J. and R. show that G. Guillaume was a precursor of the linguistics of 'énonciation', long before Bally, Benveniste, etc.; his theory of the psychomechanics of language, unlike Saussurean linguistics and 'structuralism', gives pride of place to the role of the utterer (and of the addressee) in the study of language, and includes a treatment of such modern issues as presupposition or the speech act.