The subject of this book is the thought of the American pragmatist and founder of semiotics, Charles Sanders Peirce. The book collects the papers presented to the International Conference Semiotics and Philosophy in C.S. Peirce (Milan, April 2005), together with some additional new contributions by well-known Peirce scholars, bearing witness to the vigour of Peircean scholarship in Italy and also hosting some of the most significant international voices on this topic. The book is introduced by the two editors and is divided into three sections, corresponding to the three main areas of the most interesting contemporary reflection on Peirce. Namely, Semiotics and the Logic of Inquiry (part I); Abduction and Philosophy of Mathematics (part II); Peirce and the Western Tradition. (part III). The analysis is carried out from a semiotic perspective, in which semiotics should not be understood as a specific doctrine but rather as the philosophical core of Peirce's system. As we read in the introduction: it is semiotics and philosophy or, rather, semiotics as philosophy and philosophy as semiotics, which emerge from a reading of these papers.