Sign and symbol

Something that stands for something else - and the question of how much of that standing-for is convention.

Theme: Logic, language and interpretation
Tradition: Cross-tradition
Term: σημεῖον · sēmeion
Term fixed: 1868

In plain terms

A footprint stands for a person. A portrait stands for a sitter. The word dog stands for dogs. All three are signs, and they work in three quite different ways.

The footprint was caused by what it indicates - there is a physical connection, and you cannot fake it without faking the cause. The portrait resembles what it depicts, so someone who has never seen the convention can still make something of it. The word resembles nothing and was caused by nothing; it works purely because a community treats it as standing for that.

That third kind is the most powerful and the most fragile. It carries anything, and it carries nothing at all to anyone outside the convention - which becomes a practical problem the moment you need to communicate with people who will not share yours.

As a philosopher would put it

Peirce's trichotomy is the standard analytic frame. An icon signifies by resemblance, an index by causal or existential connection, a symbol by convention or habit. Most real signs mix the three: a photograph is both icon and index, a road sign both icon and symbol.

Saussure's structuralist account is independent and different in shape. The linguistic sign joins signifier and signified, the relation is arbitrary, and value comes from difference within a system rather than from any positive content - which is what makes his framework structural rather than referential.

Augustine's earlier division into natural signs, which signify without intent, and given signs, which are used to communicate, prefigures the index-symbol split. Derrida's critique takes Saussure's own principle further, arguing that if meaning depends on difference then it is never fully present in any sign and is always deferred - which is where the tradition splits into semiotics as a science and deconstruction as its solvent.

Where you meet it

The Waste Isolation Pilot Plant in New Mexico stores transuranic waste that will be dangerous for about ten thousand years. In 1991 and 1993 the Department of Energy convened panels to design markers that would still communicate danger at the end of that period.

The panels concluded that no symbol could be relied on. The radiation trefoil is under a century old and is already read as a logo as often as a warning; the skull and crossbones has meant piracy, poison and a sports team within recorded memory. Writing was ruled out on the grounds that no language has survived that long unchanged.

What they proposed instead leaned on icon and index rather than symbol: earthworks of jagged blocks, a landscape designed to feel hostile and useless, materials with no salvage value, and information redundantly encoded at several scales. It is an engineering project premised on the conclusion that convention is the weakest way to mean something, and it is still the clearest practical demonstration of Peirce's distinction anyone has produced.

What is actually disputed

How much signification is conventional.

Saussure's arbitrariness thesis makes the sign-signified link unmotivated, which fits words well and fits gestures, images and warning marks badly. Peirce's framework allows non-conventional signification, which handles those cases and makes the boundaries fuzzy, since resemblance is itself partly conventional - perspective drawing has to be learned.

The practical question is whether anything means without a shared code. The strong conventionalist answer is no, and the strong iconic answer is that some resemblances are recognisable across any culture. The evidence is mixed: some facial expressions and some spatial metaphors travel widely, and a great deal that designers assume is universal does not. The waste-marker panels split on exactly this, and their solution - redundancy across icon, index and symbol at multiple scales - is what you do when the question has not been settled and the deadline is ten thousand years.

Commonly confused with

symbol in the loose sense Ordinary usage calls anything emblematic a symbol. In Peirce's sense a symbol is specifically a sign working by convention, which includes every ordinary word.

Defined against

Proposition A sign is the vehicle; a proposition is what a sentence made of signs says, and conflating them is a standard confusion

Philosophers

Charles Sanders Peirce The icon-index-symbol division
Augustine of Hippo Natural and given signs, the ancient framework
Jacques Derrida The argument that meaning is never fully present in a sign
Paul-Michel Foucault Sign systems as historical formations
Ludwig Wittgenstein Signs as getting their life from use rather than from correspondence

Works

How to Make Our Ideas Clear The pragmatist setting of Peirce's semiotics
Confessions Signs and language learning, in the famous passage Wittgenstein attacks
Of Grammatology Writing, difference and deferred meaning
The Order of Things Sign systems across historical periods
Philosophical Investigations The attack on the picture of language as naming

Schools

Classical Pragmatism Where the trichotomy is developed
Structuralism Where the sign becomes a system of differences
Post-Structuralism Where that system is shown to be unstable
Patristics Where the ancient theory of signs is worked out
Ordinary Language Philosophy Where signs are subordinated to use

Related concepts

Meaning 1892 · Reference 1905 · Language game 1953 · Concept 1781 · Interpretation 1819

Augustine's account of signs is the influential ancient treatment; Peirce's three-way division into icon, index and symbol, and Saussure's signifier-signified pair, are the two independent modern foundations of the subject.