The first part of this article invites the reader to consider the question raised by Arendt regarding the ambiguous power that modernity gives to children, allowing reflection on a capacity-based anthropology of participation. The second part tries to specify the nature and the extent of the registers of perception and expressivity that children are able to practice when their mode of existence is filled with public presences and values. This text focuses on a paradox: the participatory movement that would like to enable children to take part in public simultaneously contributes to impoverishing their experience of public life. This paradox highlights a violent anthropological reduction imposed on children through the format of communication required by the contemporary order to take part in a liberal public life.