This book provides a gradient model of intersubjectivity and social cognition in language. Through an interdisciplinary synthesis, the author proposes three levels of linguistic acts: those aimed at the speaker’s benefit alone, those expressing concern for an interlocutor, and those indicating concern for societal reactions. There is a continuum of egocentric to extended intersubjectivity, which includes co-actionality, immediate intersubjectivity, and collective constructions. The model is applied to study children’s mastery of intersubjective polysemy and verbal organization, and to determine “social mind” capabilities in autism spectrum disorders. While non-linguistic topics and further empirical validation are outside the scope, this innovative interdisciplinary approach meaningfully extends understanding of the intertwined nature of language, cognition, and social engagement.