorists (Donna Haraway, Michel Foucault, Richard Rorty, Carl Schmitt, Chantal Mouffe, Ernesto Laclau, Antonio Negri, Judith Butler, Michael Hardt). It shows the extent of the spread and impact of the work of Luhmann (concerning in particular the approach of ecological disaster), and indicates certain avenues to continue to explore (including installation and deployment of global society contemporary, on which the idea of globalization, by Jean-Sébastien Guy, recently offered an important lights).
A book on which one can rely to penetrate the rich mysteries of the most imposing sociological work and the most singular of the twentieth century.
