Semiotics is the study of signs. It is an interdisciplinary field that examines what signs are, how they form sign systems, and how individuals use signs to produce and communicate meaning. Semiotics is usually divided into syntactics, which addresses how signs are organized and combined; semantics, which addresses the relation between signs and their meanings; and pragmatics, which addresses the relation between signs and their users. Semiotics is related to linguistics but has a broader scope that includes nonlinguistic signs, such as maps and clothing.
Signs are things that stand for something else, such as the word cat, which stands for a carnivorous mammal. They can take many physical forms, called sign vehicles, such as sounds, images, written marks, and gestures. Icons are signs that communicate meaning through qualitative resemblance to their referents, such as a portrait of a person. Indexical signs are based on a direct physical link, such as smoke as a sign of fire. For symbolic signs, the relation between sign vehicle and referent is conventional or arbitrary, which applies to most linguistic signs. Models of signs analyze their basic components. Ferdinand de Saussure's dyadic model identifies a perceptible image and a concept as the core elements, whereas Charles Sanders Peirce's triadic model distinguishes a sign vehicle, a referent, and an effect in the interpreter's mind.
Sign systems are structured networks of interrelated signs, such as the English language. Semioticians study how signs combine to form larger units of meaning, called texts. They explore how the text's message depends on the meanings of its signs and how contextual factors and tropes influence this process. They also investigate the codes employed to communicate meaning, including conventional codes, such as the color code of traffic signals, and natural codes, such as DNA encoding hereditary information.
Semiotics has diverse applications because of the pervasive nature of signs. Many semioticians study cultural products, such as literature, art, and media, investigating both the elements used to express meaning and the subtle ideological messages they convey. The psychological activities associated with sign use are another research topic. Biosemiotics extends the scope of inquiry beyond human communication, examining sign processes within and between animals, plants, and other organisms. Because semiotics spans many disciplines, no single methodology is used across all of its subfields. Although the roots of semiotic research lie in antiquity, it was not until the late 19th and early 20th centuries that semiotics emerged as an independent field of inquiry through the work of Peirce and Saussure.
Definitions and related fields
Semiotics is the study of signs or of how meaning is created and communicated through them. Also called semiology, it examines the nature of signs, their organization into sign systems (such as language), and the ways individuals interpret and use them. Semiotics has wide-reaching applications because of the pervasive nature of signs, affecting how individuals experience phenomena, communicate ideas, and interact with their environment.
These applications make it an interdisciplinary field, originating in philosophy and linguistics and closely related to disciplines such as psychology, anthropology, sociology, and education sciences. Because most sciences rely on sign processes in some form, semiotics is sometimes characterized as a meta-discipline that provides a general approach for the analysis of signs across domains. Whether semiotics is itself a science is controversial, since there are no universally accepted theoretical assumptions or methods on which semioticians agree. Semiotics has been characterized variously as a theory, a doctrine, a movement, or a discipline. It is typically divided into three branches: semantics, syntactics, and pragmatics, which study how signs relate to their meanings, to one another, and to their users, respectively.
Semiotic inquiry overlaps with linguistics and communication theory. Like linguistics, it is concerned with the analysis of sign systems, examining the meanings of words, how they are combined to form sentences, and how they convey messages in concrete contexts. A key difference is that linguistics focuses on language, while semiotics also studies nonlinguistic signs, such as images, gestures, traffic signs, and animal calls. Communication theory examines how individuals encode, convey, and interpret both linguistic and nonlinguistic messages. It typically focuses on technical aspects of message transmission, usually between distinct organisms. Semiotics, by contrast, is concerned more broadly with meaning and meaning-making, including signs that do not involve intentional communication. For example, semioticians study naturally occurring biological signs, such as disease symptoms, and signs based on inanimate relations, such as smoke as a sign of fire.
The term semiotics derives from the Greek word (), originally associated with the study of disease symptoms. The philosopher John Locke proposed the Greek term as the name for a new field of inquiry concerned with signs in his 1690 book An Essay Concerning Human Understanding. The first use of the English term semiotics dates to the 1670s. Semiotics became a distinct field of inquiry through the work of the philosopher Charles Sanders Peirce and the linguist Ferdinand de Saussure, who are regarded as its founders.
Signs
A sign is an entity that stands for something else. For example, the word cat is a sign that stands for a carnivorous mammal. Signs direct the attention of interpreters away from themselves and toward the entities they represent. They can take many forms, such as words, images, sounds, and odors. Signs can refer to diverse types of entities, including physical objects, events, places, psychological feelings, and abstract ideas. They help people recognize patterns, make plans, predict outcomes, convey ideas, and understand the world.
Semioticians distinguish different elements of signs. The sign vehicle is the physical form that a sign takes, such as sound waves in spoken language or printed letters on a page, whereas the referent is the object it stands for. The precise number and nature of these elements are disputed, and different models of signs propose distinct analyses. The referent of a sign can itself be a sign, leading to a chain of signification. For instance, the expression red rose is a sign for a type of flower, which can itself act as a sign of love.
Semiosis is the activity or capacity of comprehending and producing signs. Also characterized as the action of signs, it involves the interplay between sign vehicle and referent as organisms interpret meaning within a given context. Different types of semiosis are distinguished by the type of organisms engaging in the sign activity, such as the contrast between anthroposemiosis involving humans, zoosemiosis involving other animals, and phytosemiosis involving plants.
Meaning, sense, and reference The meaning of a sign is what semiosis generates. Meaning is typically analyzed into two aspects: sense and reference. The terms connotation and denotation, as well as intension and extension, are also sometimes used for this distinction. The reference of a sign is the object for which it stands and the sense of a sign is the way in which that object is identified or presented. For example, when the terms morning star and evening star are used for the planet Venus, they have the same reference but different senses: morning star identifies Venus as an object visible in the morning, while evening star identifies it as an object visible in the evening. Thus, two signs can refer to the same object while differing in meaning because they present that object in different ways.
Various theories of meaning explain its nature and the conditions that determine the meanings of signs. Referential theories focus on the referential function of meaning, for instance, by characterizing meaning as the signified object or as a context-dependent function that points to objects. Ideational or mentalist theories interpret the meaning of a sign in relation to the mental states of sign users, for example, as the ideas it evokes. Pragmatic theories describe meaning based on behavioral responses and use conditions.
Types and sign relations
Semioticians distinguish various types of signs, often based on the sign relation or how the sign vehicle is connected to the referent. A historically influential classification distinguishes between conventional and natural signs. Conventional signs depend on culturally established norms and intentionality to establish the link between sign vehicle and referent. For example, the meaning of the term tree is fixed by social conventions associated with the English language rather than a natural connection between the term and trees. Natural signs, by contrast, are based on a substantial link other than conventions, as when the footprint of a bear signifies the bear's presence because the bear's body physically produced it, not because of any convention. In modern semiotics, however, the distinction between natural and conventional signs has become less central as many theorists adopted the threefold classification into icons, indices, and symbols proposed by Peirce.
Icons are signs that operate through similarity: the sign vehicle resembles or imitates its referent. This includes direct physical resemblance, as in a lifelike portrait, but also more abstract resemblance, as in metaphors and diagrams. Icons are also used in animal communication: ants of the species Pogonomyrmex badius, for example, use a smell-based warning signal whose intensity and duration resemble the intensity and duration of the danger.
Indices are signs that operate through a direct physical link. Typically, the referent is the cause of the sign vehicle. For example, smoke indicates the presence of fire because it is a physical effect produced by the fire itself. Similarly, disease symptoms are signs of the disease causing them, and a thermometer's gauge reading indicates the temperature responsible. Other material links besides a direct cause-effect relation are also possible, such as a directional signpost physically pointing the path to a nearby campsite.
Symbols are signs that operate through convention-based associations. For them, the relation between sign vehicle and referent is arbitrary. It arises from social agreements, which an individual needs to learn to decode the meaning. Examples are the numeral "2", the colors on traffic lights, and national flags.
The categories of icon, index, and symbol are not mutually exclusive, and the same sign may belong to more than one. For example, some road warning signs combine iconic elements, like an image of falling rocks to indicate a rockslide, with symbolic elements, such as a red triangle to signal danger. Various other categories are discussed in the academic literature. Thomas Sebeok expands the icon-index-symbol classification by adding three more categories: signals are signs that typically trigger behavioral responses in the receiver; symptoms are automatic, non-arbitrary signs; and names are extensional signs that identify one specific individual. Other categorizations of signs are based on the channel of transmission, vagueness, ambiguity, reliability, complexity, type of referent, and whether they are intentionally produced.
Models Models of signs seek to identify the essential components of signs. Many models have been proposed, and most introduce a unique terminology for the different components, although they often share substantial conceptual overlap. A common classification distinguishes between dyadic and triadic models.