Intersubject

Intersubject, short for intersubjectivity, is a term used in philosophy, psychology, and social science to denote the shared or common understanding that arises during social interaction. It describes how people converge on meanings, expectations, and norms that enable communication and coordinated action. The concept emphasizes that knowledge arises not solely from private mental states but through interpersonal engagement.

Historical background: In philosophy, phenomenology treated intersubjectivity as the ground for objectivity, arguing that the lifeworld is validated through others. Husserl and later Schutz and Luckmann explored how everyday reality is maintained by shared conventions. In sociology and anthropology, social constructionist approaches view knowledge as collectively produced and reproduced.

Key concepts: joint attention and shared intentionality; alignment of actions, perceptions, and linguistic meanings; negotiation of meaning through dialogue and gesture; the dynamic, context-dependent nature of understanding.

Domains and applications: developmental psychology studies how infants acquire joint attention and theory of mind. Linguistics and conversation analysis examine how speakers achieve mutual understanding via turn-taking and repairs. Philosophy discusses epistemic justification and objectivity. In cognitive science and human–computer interaction, intersubjectivity informs models of social intelligence and collaborative interfaces.

Critique: The term is used variably; some distinguish intersubjectivity from intersubjective objectivity or social constructionism. Critics warn of overgeneralizing shared meaning and ignoring power relations and cultural variation.