The University of Chicago :: Theories of Media :: Keywords Glossary
:: symbol-index-icon
Johansen, Jorgen Dines (1988). "The Distinction between Icon, Index,
and Symbol in the Study of Literature," Semiotic Theory and Practice,
Notes
symbol, index, icon
Created by American polymath Charles Sanders Peirce (1839-1914), the
symbol/index/icon triad remains a tool of analysis at the core of
semiotics, a discipline which studies signs and their meanings. As
communication (including the non-deliberate and the non-human),
symbol/index/icon analysis is now used throughout many disciplines.
Peirce (pronounced purse) originally developed the symbol/index/icon
triad as one component in a massively complex formal system of
(Johansen 2002, 5). Of Peirce's many ways of distinguishing signs, the
symbol/index/icon triad focuses on the relations of signs to their
objects: symbols have a convention-based relationships with their
influenced by their objects (e.g. a weathervane or a thermometer); and
icons have specific properties in common with their objects (e.g.
portraits, diagrams) (Johansen 2002, 51). Even at this basic level,
photograph: it has properties in common with its object, and is
therefore an icon; it is directly and physically influenced by its
object, and is therefore an index; and lastly it requires a learned
As each term is considered in greater detail, keep in mind that as a
completly abstract system, the symbol/index/icon triad applies equally
to any and all media or form of communication, prefering none over
computer keyboard is a symbol, as are those things not specifically
alphabetic or numeric: $, %, &, #, @, etc. Unlike indices or icons,
the symbols are not signs without an interpreter or "reader."
Originally called "likenesses" by Peirce, icons have a "topological
similarity" to their object (Sebok 28). Classical paintings and
similarity" to their object (Sebok 28). Classical paintings and
photographs are obviously icons, as they visually resemble their
objects. This resemblance need not be tangible: "every algebraical
objects. This resemblance need not be tangible: "every algebraical
equation is an icon, in so far as it exhibits, by means of the
algebraical signs (which are not themselves icons), the relations of
equation is an icon, in so far as it exhibits, by means of the
algebraical signs (which are not themselves icons), the relations of
the quantities concerned" (Peirce 107). Along these lines, Peirce
the quantities concerned" (Peirce 107). Along these lines, Peirce
creates three subcategories of icon: image, metaphor and diagram.
Images share "simple qualities" or "sensory qualities" with their
broader: the thermometer previously described as index can also be
described as metaphoric icon: there is a parallelism in the
translation of heat into an increased volume of the mercury column.
While symbols required interpretants and indices required their
objects, icons have no such requirements. Peirce uses the example of a
Euclidian diagram: streaks of pencil lead can represent a geometric
Under a Peircian analysis, the visual aid itself is not dyadic, but
triadic. The tree is an icon, "arbor" is a symbol, and everything else
(the oval, the arrows, the midline) are indices which direct the
Peirce's overall semiotic approach. Beyond the examples already
provided, Peirce interpreted the symbol/index/icon triad through many
other analytic triads. These interpretations and comparisons are not
as they appear frequently in Peircian literature. A few examples, with
terms ordered to express congruencies to symbol/index/icon: the
legisign/sinsign/qualisign triad organizes signs by relation to their
concepts abstracted away from all media. Not coincidentally, Peirce
viewed the symbol/index/icon triad as "the most fundamental division
of signs," and the majority of semioticians continue to agree
The University of Chicago :: Theories of Media :: Keywords Glossary
:: symbol-index-icon