The Metapolis. Dictionary of Advanced Architecture. City, Technology and Society in the Information Age (Actar 2003). Per si us són d'utilitat.
Interaction is reciprocal influence of an individual on the actions of another person or persons when immediately physically present, thereby turning what was a spatial fact into a social event. Interaction is founded on the obligation of those co-present as they make themselves mutually accessible and negotiate the terms according to which a given situation is to take place. Simple physical co-presence becomes interaction at the very moment in which the minimum threshold of a social nucleus is established, the reciprocally granted and recognised possibility of giving life to, of bringing forth, a minimum social organisation. Interaction is founded on the openness of subjects to communication and to the acceptance of its rules.