This volume deals with central problems in semiotics and critically discusses thinkers and trends in the field. Part I is devoted to the fundamentals of semiotics, focusing on relations between sign and interpretant, sign and reference/context and notions as common speech. Part II offers a historical-theoretical analysis of the science of signs and its problems. Part III contains two appendixes by the editor/translator, which discuss the study of the theory of signs as developed by Welby and the materiality of signs.