Combining theory from cognitive semantics and pragmatics, this book offers both a new model and a new usage-based method for the understanding of intersubjectivity, and how social cognition is expressed linguistically at different levels of complexity. Bringing together ideas from linguistics and theory of mind, Tantucci demonstrates the way in which speakers constantly monitor and project their interlocutor's reactions to what is being said, and sets out three distinct categories of social cognition in first language acquisition and language change. He also shows how this model can be applied in different settings and includes a range of examples from languages across the globe, to demonstrate the cross-linguistic universality of the model. Additionally the book offers insights into the gradient dimension of intersubjectivity in language evolution and across the autistic spectrum. Original and innovative, it will be invaluable for researchers in cognitive linguistics, pragmatics, historical linguistics, applied linguistics and cognitive psychology.