Semiotics has defined itself from its very beginnings as the discipline of signs. Yet, as Anna Maria Lorusso observes, the notion of the sign has never been either simple or univocal. Dictionaries offer very different definitions: a sign may be “a clue,” “a gesture,” “an act or a word,” or a “graphic expression” capable of representing an entity. This variety immediately reveals how broad the concept is: gestures, words, images, or behaviors may all function as signs, even though they belong to very different domains.
The word “Italy” is a sign, but so too can be the drawing of Italy on a map, the national flag, or the blue jersey worn by the national football team during a match. Precisely this heterogeneity led semiotic reflection to reformulate the problem: instead of considering the sign as a given entity, the discipline gradually shifted its attention toward processes of signification. As Lorusso explains, this means examining “the procedures that produce signs” and the relations that connect a certain expression with a certain content.
Within this perspective the sign does not disappear; rather, it is rethought in dynamic terms. Lorusso emphasizes that “the sign becomes a two-sided sign function,” whose relation is not established once and for all but is defined culturally and socially. This implies that the relation between expression and content varies according to historical periods, contexts, and interpretive practices.
One of the most influential theoretical elaborations of this relational conception of the sign is that proposed by Charles Sanders Peirce. In the Peircean perspective, the sign is fundamentally a reference: something that stands for something else from a certain point of view. A sign never illuminates its object completely; it selects only some relevant aspects of it.
Peirce describes this dynamic through a triadic relation: a sign stands for something, under a certain respect, for a thought that interprets it. The structure of the sign therefore involves three elements: the object, the sign itself—what Peirce calls the representamen—and the interpretant, that is, the sign that translates and interprets the first.
An example clarifies this mechanism. If on the one hand we have a striped animal and on the other the word “zebra,” the relation between the word and the animal is not immediately evident to someone who does not know the language. An interpretant is needed to establish the correlation between that sequence of letters and the animal to which it refers. Only when someone understands that “zebra” stands for that animal does the word function as a sign.
The interpretant may take many forms. It may be a dictionary definition, a drawing, a gesture, or even a behavior. Peirce provides a particularly clear example: if a general orders his soldiers “About face!” and the soldiers immediately change direction, the soldiers’ behavior constitutes the interpretant of the order. This is not a mechanical reaction but the result of understanding a sign and interpreting it.
Since every interpretant is itself a sign, it may generate further interpretations. Semiosis therefore has no definitive endpoint: every sign can be explained by other signs, which in turn require further interpretations. For this reason Peirce conceives thought itself as unlimited semiosis, a continuous production of signs and interpretations that develops on the basis of prior knowledge. Some interpretations, when they become widely shared and recurrent, stabilize into interpretive habits, conventions, or codes, yet they always remain open to further transformation.
Alongside this triadic conception of the sign, a different theoretical perspective developed within linguistics, beginning with the work of Ferdinand de Saussure. In the Course in General Linguistics, the linguistic sign is defined as an entity composed of two sides: signifier and signified. The relation that links these two components is arbitrary: there is no natural reason why a given sound should correspond to a particular content.
Arbitrary does not mean subjective. Language is a social fact: the associations between words and meanings are shared within a linguistic community. What matters is not a natural relation between word and thing but the position each sign occupies within the system of language. As Saussure observes, language is a system of differences: each sign acquires value only in relation to the other signs from which it differs.
Louis Hjelmslev develops these premises further by proposing a more general formulation of the sign. Instead of speaking of signifier and signified, he distinguishes two planes of language: the plane of expression and the plane of content. These two planes are inseparable and are further articulated into forms and substances. Forms organize the amorphous matter of experience, structuring the continuum of meaning.
As Anna Maria Lorusso recalls, language therefore does not simply reflect the world; it contributes to structuring it. Every language articulates the matter of experience according to its own criteria, creating different divisions. An example concerns the field of kinship relations. The Italian word nipote may refer both to the child of a sibling and to the child of one’s own child, regardless of gender; the English word nephew, by contrast, refers specifically to the male child of a brother or sister. The difference does not lie in the reality of kinship relations but in the way languages organize and classify the continuum of experience.
From these structuralist premises contemporary semiotics developed in the 1960s. Roland Barthes, in Elements of Semiology, explicitly resumes Saussure’s lesson and highlights two aspects that would become particularly influential: the contractual nature of the sign and the coexistence of conventional and motivated elements within systems of signification.
Within this tradition stands the theoretical project of Algirdas Julien Greimas. In Structural Semantics, Greimas aims to analyze the plane of content by identifying its minimal units, the semes, in a manner analogous to what phonology had done with phonemes. The meaning of a sign can thus be described as the combination of elementary semantic traits.
The sememe results from the combination of a relatively stable nuclear set of semes and contextual semes that may vary according to discursive situations. From this combination multiple effects of meaning emerge. The lexeme, by contrast, represents the potential set of interpretations that may develop from a shared nucleus of meaning. Greimas illustrates this mechanism through the analysis of the lexeme “head,” showing how a single term can open a multiplicity of semantic paths.
A further development of this perspective is proposed by François Rastier, who emphasizes the decisive role of context in activating semantic traits. The distinction between defining traits and accessory traits, Rastier argues, is plausible only at an abstract level: in concrete situations contextual traits may become central and contribute decisively to the construction of meaning.
Through these developments semiotics gradually shifted its attention from the study of isolated signs to the study of processes of signification and textualization. Lorusso notes that, as the discipline took shape, it increasingly privileged the analysis of sign production practices and the forms of discourse.
In this direction also lies Umberto Eco’s reflection in A Theory of Semiotics. Eco analyzes the modes of sign production and shows that the identity of a sign depends not only on the codes that organize it but also on the material practices through which it is produced and used. A sign no longer appears as the mere manifestation of an underlying code but as the result of a complex interaction among the material qualities of expression, the competencies of subjects, and communicative purposes.
The sign thus emerges as the point where interpretive, systemic, and productive relations converge. Rather than a stable object, it appears as the outcome of cultural and social processes that continuously organize and transform meaning.
Bibliographical reference: Anna Maria Lorusso (ed.), Semiotica, Raffaello Cortina Editore, 2005.