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Communication Thomas Sebeok

All living things - whole organisms as well as their parts - are interlinked in a highly ordered fashion. Such order, or organization, is maintained by communication. Therefore, communication is that criterial attribute of life which retards the disorganizing effects of the Second Law of Thermodymics; that is, communication tends to decrease entropy locally. In the broadest way, communication can be regarded as the transmission of any influence from one part of a living system to another part, thus producing change. It is messages that are being transmitted.

The constitution of messages forms the subject matter of semiotics: their ebb and flow, how they are organized and styled, how they get from here to there and back again, how they are formulated and packaged by the orginating source, and how they are unwrapped and processed when received by the terminal destination. How does the context in which the entire transaction takes place control the makeup of messages, their generation and interpretation?

Semiotics is further concerned with two sets of interrelated historical problems: the course of development of appropriate mechanisms for processing messages by individual organisms in ontogenesis; and the evolution of such mechanisms in a species in phylogenesis. Finally, the historiography of communication studies has become a focus of attention in its own right.

The process of message exchanges, or semiosis, is an indispensable characteristic of all terrestial life forms. It is this capacity for containing, replicating, and expressing messages, of extracting their signification, that, in fact, distinguishes them more from the nonliving - except for human agents, such as computers and robots, that can be programmed to simulate communication - than any other traits often cited. The study of the twin processes of communication and signification can be regarded as ultimately a branch of the life science, or as belonging in large part to nature, in some part to culture, which is, of course, also a part of nature.

When dissolved into their elementary constituents, messages are found to perfuse the entire biosphere, the system of directed and responsive matter and energy flow which is the entirety of life on Earth.

An implication of this way of looking at communication is that the capacity for message generation and message consumption, which are commonly attributed only to humans, is here assumed to be present in the humblest forms of existence, whether bacteria, plants, animals, or fungi, and, moreover, in their component parts, such as subcellular units (for example, mitochondria), cells, organelles, organs, and so forth. The global genetic code, too, can (as it has been) quite fruitfully analyzed in communicational terms: the message orginates in a molecule, the master blueprint called DNA, its end being marked by a protein. The intricate interplay of nucleic acid and protein, the essence of life on earth, provides a prototypical model for all forms of communication.

While thus widening its angle of vision to encompass a great deal more, attention here is focused on messages emitted and received by human beings.

All human messages fall into two distinct categories: verbal messages and nonverbal messages. Language - as the array of verbal messages is collectively referred to - has, so far, been found only in the genus Homo, of which only our own subspecies, Homo sapiens sapiens, remains extant. Biologists would thus say that language is a "species-specific" trait. The study of this unique yet "species-universal" attribute of humanity, language, is the subject matter of linguistics, which is one of the most sophisticated, partially formalized branches of semiotics.

A message is a sign, or consists of a string of signs. According to a classic definition, a sign is something that stands for something else (aliquid stat pro aliquo) for some organism, and has two facets: a sensible signifier - or a perceptible impact on at least one of the sense organs of the interpretting organism - and something intelligible (the content) being signified by the former. The signified (also called the designatum) is capable of being translated, whereas the signifier (also called the sign vehicle) is not.

The human's rich repertoire of nonverbal messages - by sharp contrast with language - never constituted a unified field of study, and therefore lacks a positive integrative label. What all nonverbal messages have in common is merely that they are not linguistic. This negative delineation has led to terminological chaos in the sciences of communication, which is manifoldly compounded when the multifarious message systems employed by the millions of species of languageless creatures, as well the communicative process inside organisms, are additionally taken into account.

Nonverbal messages can, however, be distinguished from one another according to several criteria of semiotic relevance. As further discussed below, this point can be illustrated by going back to a classic discussion foud in the Hippocratic writings on medical communication, describing how the physician, relying on the patient's verbally and nonverbally reported "symptoms" combined with the "signs" observed by the physician, identifies a disease ("makes a diagnosis") and forecasts its eventual course ("make a prognosis"). In other words, a symptom belongs to a category of signs the physician elicits from the patent (for example, the verbal string "I have a stomachache," or a moan accompanying a pained facial expression as the patient points to his abdomen, or both), whereas a "sign", as this term is used in a clinical context, belongs to a category which derives from the physicians's own experience (for example, when the physicians palpates the patient's abdomen and feels a tumour). A proper diagnosis is arrived at by a summation of both reported symptoms (or "subjective" signs) and observed ("objective") signs.

The binary classification of signs (in the generic sense) into subjective symptoms and objective signs (in the specific sense) in only one of many. Cassirer, for example, had a quite different binary classification, signs and symbols, the latter being a characteristic only of humans. The most widely accepted classication today, however, is not binary but one based on a trinary principle, established by Peirce. Peirce's classication is complex and has many far-reaching ramifications, but it is rooted in a three-way distinction between icon and index, with both opposed to symbol, all of which are really different facets of one generic sign.

The context determines the predominance of this or that facet. Thus the "Stars and Stripes" is a sign in which the iconic aspect is paramount when the interpreter focuses on the number of stars (representing the fifty states now composing the Union) or the number of stripes (representing the thirteen states that origally formed the Union). If the flag is used for signaling, for example, in a race, or to reflect the country in which a boat is registered, the indexical aspect becomes ascendant. If, however, the flag is ceremonially raised or lowered, say at a funeral, we consider it to be primarily symbolic.

The standpoint of Hippocrates - whom medical historians have sometimes reverentially also labelled "the father and master of all semiotics" - hinges on an ancient but still widely prevalent distinction drawn between two types of messages: "conventional" and "natural". Conventional messages are those whose power to signify is thought to depend on some prior agreement, presumed to have been reached at some temporal juncture and thereafter accepted as a matter of custom. Such are, most importantly, messages cast in spoken or written utterances, but also frequently messages that are embodied in the shape of a parochial gesture, a tradition exercised and understood by one group of persons but not necessarily by its neighbors. The meaning of a conventional message, whether verbal or not, is invariably circumscribed by a time and a place.

So-called natural messages, on the other hand, have a power to signify the same things at all times and in all places precisely because their interpretation does not presuppose a familiarity with the conventions of a particular group. After describing certain nonverbal symptoms, Hippocrates went on to say that they "prove to have the same significance in Lybia, in Delos, and in Scythia" (Prognostic XXV). Given the quasi universality of that class of nonverbal messages physicians call symptoms, he deems it evident "that one should be right in the vast majority of instances, if one learns them well and knows how to estimate and appreciate them properly."

By contrast, what is sometimes designated as a "multimessage," or conventional gesture, is one that has a number of totally distinct meanings, the choice of interpretation depending on the time and place. Thus all Americans are familiar with the raised-hand gesture, such that the thumb and forefinger delineate a circle, which essentially signifies that something is OK. In other countries, however, the same configuration may mean something totally different: for example, "money" in Japan, "zero" or "worthless" in the South of France. In other places, the same confuration may convey an obsene comment or an insult, as it did Greece more than two thousand years ago. Again, in yet other areas, it may suggest nothing at all.

These examples illustrate just one feature by which human nonverbal messages can be distinguished in terms of their temporal and spatial distribution. Other criteria will be mentioned below.

It is convenient to being a general preliminary consideration of messages where they are assumed to originate. Their inception can be pictured as in a box, designated the source. A message can now be provisionally defined as a selection out of a code by a source. The concept of a code will be explained later, but one should immediately note that many of the rules of probability governing this act of selection are unknown.

The source box is nothing more than a formal model used for facilitating the comprehension of hypothetical constructs: given a certain input, one must, more or less, guess at what takes place to account for the output. When psychologists speak of a "black box," they assume that nothing is known about what is inside the organism or about the functioning, say, of the central nervous system. However, correlations between input and output may enable certain interferences to be made, if not about the mechanism inside the box, about how it works.

The input process is usually referred to as the formulation (or, in a particular linguistics context, the generation) of the message. A source, we say, "formulates" a message, but precisely how a human does so is not known and will remain rather enigmatic until the electrochemical machinery of the brain/mind, in its immense complexity, is far better understood. The human being, it seems reasonable to postulate, follows, by and large, generative rules to create an enormous number of novel messages appropriate to an indefinite variety of contexts, but how the human being is able to acomplish this is still an utter mystery. Detailed charting of the highly intricate and continuously readapting pathways within the three-and-a-half pound globe of tissue under the skull known as the human brain remains a task for the future.

The table shown here (Fig. 2.1) [left out in the ASCII version] summarizes possible sign sources. Engineers sometimes speak of two kinds of sources: discrete and continuous. A discrete source produces messages ("letters") selected out on an enumberable set of possibilities (called an "alphabet"); such a source might produce, for example, a communication in written English. A continuous source is one that is not discrete - say, one that produces a communication in spoken English or as a piece of music.

In the communication disciplines, as throughout the life sciences, it is both legitimate and necessary to raise questions teleonomic in aspect. Accordingly, it is proper to ask: for what purposes do sources formulate messages? The functions of messages are various. They are end-directed in the same objective sense in which all animal behaviour has a goal: an animal ingests food to gain materials and energy; its digestive apparatus and enzymes exist and operate as they do in order to promote that goal of survival. Messages embody information biologically or socially important for organisms; they are formulated, among other reasons, in order to be "transferred" to another entity, here named the destination.

The destination is the area at which the messages flow initiated by the source terminates. Its workings can, once again, be roughly segmented into two temporally sucessive processes, but in reverse: an earlier one, whose characteristics are more or less understood, and an ultimate one - usually referred to as the interpretation of the message - the manner of which shades off into unfathomed dusk; in this case, the rightmost portion, or rear end, of the diagram (Fig. 2.3) would have to be darkened.

The source is normally incapable of launching its message in the electrochemical shape in which we surmise that it was initially formulated. The reason is that each source is linked with each destination via some sort of medium, or channel, a passageway through which the two are capable of establishing and sustaining their communicative exchange. An example of a channel is the link postulated between a pair of communicating Native Americans, such that one, the source, moves a blanket over a fire, while in smoke (a form of electromagnetic energy). Any form of energy propagation can, in fact, be exploited for purposes of message transmission. Possible channels are displayed in Fig. 2.2.

It is not known how, specifcally, the messages are constructed and stacked in a hierarchy, or how their meanings are "agreed to" (that is, coded). Neurophysiologists surmise that, no matter what a message may correspond to in the external world, internally it is linked by chemical exchanges, probably functioning synchronously in various regions, which may be closely adjacent to or quite remote from one another on the two-dimensional cortical sheet of higher animals, including the human. The transformation from this unconscious parallel processing to an externalized serial string, as in speaking or writing or gesturing, must be effected by surface organ systems - in the human being, for example, the so-called organs of speech.

This crucial transduction is called encoding. Encoding happens at the interface between internal and external message systems, which, in a broad sense, stand in a specular relationship, in a homology of spatiotemporal transition probablities.

When the destination receives the encoded message - which, because of entropy (the measure of disorder in the system), can never be identical with the message formulated and launched by the source - another transduction, followed by a series of further transformations, must be effected before this message can be interpreted. The pivotal reconversion is called decoding.

"Transduction" refers to the neurobiological transmutation from one form energy to another, such as a photon undergoes when impinging on the vertebrate retina: we know that it entrains impulses in the optic nerve that change rhodopsin (a pigment in the retinal rods of the eyes), through four intermediate chemical stages, from one state to another. A message is said to be "coded" when the source and the destination are "in agreement" on a set of transformation rules used throughout the exchange.

The kind of code selected by the source depends crucially on the total sensory equipment at its disposal. Plainly, it would be abortive for an animal that is mute - as the great majority of them are - to broadcast accoustically coded messages to its fellows that may be deaf. A normal human being's sense organs are capable of registering only a small portion of ambient stimuli: thus we can generally cope only with frequently between 16 and 22,000 hertz, and are, in this respect, surpassed by the smallest bat, every dog, rodents, and countless other animals.

The range of seeing likewise differs considerably in various animals: the human being, who is incapable (without mechanical enhancement) of perceiving ultraviolet, bordering on the X-ray region to about 100 angstroms, which is readily distinguishable by the honeybee and some other insects, will scarcely encode messages in the - to the human - invisible spectrum, which could be decoded by other humans only with special intrumentation. The same is true of infared, which certain nocturnal mammals, possessing a special organ (the tapetum lucidum), causing reflected night eyeshine, can manage to communicate by "in the dark," as we cannot (save with the aid of recently developed devices). An excursion into the field of sense organs is necessary to understand the wide variety of codes utilized in nature, and by humans, to ensure that reciprocal understanding is achieved.

The very general diagram shown here (Fig.2.3) aims to synopsize the main points made thus far. This model is not to be regarded as merely a piecemeal assemblage of constituents that can be represented as the sum of properties of its several parts; on the contrary, the communicational process indispensably requires that each constituent be conceived of as functioning in relation to every other.

One very important component is omitted from the flowchart model of the communication process depicted in Fig. 2.3. This is the context in which the entire transaction is embedded. The setting in which any message is emitted, transmitted, and admitted always decisively influences its interpretation, and vice versa: the context of transactions itself continually undergoes modifications by the messages being interpreted. Messages are, in brief, context-sensitive. That much is well recognized, but just how an organism takes its environment into account remains unclear. The notion of "context" has been employed differently by various differently by various investigators, but, broadly speaking, the term refers to the organism's cognizance of conditions and manner of appropriate and effective use of messages. Context includes the whole range of the animal's cognitive systems (that is, "mind"), messages flowing parallel, as well as the memory of prior messages that have been processed or experienced and, no doubt, the anticipation of future messages expected to be brought into play.

Some students of communication have consigned the study of contexts to a nebulous area of inquiry called "pragmatics," with complementing fields designated "syntactics" and "semantics," a three-way distinction proposed by Charles Morris (1971). In his usage, "syntactics" refers to the form strings of signs. "Semantics," which presupposed the former, refers to the branch that studies the way which sings signify (or "mean"). "Pragmatics," which presupposes both of the preceding, refers to the branch that studies the origin, uses, and effects of signs.

Context is often the crucial factor in resolving the significance of a message. Thus messages encoded in the chemicals isolaveric acid and methyl mercaptan are components, respectively, of human body malodor and halitosis. This notwithstanding, the same chemicals are responsible for some of the bouquet and flavor of cheese.

The context often determines whether the destination will believe or disbelieve the communication received. For instance, imagine a little boy running up to his mother, exclaiming: "Mummy, mummy, there is a tiger in the backyard!" More likely than not, his mother will reply: "Johnny, stop making up stories!" Suppose, however, that the family lives in Venice, Florida, practically next door to the winter quarters of a famour circus which, the mother is fully aware, features a "big cats" act. Her son's exclamation is more likely to be given credence than not.

Sometimes the actual form and content of the communication are ignored at the expense of the context. A distinguished psychologist, on a whim, once carried out the following informal "experiment". Each morning, as he entered the elevator in the office building where he worked, he was accustomed to greeting his co-workers, students, and employees with a cheerful "Good morning!" in a little ceremony that was echoed by a chorus of the same stereotyped salutation. One morning he said, equally cheerfully, with a broad smile, "Go to hell!" to which everyone responded with the wonted "Good morning!" The routine context sets up certain expectations about the probable range, as the speech signal in the foregoing situation did, the destinations tend to interpret it according to their expectations rather than by the triggering effect of what the exclamations actually signifies.

The diagram pictured in Fig. 2.3 [left out in the ASCII version] might misleadingly suggest that the systems represented are static. All communication systems are, to the contrary, not just dynamic but adaptive; that is, they are self-regulated to suit both the external context (conditions of the environment) and the internal context (circumstances inherent within the system itself, such as the array of presuppositions and implicatures that characterize sentences). At successive points, intelligence mechanisms come into play to check the status of the system which can, accordingly, activate and shape coping responses; their flow is commonly described as a "feed process".

Feed processes typically move, in mutually complementary fashion, forward as well as backward, tending to form loops. Thus the source normally keeps checking whether the launched message stream reaches the destination acccording to expectations ("feedforward"), whereas the desination tends continually to confirm or to disconfirm this to the source ("feedback").

Feedforward islike a trend forecast that both biases perception and enables the source to adjust its performance in anticipation of changeful happenings. In the favourable case, it may facilitate the avoidance of mistakes. Feedback brings into the frame information about the efficacy of the system itself, information that is then "fed back" into the system, thus enabling fine-tuned adjustments on the basis of results accomplished.

Budgetary planning, in familiar organizational surroundings, is an example of feedforward: let's say that my dad (the source) tells me (the destination) by a memo (the message) how much money my academic unit may spend in the coming year, and that I then design, or reshape, my unit's activities based on this "foreknowledge." A different example: many a predator (the source) captures its prey (the destination) by a maneuver called "interception" (the message). This often means that the predator aims, not at where its quarry is, but where it is most likely to be later, at the moment of impact, that is, at a precise point ahead of the victim in its calculated trajectory.

A common example of feedback also comes from a habitual university setting. As I (the source) deliver a lecture (my message) to my class (the destination), I unintermittently monitor the students' fluctuating engrossment or tedium by way of their acoustic and optic messages broadcast back to me, wittingly or unwittingly, via a feedback loop; conscientiously, I endeavor to attune my presentation as guided by their expressions. A different example: my heartbeat (the source) is slowed or speeded up by a complex amalgam of humoral and neural factors (the message) by the vagal and sympathetic cardiac efferents (channels); changes from the normal rhythm are reported ("fed back") by sensitive interceptors (other channels) to my brain (the desination), specifying factors such as timing, volume, and pulse pressure (further messsages). The feedback loop between heart and brain provides an oscillatory input to my central nervous system on the basis of which vital readjustments are then effected. The message received (and at last interpreted) by the destination is, in practice, never identical to the message sent after having been formulated by the source. In other words, the output of the channel isn't at all tantamount to the input. This discrepancy may be due to random but persistent disturbances that variously intrude into the system and thus obscure the clarity or quality of the communication or, in extreme cases, obliterate its comprehension entirely. A channel might also, say, for secrecy, contain an interposed scrambling device. Such disarrangements, which render the output unpredictable even when the input is known, are collectively called noise.

A message always consists of amalgam of signal and noise, which can be stated as a ratio of the two. If the signal (that portion of the "intended" by the source) is greater than the noise (that portion of the message which intrudes in the course of its transmission to the destination), comprehension is, to a greater or lesser degree, ensured; if, however, the noise is greater than the signal, special techniques must be employed to restore a degree of accuracy in the reception.

To circumvent noise and thereby to decrease the probability of transmissions errors, the source habitually introjects redundancy. There are many kinds of noise and many techniques for overcoming them, but always at a price - such as slowing the source (and thereby the rate of the entire transaction). Imagine, for example, an airport traffic controller (the source) attempting to convey precise landing instructions (the message) to a pilot (the desination) by radio (the channel) during an electrical storm (noisy environmental context). One means - perhaps the simplest - whereby the controller can intromit redundancy to ensure reasonably error-free reception in such a high-risk situation is to reiterate all or parts of the original message, even at the expense of slowing him - and the process of landing - appreciably. After the delivery of every message instance, the controller might ask (feedforward): "Do you copy?" The pilot will repeat what he understands the instructions to be (feedback). If the pilot judges that a satisfactory consensus has been reached, he might so acknoweldge with the code "Roger," and conclude with "out."

A different example: When I utter a sentence in the presence of a light source, I simultaneously engage in a wide array of other bodily movements, some of them audible ("paraphonetic"), most of them visible (non-vocal as well as non-verbal). These parallel communicational strands always partially redundant to one another, a welcome fact which, under noisy conditions, reduces the degree of misunderstanding between the communicants. The force of this mundane example can be appreciated by turning off the sound on your television set or, alternatively, by leaving the sound on but masking the image.

Incidentally, geneticists have found that the relation between the (four-letter) nucleic acid code and the (twenty-letter) protein-code - the genetic code - is replete with redundancy, since several groups of three nucleotides, or triplets, along the nuclei acid chain define the same amino acids along the protein chain (that is, these groups are synonymous.

Since the question whether there is life elsewhere in the universe remains as yet wide open, communication is assumed to be confined to the terrestrial biosphere, as well as to be a universal property of life on earth.

The first traces of life, hence the phylogenesis of communication, date from the Archaean Aeon, of 3,900 to 2,500 million years ago. The earliest living world consisted of prokaryotes, such as bacteria, made up of cells in which the genes are not packaged into a membrane-enclosed nucleus. These vastly multiform micro-organisms exclusively populated Earth until about 800 million years ago.

According to a current view of biologists, different species of microbes came to form symbiotic unions among one another, which subsequently co-evolved into wholly integrated and perduring collectives of higher life forms composed of eukaryotic unicellular and multicellular organisms in which they live. Symbiotic alliances - subsuming concepts such as parasitism, mutualism, commensalism, and the like - depend crucially on communication between individual particpant of two or more species for most of the life cycles of each; such alliances eventually become permanently interwoven communities, harmoniously coordinated by means of a steady ebb and flow of electrochemical signs.

Each of the three major groups of eukaryotic organisms (in addition to a fourth, the unicellular protocists) has evolved a particular type of communication, technically and respectively called phytosemiotic, zoosemiotic, and mycosemiotic. Animals form an intermediate superphylum, mediating between the plants (which they consume) and the fungi (by which they are ultimately dissolved). Because of their pivotal position as message trasnformers, their communicative processes are the most elaborate. They are also much better studied.