The 5 chapters of this book investigate from different perspectives the role of the Signifier (Saussure´s Signifiant, Peirce´s Representamen) in the anthropogenetic process we are always involved as signifying animals. It is not a “summa”, but a list of materials and problems hopingly useful for a possible reconsideration of the relation between music and philosophy. A special place in this inquiry is devoted to the Greek notion of Icon, taken as the prototype manifestation of any semiotic signifier.