The paper is focused on the connection between general sociological theory and urban sociology. In the first part, a distinction between thick society and evanescent society is presented. In the second part, some topics of urban sociology are proposed in order to hypothesize that also in urban systems is possible to speak about thick city and evanescent city. The aim of these reflections is to stress how general and urban sociology can influence each other, and which heuristic implications can have this influence.
