Introduzione. L’abitare fluido in città e metropoli per niente fluide

The fact that young people's lifestyles are to some extent characterised by forms of residential mobility, movement and multi-activity (let's call them traits of fluidity), does not mean that the method of analysing them and the theory of interpreting them must be fluid. Neither cities, nor metropolises, nor the social structures of intergenerational and territorial inequality, nor the configurations of actors, businesses, corporations and institutions are fluid; they are, if anything, very stable, structured and structuring, based on long-term processes and governed (albeit with discontinuities) with institutional arrangements that tend to be solid (Le Galès, Vitale, 2015; Cremaschi, Le Galès, 2018; Vitale, 2024). Urbanity persists there and a more intense logic of urban action is concentrated there, according to Julie-Anne Boudreau's (2010) beautiful expression, which is anything but fluid and dispersed.