A sign is an

object Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an ...

, quality, event, or

entity An entity is something that exists as itself, as a subject or as an object, actually or potentially, concretely or abstractly, physically or not. It need not be of material existence. In particular, abstractions and legal fictions are usually ...

whose presence or occurrence indicates the probable presence or occurrence of something else. A natural sign bears a causal relation to its object—for instance, thunder is a sign of storm, or medical

symptom Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showi ...

s a sign of disease. A conventional sign signifies by agreement, as a

full stop The full stop (Commonwealth English), period (North American English), or full point , is a punctuation mark. It is used for several purposes, most often to mark the end of a declarative sentence (as distinguished from a question or exclamatio ...

signifies the end of a sentence; similarly the words and expressions of a

language Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of ...

, as well as bodily gestures, can be regarded as signs, expressing particular meanings. The physical objects most commonly referred to as signs (notices, road signs, etc., collectively known as signage) generally inform or instruct using

written text Writing is a medium of human communication which involves the representation of a language through a system of physically inscribed, mechanically transferred, or digitally represented symbols. Writing systems do not themselves constitute h ...

symbol A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...

picture An image is a visual representation of something. It can be two-dimensional, three-dimensional, or somehow otherwise feed into the visual system to convey information. An image can be an artifact, such as a photograph or other two-dimension ...

s or a combination of these. The philosophical study of signs and

s is called

semiotics Semiotics (also called semiotic studies) is the systematic study of sign processes ( semiosis) and meaning making. Semiosis is any activity, conduct, or process that involves signs, where a sign is defined as anything that communicates something ...

; this includes the study of

semiosis Semiosis (, ), or sign process, is any form of activity, conduct, or process that involves signs, including the production of meaning. A sign is anything that communicates a meaning, that is not the sign itself, to the interpreter of the sign ...

, which is the way in which signs (in the semiotic sense) operate.

Nature

Semiotics Semiotics (also called semiotic studies) is the systematic study of sign processes ( semiosis) and meaning making. Semiosis is any activity, conduct, or process that involves signs, where a sign is defined as anything that communicates something ...

epistemology Epistemology (; ), or the theory of knowledge, is the branch of philosophy concerned with knowledge. Epistemology is considered a major subfield of philosophy, along with other major subfields such as ethics, logic, and metaphysics. Epi ...

, logic, and

philosophy of language In analytic philosophy, philosophy of language investigates the nature of language and the relations between language, language users, and the world. Investigations may include inquiry into the nature of Meaning (philosophy of language), meanin ...

are concerned about the nature of signs, what they are and how they signify. The nature of signs and symbols and significations, their definition, elements, and types, is mainly established by

Aristotle Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of ...

Augustine Augustine of Hippo ( , ; la, Aurelius Augustinus Hipponensis; 13 November 354 – 28 August 430), also known as Saint Augustine, was a theologian and philosopher of Berber origin and the bishop of Hippo Regius in Numidia, Roman North Afr ...

, and

Aquinas Thomas Aquinas, OP (; it, Tommaso d'Aquino, lit=Thomas of Aquino; 1225 – 7 March 1274) was an Italian Dominican friar and priest who was an influential philosopher, theologian and jurist in the tradition of scholasticism; he is known ...

. According to these classic sources, significance is a relationship between two sorts of things: signs and the kinds of things they signify (intend, express or mean), where one term necessarily causes something else to come to the mind. Distinguishing natural signs and conventional signs, the traditional theory of signs (

) sets the following threefold partition of things: all sorts of indications, evidences, symptoms, and physical signals, there are signs which are ''always'' signs (the entities of the mind as ideas and images, thoughts and feelings, constructs and intentions); and there are signs that ''have'' to get their signification (as linguistic entities and cultural symbols). So, while natural signs serve as the source of signification, the human mind is the agency through which signs signify naturally occurring things, such as objects, states, qualities, quantities, events, processes, or relationships. Human

and

discourse Discourse is a generalization of the notion of a conversation to any form of communication. Discourse is a major topic in social theory, with work spanning fields such as sociology, anthropology, continental philosophy, and discourse analysis. ...

communication Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inqui ...

philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. ...

science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence ...

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from prem ...

mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...

poetry Poetry (derived from the Greek '' poiesis'', "making"), also called verse, is a form of literature that uses aesthetic and often rhythmic qualities of language − such as phonaesthetics, sound symbolism, and metre − to evoke meani ...

theology Theology is the systematic study of the nature of the divine and, more broadly, of religious belief. It is taught as an academic discipline, typically in universities and seminaries. It occupies itself with the unique content of analyzing th ...

, and

religion Religion is usually defined as a social- cultural system of designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relates humanity to supernatur ...

are only some of fields of human study and activity where grasping the nature of signs and symbols and patterns of signification may have a decisive value. Communication takes place without words but via the mind as a result of signs and symbols; They communicate/pass across/ messages to the human mind through their pictorial representation.

Types

The word ''sign'' has a variety of meanings in English, including: *

Sun sign In astrology, planets have a meaning different from the astronomical understanding of definition of planet, what a planet is. Before the scientific revolution, age of telescopes, the night sky was thought to consist of two very similar component ...

s in

astrology Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that claim to discern information about human affairs and terrestrial events by studying the apparent positions of celestial objects. Di ...

* Sign or signing, in communication: communicating via hand gestures, such as in

sign language Sign languages (also known as signed languages) are languages that use the visual-manual modality to convey meaning, instead of spoken words. Sign languages are expressed through manual articulation in combination with non-manual markers. Sign ...

. * Gang signal * Sign, in

Tracking (hunting) Tracking in hunting and ecology is the science and art of observing animal tracks and other signs, with the goal of gaining understanding of the landscape and the animal being tracked (the "quarry"). A further goal of tracking is the deeper un ...

: also known as Spoor (animal); trace evidence left on the ground after passage. * A

signboard Signage is the design or use of signs and symbols to communicate a message. A signage also means signs ''collectively'' or being considered as a group. The term ''signage'' is documented to have been popularized in 1975 to 1980. Signs are any ...

. * A sign, in common use, is an indication that a previously observed event is about to occur again * Sign, in

divination Divination (from Latin ''divinare'', 'to foresee, to foretell, to predict, to prophesy') is the attempt to gain insight into a question or situation by way of an occultic, standardized process or ritual. Used in various forms throughout history ...

and religion: an

omen An omen (also called ''portent'') is a phenomenon that is believed to foretell the future, often signifying the advent of change. It was commonly believed in ancient times, and still believed by some today, that omens bring divine messages fr ...

, an event or occurrence believed to foretell the future * Sign, in

ontology In metaphysics, ontology is the philosophy, philosophical study of being, as well as related concepts such as existence, Becoming (philosophy), becoming, and reality. Ontology addresses questions like how entities are grouped into Category ...

and

spirituality The meaning of ''spirituality'' has developed and expanded over time, and various meanings can be found alongside each other. Traditionally, spirituality referred to a religious process of re-formation which "aims to recover the original shape ...

: a

coincidence A coincidence is a remarkable concurrence of events or circumstances that have no apparent causal connection with one another. The perception of remarkable coincidences may lead to supernatural, occult, or paranormal claims, or it may lead t ...

or surprising event thought to reveal divine will; see synchronicity *

Sign (linguistics) In semiotics, a sign is anything that communicates a meaning that is not the sign itself to the interpreter of the sign. The meaning can be intentional, as when a word is uttered with a specific meaning, or unintentional, as when a symptom is ...

: a combination of a concept and a sound-image described by Ferdinand de Saussure * In

, the sign of a number tells whether it is positive or negative. Also, the

sign of a permutation In mathematics, when ''X'' is a finite set with at least two elements, the permutations of ''X'' (i.e. the bijective functions from ''X'' to ''X'') fall into two classes of equal size: the even permutations and the odd permutations. If any total o ...

tells whether it is the product of an even or odd number of transpositions. * Signedness, in computing, is the property that a representation of a number has one bit, the sign bit, which denotes whether the number is non-negative or negative. A number is called signed if it contains a sign bit, otherwise unsigned. See also signed number representation * Sign, in

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary ...

: an indication of some living thing's presence * Medical sign, in

medicine Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pr ...

: objective evidence of the presence of a disease or disorder, as opposed to a

, which is subjective * Sign (semiotics): the basic unit of meaning * Information sign: a notice that instructs, advises, informs or warns

people A person ( : people) is a being that has certain capacities or attributes such as reason, morality, consciousness or self-consciousness, and being a part of a culturally established form of social relations such as kinship, ownership of prope ...

Traffic sign Traffic signs or road signs are signs erected at the side of or above roads to give instructions or provide information to road users. The earliest signs were simple wooden or stone milestones. Later, signs with directional arms were introduce ...

: a sign that instructs drivers; see also

stop sign A stop sign is a traffic sign designed to notify drivers that they must come to a complete stop and make sure the intersection is safely clear of vehicles and pedestrians before continuing past the sign. In many countries, the sign is a red oc ...

speed limit Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign reflecting the maximum permitted speed - expre ...

sign, cross walk sign * Sign, in a

writing system A writing system is a method of visually representing verbal communication, based on a script and a set of rules regulating its use. While both writing and speech are useful in conveying messages, writing differs in also being a reliable fo ...

: a basic unit. Similar terms which are more specific are character, letter or

grapheme In linguistics, a grapheme is the smallest functional unit of a writing system. The word ''grapheme'' is derived and the suffix ''-eme'' by analogy with ''phoneme'' and other names of emic units. The study of graphemes is called '' graphemi ...

* Commercial signage, including

flashing sign A flashing sign is a sign that contains a sequential flashing light source where the period of time of illumination is equal to the period of non-illumination, and is used solely to attract attention in a non-informative way. The light can be inte ...

s, such as on a retail store, factory, or theatre *

Signature A signature (; from la, signare, "to sign") is a Handwriting, handwritten (and often Stylization, stylized) depiction of someone's name, nickname, or even a simple "X" or other mark that a person writes on documents as a proof of identity and ...

, in history: a handwritten depiction observed on a document to show authorship and will * For marketing or advocacy purposes, a signage refers to the collective use of signs to convey a message.

Philosophy

Stoicism

Stoic philosophy recognizes two types of signs: indicative and commemorative (also known as "suggestive" or "mnemonic" or "recollective"). Indicative signs allow people to grasp truths about entities that have not been experienced. The commemorative sign does not

"admit of being observed in conjunction with the thing signified (for the naturally non-evident object is, from the start, imperceptible and therefore cannot be observed along with any of the things apparent), but entirely of its own nature and constitution, all but uttering its voice aloud, it is said to signify that whereof it is indicative."
Sextus Empiricus Sextus Empiricus ( grc-gre, Σέξτος Ἐμπειρικός, ; ) was a Greek Pyrrhonist philosopher and Empiric school physician. His philosophical works are the most complete surviving account of ancient Greek and Roman Pyrrhonism, and ...
''Outlines of Pyrrhonism'' Book II Section 317

The commemorative sign represents something that has previously been experienced in conjunction with its object. Consequently, the object of a commemorative sign can be described empirically.

"Thus the commemorative sign, when observed in conjunction with the thing signified in a clear perception, brings us as soon as it is presented and when the thing signified has become non-evident, to a recollection of the thing observed along with it and now no longer clearly perceived - as in the case of smoke and fire; for as we have often observed these to be connected with each other, as soon as we see the one-that is to say, smoke-we recall the other-that is to say, the unseen fire."
Sextus Empiricus Sextus Empiricus ( grc-gre, Σέξτος Ἐμπειρικός, ; ) was a Greek Pyrrhonist philosopher and Empiric school physician. His philosophical works are the most complete surviving account of ancient Greek and Roman Pyrrhonism, and ...
''Outlines of Pyrrhonism'' Book II Sections 315-317

Pyrrhonsim

Pyrrhonist philosophy rejects the validity of indicative signs as they are non-empirical. It recognizes only commemorative signs.

Christianity

St. Augustine Augustine of Hippo ( , ; la, Aurelius Augustinus Hipponensis; 13 November 354 – 28 August 430), also known as Saint Augustine, was a theologian and philosopher of Berber origin and the bishop of Hippo Regius in Numidia, Roman North Afr ...

was the first man who synthesized the classical and Hellenistic theories of signs. For him a sign is a thing which is used to signify other things and to make them come to mind ('' De Doctrina Christiana'' (hereafter DDC) 1.2.2; 2.1.1). The most common signs are spoken and written words (DDC 1.2.2; 2.3.4-2.4.5). Although God cannot be fully expressible, Augustine gave emphasis to the possibility of God’s communication with humans by signs in Scripture (DDC 1.6.6). Augustine endorsed and developed the classical and Hellenistic theories of signs. Among the mainstream in the theories of signs, i.e., that of Aristotle and that of Stoics, the former theory filtered into the works of Cicero (106-43 BC, ''De inventione rhetorica'' 1.30.47-48) and Quintilian (circa 35-100, ''Institutio Oratoria'' 5.9.9-10), which regarded the sign as an instrument of inference. In his commentary on Aristotle’s ''De Interpretatione'', Ammonius said, "according to the division of the philosopher Theophrastus, the relation of speech is twofold, first in regard to the audience, to which speech signifies something, and secondly in regard to the things about which the speaker intends to persuade the audience." If we match DDC with this division, the first part belongs to DDC Book IV and the second part to DDC Books I-III. Augustine, although influenced by these theories, advanced his own theological theory of signs, with whose help one can infer the mind of God from the events and words of Scripture. Books II and III of DDC enumerate all kinds of signs and explain how to interpret them. Signs are divided into natural (''naturalia'') and conventional (''data''); the latter is divided into animal (''bestiae'') and human (''homines''); the latter is divided into non-words (''cetera'') and words (''verba''); the latter is divided into spoken words (''voces'') and written words (''litterae''); the latter is divided into unknown signs (''signa ignota'') and ambiguous signs (''signa ambigua''); both the former and the latter are divided respectively into particular signs (''signa propria'') and figurative signs (''signa translata''), among which the unknown figurative signs belong to the pagans. In addition to exegetical knowledge (Quintilian, ''Institutio Oratoria'' 1.4.1-3 and 1.8.1-21) which follows the order of reading (''lectio''), textual criticism (''emendatio''), explanation (''enarratio''), and judgment (''iudicium''), one needs to know the original language (Hebrew and Greek) and broad background information on Scripture (DDC 2.9.14-2.40.60). Augustine’s understanding of signs includes several hermeneutical presuppositions as important factors. First, the interpreter should proceed with humility, because only a humble person can grasp the truth of Scripture (DDC 2.41.62). Second, the interpreter must have a spirit of active inquiry and should not hesitate to learn and use pagan education for the purpose of leading to Christian learning, because all truth is God’s truth (DDC 2.40.60-2.42.63). Third, the heart of interpreter should be founded, rooted, and built up in love which is the final goal of the entire Scriptures (DDC 2.42.63). The sign does not function as its own goal, but its purpose lies in its role as a signification (''res significans'', DDC 3.9.13). God gave signs as a means to reveal himself; Christians need to exercise hermeneutical principles in order to understand that divine revelation. Even if the Scriptural text is obscure, it has meaningful benefits. For the obscure text prevents us from falling into pride, triggers our intelligence (DDC 2.6.7), tempers our faith in the history of revelation (DDC 3.8.12), and refines our mind to be suitable to the holy mysteries (DDC 4.8.22). When interpreting signs, the literal meaning should first be sought, and then the figurative meaning (DDC 3.10.14-3.23.33). Augustine suggests the hermeneutical principle that the obscure Scriptural verse is interpreted with the help of plain and simple verses, which formed the doctrine of "scriptura scripturae interpres" (Scripture is the Interpreter of Scripture) in the Reformation Era. Moreover, he introduces the seven rules of Tyconius the Donatist to interpret the obscure meaning of the Bible, which demonstrates his understanding that all truth belongs to God (DDC 3.3.42-3.37.56). In order to apply Augustine's hermeneutics of the sign appropriately in modern times, every division of theology must be involved and interdisciplinary approaches must be taken.

References

External links

* {{Authority control Communication Semiotics Stoicism Pyrrhonism