Sign and Symbol

The Cratylus is Plato's sustained investigation of the sign. Two positions compete: Hermogenes argues that names are purely conventional (any sound can be assigned to any thing by agreement), while Cratylus argues that names are natural (each thing has a correct name belonging to it by nature). Socrates tests both views. If names were purely conventional, there would be no reason to prefer one name over another, and the art of naming would be trivial. If names were purely natural, they would need to resemble their objects, which leads to absurdity (the name "fire" is not hot). Socrates steers toward a middle position. Names are tools crafted by a "name-maker" who tries to express the nature of the thing in the sounds and syllables of the name. The success is partial and imperfect. Language reaches toward reality but never perfectly captures it. The dialogue ends with a warning: one should not study names to learn the nature of things but study things directly. Signs are useful instruments, not transparent windows.

Plato frames the question that runs through the entire tradition: is the sign-thing relation natural or conventional? Aristotle will settle on convention; Augustine will distinguish natural from conventional signs; and the debate about whether language mirrors or merely labels reality never closes.

Aristotle settles the Cratylus debate on the side of convention, with a qualification. "Spoken sounds are symbols of affections in the soul, and written marks are symbols of spoken sounds." The sounds and marks are conventional: different languages use different words for the same thing. But the mental experiences (pathemata) that words symbolize are the same for all human beings, and the things of which these experiences are likenesses are the same for all. The sign relation has three levels: things in the world, thoughts in the mind (which naturally resemble those things), and words (which conventionally express those thoughts). Aristotle also introduces the distinction between names and verbs, and between simple terms (which are neither true nor false) and propositions (which are). A name by itself ("man," "runs") signifies something but makes no truth claim. Only when names are combined in a proposition ("man runs") do truth and falsity arise. This analysis separates the theory of signs from the theory of truth and gives each its own domain.

The pressure point in Aristotle's scheme is the middle level: if mental experiences are the same for all people and naturally resemble things, then the sign relation is anchored in a kind of natural correspondence that convention merely encodes. Hobbes will detach that anchor entirely, insisting that names signify nothing beyond what speakers define them to mean — and that without fixed definitions, thought itself collapses into confusion.

Augustine provides the first comprehensive theory of the sign. A sign is a thing that, beyond the impression it makes on the senses, causes something else to come to mind. Smoke is a natural sign of fire; a word is a conventional sign of a thing or idea. Augustine's primary interest is in conventional signs, especially the words of Scripture, because the interpretation of Scripture is the practical problem that drives On Christian Doctrine. He distinguishes literal signs (which signify what they directly name) from figurative signs (which signify something beyond their literal meaning). Much of Scripture is figurative: the "rock" in "God is my rock" signifies not a stone but divine steadfastness. Correctly interpreting figurative signs requires knowledge of the original languages, of the natural world (to understand natural metaphors), and of the overall teaching of the faith (charity as the interpretive norm). Augustine also addresses the problem of ambiguous signs: when a word can bear multiple meanings, the reader must determine from context which meaning the author intended. This hermeneutic framework becomes foundational for Western biblical interpretation.

Augustine's hermeneutic leaves one question unresolved: how do we know when a sign is figurative and what it figures? His answer — charity as the interpretive norm, the faith of the Church as the final check — is theologically neat but philosophically circular. Aquinas will press for a more systematic account; the Reformation will make the dispute about figurative interpretation the fault line on which Western Christianity splits.

Aquinas inherits Aristotle's framework and deepens it. Words signify things through the mediation of concepts (intelligible species). The word "man" does not point directly to this or that particular man; it signifies the concept of human nature, and through that concept it signifies all human beings. The sign relation is triadic: word, concept, thing. The most original part of Aquinas's sign theory concerns the names of God. Can human language, derived from experience of creatures, say anything true about God? Aquinas rejects two extremes. If the word "good" meant the same thing when applied to God and to creatures (univocally), it would imply that God is a creature. If it meant something entirely different (equivocally), we could say nothing meaningful about God at all. Aquinas's answer is analogy: the word "good" applies to God and creatures in related but non-identical senses, as "healthy" applies both to an organism (which possesses health) and to medicine (which causes health). Analogical naming preserves the reality of theological language without reducing God to a creature.

Aquinas's doctrine of analogy becomes central to Catholic theology and to philosophy of language more broadly. It addresses a problem that recurs whenever language is used to describe what exceeds ordinary experience: how can finite signs point to something that outstrips their natural reach?

Hobbes strips the sign down to its mechanical function. Words are "marks" that an individual uses to recall thoughts, and "signs" that communicate thoughts to others. There is nothing natural about the connection between a word and what it signifies. Names are imposed by human decision, and their meaning is fixed by definition. "Truth consisteth in the right ordering of names in our affirmations." Truth and falsity belong to speech, not to things or to silent thoughts. Without language, there would be no truth and no falsehood, and without general names there would be no reasoning. Hobbes pushes convention to its extreme. Universal names ("man," "horse") do not correspond to universal things or universal ideas. There is nothing universal in reality; universality belongs only to names. This is a thoroughgoing nominalism. The sign has no deeper connection to reality than what convention assigns. Hobbes also warns that the abuse of words, using them without fixed definitions or with contradictory meanings, is the source of most philosophical error. Metaphysicians are particularly guilty of this.

Hobbes's account creates a paradox he does not resolve: if words mean only what convention assigns, then the definitions that ground all reasoning are themselves arbitrary — and no argument, however tightly constructed, reaches beyond the word-game its participants agreed to play. Locke will try to anchor definitions in ideas derived from experience, hoping to give language a tether to something beyond convention; Berkeley will then attack the very ideas Locke appeals to.

Locke devotes Book III of the Essay to the imperfections and abuses of language. Words are signs, but what do they signify? Not things directly (for then everyone who used a word would need acquaintance with the thing). Words signify ideas in the speaker's mind. When I say "gold," I use the sound to stand for my complex idea of a yellow, heavy, fusible metal. Communication succeeds when the hearer has a similar idea associated with the same word. It fails when speakers attach different ideas to the same sign, which happens more often than we realize. Locke distinguishes names of simple ideas (which are least liable to confusion, since the idea is determined by experience), names of mixed modes (which are most arbitrary, since the mind constructs the complex idea), and names of substances (which are intermediate, guided by experience but not fully determined by it). General words work by abstraction: the mind forms a general idea by removing particularities and associates a word with the abstracted idea. This "abstract general idea" is the meaning of the term. Locke is acutely aware that the imprecision of language is a major source of philosophical disputes and recommends careful definition as the remedy.

Locke's ideational theory of meaning dominates the British empiricist tradition. Berkeley attacks the notion of abstract general ideas; Hume refines the account. The question of whether words signify ideas rather than things continues to generate debate.

Berkeley's Introduction to the Principles attacks Locke's doctrine of abstract ideas at its root. Locke had argued that general words get their meaning from abstract general ideas, produced by stripping away the particularities from particular ideas. Berkeley finds this unintelligible. Can I form the idea of a triangle that is "neither oblique nor rectangle, neither equilateral, equicrural, nor scalenon," as Locke describes? I cannot. Every idea in the mind is particular and determinate. The word "triangle" becomes general not by standing for an abstract idea but by being used to represent any and all particular triangles. A particular idea functions as a sign for the whole class. This is a representational, not an abstractionist, account of generality. Berkeley's critique has broad implications. If there are no abstract ideas, then many philosophical puzzles dissolve, for they arise from treating words as if they named ghostly general entities. "Matter," "substance," "real essence" are abstract terms without corresponding ideas. By cleaning up the theory of signs, Berkeley aims to clean up philosophy. The lesson is that meaning depends on use, not on mental pictures stripped of content.

Berkeley's attack on abstract ideas reshapes the theory of signs. Hume takes up the point and grounds his entire philosophy on particular impressions and ideas. The question of what general words mean, if not abstract entities, remains open through the twentieth century.

Kant distinguishes two modes of rendering concepts intuitable: schematism and symbolism. A schema provides a direct sensible illustration of a concept (a drawn triangle for the concept of triangularity). A symbol provides an indirect illustration through analogy. When we call the state a "machine" or a monarchy a "body," we do not mean that the state is literally a machine; we mean that the relation of parts to the whole in a machine is analogous to the relation of citizens to the state. All our language about God, Kant argues, is symbolic in this sense: we speak of God as a "father" or as "governing" the world, not because these terms apply literally, but because the relations they describe are analogous to divine attributes. Kant thereby provides a sophisticated account of how signs can reach beyond their literal meaning without falling into mere equivocation. In the Critique of Judgment, he also discusses "aesthetic ideas," rich sensible representations in art and poetry that suggest more than any concept can capture. A beautiful image can symbolize moral ideas in ways that discursive language cannot. This is the productive power of the symbol: it makes the invisible partially visible.

Kant's theory of the symbol opens a path beyond both literal and arbitrary signification. Hegel develops the idea into a full theory of symbolic, classical, and romantic art. Freud draws on the concept of symbolism (though transformed) for the interpretation of dreams.

Freud extends the theory of signs into the unconscious. A dream is not random noise but a meaningful sign, the "royal road to the unconscious." Its manifest content (what the dreamer remembers) is a symbolic representation of its latent content (the repressed wishes and thoughts that produce it). The dream-work transforms latent into manifest through specific operations: condensation (combining multiple ideas into a single image), displacement (shifting emotional charge from one idea to another), and representability (translating abstract thoughts into visual symbols). A king in a dream may symbolize the dreamer's father; a journey may symbolize death. But Freud resists a fixed dream-dictionary. The same symbol can mean different things for different dreamers; context and association determine meaning. Freud extends this analysis to parapraxes (slips of the tongue and pen), jokes, and neurotic symptoms. In each case, a surface sign carries a hidden meaning produced by the unconscious. Psychoanalytic interpretation is the art of reading these signs, tracing them back to their source through free association and careful attention to the patient's history.

Freud transforms the theory of signs by showing that symbolic meaning operates below the threshold of consciousness. His interpretive method, whatever its scientific standing, expands the domain of the sign from logic and theology into the interior life of the individual. The idea that the mind speaks a symbolic language it does not fully understand remains influential in psychology, literary criticism, and cultural theory.