Sign relation

A sign relation is the basic construct in the theory of signs, also known as semiotics, as developed by Charles Sanders Peirce.

Thus, if a sunflower, in turning towards the sun, becomes by that very act fully capable, without further condition, of reproducing a sunflower which turns in precisely corresponding ways toward the sun, and of doing so with the same reproductive power, the sunflower would become a Representamen of the sun. (C.S. Peirce, "Syllabus" (c. 1902), Collected Papers, CP 2.274).

In his picturesque illustration of a sign relation, along with his tracing of a corresponding sign process, or semiosis, Peirce uses the technical term representamen for his concept of a sign, but the shorter word is precise enough, so long as one recognizes that its meaning in a particular theory of signs is given by a specific definition of what it means to be a sign.

One of Peirce's clearest and most complete definitions of a sign is one that he gives, not incidentally, in the context of defining "logic", and so it is informative to view it in that setting.

Logic will here be defined as formal semiotic. A definition of a sign will be given which no more refers to human thought than does the definition of a line as the place which a particle occupies, part by part, during a lapse of time. Namely, a sign is something, A, which brings something, B, its interpretant sign determined or created by it, into the same sort of correspondence with something, C, its object, as that in which itself stands to C. It is from this definition, together with a definition of "formal", that I deduce mathematically the principles of logic. I also make a historical review of all the definitions and conceptions of logic, and show, not merely that my definition is no novelty, but that my non-psychological conception of logic has virtually been quite generally held, though not generally recognized. (C.S. Peirce, NEM 4, 20–21).

In the general discussion of diverse theories of signs, the question frequently arises whether signhood is an absolute, essential, indelible, or ontological property of a thing, or whether it is a relational, interpretive, and mutable role that a thing can be said to have only within a particular context of relationships.

Peirce's definition of a sign defines it in relation to its object and its interpretant sign, and thus it defines signhood in relative terms, by means of a predicate with three places. In this definition, signhood is a role in a triadic relation, a role that a thing bears or plays in a given context of relationships — it is not as an absolute, non-relative property of a thing-in-itself, one that it possesses independently of all relationships to other things.

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