What do we mean by ? Why should the concepts of perception and expressivity be reinterpreted within the encompassing framework of a dynamic theory of semiotic fields and forms? Can we redeploy the concept of form in such a way as to make explicit such a native solidarity (‘chiasmatic’ would have said Merleau-Ponty) between perception, praxis and expression — and first and foremost in the activity of language, right to the heart of the life of the social and speaking animal that we are? What then would be the epistemological and ontological consequences, and how might this affect the way we describe semiolinguistic forms? This book aims to provide answers to these questions by opening up avenues of research on how to understand the linguistic and semiotic dimensions at work in the constitution of experience, both individual and collective.