There are several fundamental models for representing the structure of a sign—dyadic, triadic, and tetradic.
2.3.1. The Dyadic Model
The dyadic model of the sign structure is attributed to Ferdinand de Saussure, who viewed the sign as a two-sided entity.
Although his considerations are directed toward the linguistic sign, they hold value for general sign theory.
“The linguistic sign unites not a thing and a name, but a concept and an acoustic image. The linguistic sign is therefore a two-sided psychological entity, which can be represented as follows:
- Acoustic Image
- Concept
These two elements are closely linked and mutually presuppose each other.
For Saussure, they are inseparable, like the two sides of a sheet of paper.
He emphasizes that it would be incorrect to consider only the tangible, material form of the sign as the sign:
We call the combination of concept and acoustic image a sign, but in practice, this term usually denotes only the acoustic image, for instance, the word ‘tree’ and so on. We forget that if ‘tree’ is called a sign, it is only insofar as it carries the concept of a tree, so the thought of the tangible side includes the thought of the whole.
Saussure suggests calling the two sides of the sign the signifier (Signifiant) and the signified (Signifié). They relate to each other like form and content—for example, the linguistic form “tree” corresponds to the content “tree.”
For example, the word “coffee” as a linguistic sign would look like this:
- Signified: “Coffee”
- Signifier: “Coffee” – written (graphic) form corresponding to written speech; “Coffee” – pronounced (acoustic) form corresponding to spoken speech.
The same model can be applied to non-linguistic signs.
Since Saussure was not interested in the extra-linguistic reality, the dyadic model does not include the object that the linguistic sign denotes.
2.3.2. The Triadic Model
It is more common to include the object in the structure of the sign. The idea of the three-sided nature of the sign is believed to have originated with the German logician and mathematician Gottlob Frege (1848-1925).
In 1892, he wrote:
It is natural to associate with the sign (Zeichen) not only what it denotes and what may be called its denotation (Bedeutung) but also what I will call the sense (Sinn) of the sign.
Peirce, though reflecting on the “triadic relation” that connects the sign with “the denoted object and the mind” as early as 1885, only formulated his concept of the sign as a triad consisting of the representamen (the form representing the sign), the interpretant (a mental image or thought arising in the interpreter’s mind), and the object (the object from reality that the sign replaces) in 1899.
In truth, if we wish to be historically accurate, the idea of the triadic relation of the sign belongs neither to Peirce nor Frege but to the Stoics, of whom Sextus Empiricus wrote:
The Stoics say that three things are linked: that which is signified; that which signifies; and the event.
Of these, that which signifies (semaion) is the speech—for example, ‘Dion’;
that which is signified (semainomenon) is the thing itself, revealed through it and which we perceive as existing through our thought, but which barbarians do not understand, even though they are able to hear the spoken word;
while the event (tyche) is what exists externally—for example, Dion himself.
Two of these things are material: the speech and the event, while one is immaterial—that is the signified thing, which may be true or false.
The triadic model is used in the well-known “semantic triangle” by the English scholars Charles Ogden and Ivor Richards:
- Thought or Reference (concept)
- Symbol (signifier)
- Referent (object)
The latest version of the triadic model belongs to the famous German semiotician Winfried Nöth, who—without introducing anything new—strictly distinguishes between the concepts of “sign” and “signifier” following the example of Morris.
Nöth points out that the term “sign” often conceals what is the signifier and that the term “sign” should refer to the entire sign structure.
2.3.3. The Tetradic Model
If the triadic model is expanded by adding the interpreter as a fourth factor, as proposed by Morris, a tetradic model emerges:
- O – Object
- Z – Sign
- S – Sign producer
- T – Interpreter
However, this model lacks the category of “meaning” of the sign.
Another type of tetradic model is proposed by Rousen Rousenov, who argues for correcting the triadic model of the sign situation altogether and presenting it as a fourfold system.
- Sign (O)
- Meaning (B)
- Object (C)
- Concept (U)
In this model, one can sense the influence of the distinction between Sinn (sense) and Bedeutung (denotation), established in logic after Frege, which some authors translate with the term “meaning.”
Among the three models, the triadic one is the most popular and widespread, having earned the right to be considered classical in semiotics.
