The Communication Turn in the Theory of Social Systems


Systems Research and Behavioural Science (forthcoming)


Loet Leydesdorff

Science &  Technology Dynamics

Department of Communication Studies, Oude Hoogstraat 24

1012 CE  Amsterdam, The Netherlands;





The theory of social systems has been contested as a part of sociology. Social order can be expected to emerge as an expectation that is communicated. A communication can be provided with meaning and meaning may evolve into codified meaning. The social system can thus be considered as developing in layers of communication among reflexive actors. At the interfaces between systems theory, communication theory, and evolution theory puzzles emerge which can also be formulated as analytical and empirical questions. The mathematical theory of communication can be used for the clarification of the relations among these different perspectives, since a message is expected to contain an information.





Perhaps more than any other science, sociology can be considered as a science in crisis (Gouldner, 1970). Shortly after the Second World War, Talcott Parsons and Alfred Schutz—two of the leading sociologists of that time—exchanged letters in which they ‘agreed to disagree’ (Grathoff, 1978). The relative incommensurability between the interactionist perspective on social action and macro-sociological analysis of social systems and institutions was thereafter increasingly accepted. Giddens, for example, stated that each of these two traditions of thought seems to have respected the domain of the other: ‘The result has been a sort of mutual accommodation, organized around a division of labour between micro- and macro-sociological analysis’ (Giddens, 1981, p. 168).


The reduction of these research programs to one perspective or another can only be a provisional solution for the theoretical dilemma. The crisis cannot be disguised by calling the discipline poly-paradigmatic, or solved by denying the very function of theorizing; for example, by claiming priority for an ‘empirical’ orientation towards ‘social problems’ using ‘middle-range’ theories. In my opinion, new advances in the relevant theories enable us to specify a sociological theory of communications that provides us with heuristics for and theoretical guidance in sociological research. Three theories have to be specifically recombined:


1.       systems theory is necessary in order to understand the complexity of the architecture, but the system’s operation has to be specified so that it includes reflexive interactions. In other words, social systems should not be reified;


2.       a reformulation of communication theory is required based on the analytical rigour of the mathematical theory of communication, but further extended to appreciate the reflexive character of inter-human communication; and


3.       a reformulation of evolution theory is needed in order to explain the dynamics of the system(s) under study. Biological evolution theory cannot provide a sufficient basis for explaining cultural evolution since this biological theory is part of the cultural evolution.


The German sociologist Niklas Luhmann specified this program of theory construction already in 1975:

            No matter how abstractly formulated are a general theory of systems, a general theory of evolution and a general theory of communication, all three theoretical components are necessary for the specifically sociological theory of society. They are mutually interdependent. (...)

                The decisive questions now become: How are these various theories related to one another? What unifies them? How must a theory that integrates them be constructed?[1]


At that time, Luhmann was formulating his theory program in opposition to Habermas’ proposal for a theory of communicative action (cf. Habermas and Luhmann, 1971). He particularly wanted to combine a systems-theoretical perspective with a communication-theoretical one. In his later work (e.g., 1984 and 1997) Luhmann defined communication as the evolutionary operator of the social system.


However, Luhmann failed to operationalize communication in terms of available (e.g., mathematical) theories of communication. Therefore, his systems theoretical notions have remained insufficient for guiding empirical research and eventually hypothesis testing. In the study of scientific communications, for example, citations can be used as an instrument for the indexing, recall, and retrieval because one can expect that these relations among documents are highly codified. The modelling enables us to test empirical hypotheses, for example, the emergence of the modern citation in the late 19th century (Leydesdorff and Wouters, 1999).


Habermas (1987) argued against Luhmann that individuation and socialization are only possible on the basis of linguistic structures. In my opinion, this critique touches the blind spot of sociological systems theory as a meta-biology (Maturana, 1978; cf. Leydesdorff, 2000). However, Habermas did not elaborate this perspective to a sociological theory of communication. The communicative competencies of the actors are not explained as a sociological variable, but based on the human embeddedness in language as a social condition. Language is then not further analyzed as an evolution of communication, but considered as a metabiologically given (cf. Pinker, 1994).



Communication of information and meaning


Whereas the paradigm shift from action theory towards communication theory was fully reflected in Luhmann’s sociology, the difference between the self-organization of social systems and the autopoiesis of biological systems remained underspecified. As different from biological systems, social communication systems allow for communication about observations from within the system and/or from another perspective. Observers are able to participate both in the variation and in the relevant selections; Giddens (1976) introduced in this context the metaphor of a ‘double hermeneutics.’


Through language the distinction between uncertainty and meaningful information can be communicated, and the implied codification can be changed reflexively without becoming confused. The social system evolves by this complex dynamics of communication among reflexive actors (Luhmann, 1986). A complex dynamics, however, can be decomposed into subdynamics. As noted, among the relevant subdynamics are (1) the evolutionary development of the system, (2) the communicative operation of the social system, and (3) the reflexive reconstruction of the complex system. The three theories (evolution theory, communication theory, and social systems theory) that reflect on these subdynamics, have internal relations, but their semantics are very different (Leydesdorff, 2001).


For example, the relation between ‘selection’ (evolution theory) and ‘meaning’ (communication theory) can be specified: an uncertainty can be provided with meaning by making a distinction between ‘signal’ and ‘noise’. The selection of ‘signals’ from the ‘noise’, however, can be made at each moment in time. Providing a system with meaning assumes the capacity to make a comparison among possible selections and thus to perform an operation over time.



Information, uncertainty, and meaning


Shannon’s (1948) definition of information as uncertainty has remained counterintuitive (e.g., Brillouin, 1962; Bailey, 1994). Shannon detached himself from the sociological implications by stating that “[t]hese semantic aspects of communication are irrelevant to the engineering problem” (Shannon & Weaver, 1949: 3). However, his co-author Weaver (Ibid.: 116f.) observed in this connection:


                The concept of information developed in this theory at first seems disappointing and bizarre—disappointing because it has nothing to do with the meaning, and bizarre because it deals not with a single message but rather with the statistical character of a whole ensemble of messages, bizarre also because in these statistical terms the two words information and uncertainty find themselves to be partners.

                      I think, however, that these should be only temporary reactions; and that one should say, at the end, that this analysis has so penetratingly cleared the air that one is now, perhaps for the first time, ready for a real theory of meaning.


Brillouin (1962) argued in favour of a definition of ‘information’ as ‘meaningful information’ or ‘neg-entropy’. Reduction of uncertainty, or the meaningfulness of information, however, can only be defined with reference to a system. In general, a system can be defined as a unity that is able to retain information by updating.


Substantive theorizing enables us to specify a system of reference. Let us follow Luhmann (1984) in distinguishing between individual (psychological) systems and social systems as systems with potentially different dynamics for the update. Meaning assumes an operation over time by an operating system that is able to update in terms of repeatingly distinguishing between signals and noise. A second (time) axis for the selection is added to the selections at each moment. Since one could have provided the information with another meaning, one is also able to select among possible meanings, that is, using a third axis for this selection.


In general, selection is a recursive operation: some selections can be selected by a selecting system. For example, selections can be selected for stabilization. In a next round, the observable stabilizations can be considered as variations, but from the perspective of a next-order selecting system. Stabilizations can then be selected for globalization. Globalization can be considered as a consequence of the recursive selection by a next-order system. The higher-order systems build upon the lower-level ones by selecting among them.


Stabilization or codification is a system’s mode of operation; globalization takes place under the pressure of a (next-order) super-system. The initial selection underlying (potential) stabilization can be considered as subsystemic. Selection without stabilization remains subsymbolic. An identity is defined at a system’s level: it can be considered as a codified and, therefore, symbolic stabilization of the system, including its relation to the next-order system. For example, one can ask with hindsight whether a unity has remained the same while changing.


An identifiable system can be expected to develop along a trajectory, yet under selection pressure. At the subsystemic level of a network uncertainty is expected to prevail. The network structure operates at each moment, and under specific conditions this operation may develop into a system. A supersystem remains latent in the form of selection pressure on the systems and subsystems which are subsumed under it. Therefore, its operation can be considered as a global regime from these lower-level perspectives.


A self-organizing system is additionally able to select (in the present) among its selections and stabilizations using the additional degree of freedom of a global system for the internal reflection. Thus, one is able to distinguish between a system that is developing historically, that is, along a trajectory, and a self-organizing system which has one more degree of freedom for adjusting to its environments with hindsight. This super-system, however, exhibits itself only as the resilience of a regime with reference to its ‘instantiations.’


The selective operation can be used by a system to select upon the variations and selections of systems in its environment and internally, that is, on lower levels. When repeated over time, the selections generate couplings both horizontally and vertically (Simon, 1973). When the couplings can be stabilized, the communication channels can increasingly be considered as codifications of previous selections. The communication can thenceforth be used as a signal by the selecting system(s).



The probabilistic turn in communication theory


Communications can be volatile and, therefore, difficult to observe. However, one is perfectly able to measure communications in terms of change of the distributions. The notion of probabilistic entropy enables us to understand the mechanism of any system’s evolution using this communication-theoretical reflection. From this perspective, that is, from a perspective different from evolution theory, ‘variation’ and ‘selection’ can be considered as two sides of the same coin: the observable variation provides us with a description of the deselected cases. The system of reference for the selection remains to be identified as the hypothesis of the research design.


In other words: the concept of probability provides a common denominator for ‘selection’ and ‘variation,’ whereas these two operations were considered as independent in evolution theory. An empirical event can be expected to occur (with a probability); yet the occurrence of events remains uncertain because of selection pressure. There is randomness (variation) and determination (selection) operating. While in logic and mathematics one is able to deduce a consequence by making an inference, one can no longer expect to be completely certain (nor completely uncertain) in empirical domains.


Whenever a variation occurs that is not completely random, one selection or another can be expected to have operated. The variation could have been different. The two operations (variation and selection) are ‘structurally coupled’ in the events. Whether the result is to be considered as an observable variation or as a result of a (hypothesized) selection depends on the perspective of the analyst. The system of reference for the variation is different from that of the selection. In classical evolution theory, for example, variation occurs at the species level, while selection is attributed to nature as a super-system (that is, selection is defined as ‘natural’).


The two concepts of ‘variation’ and ‘selection’ can thus be considered as different geometrical perspectives on the algorithmic operation of generating probabilistic entropy. One needs an information calculus for the specification of this operation (Bar-Hillel, 1955; Leydesdorff, 1995). The notion of geometrical metaphors used for the communication, however, brings language into play. The perspectives can be considered as codified reflexively, that is, by using another selection for the stabilization of the picture.



The linguistic turn in the theory of communication systems


What does the information mean? Shannon’s mathematical theory of communication (implicitly) added a reflexive turn to the reception: the signal can be considered as a message which contains an expected information value. Upon reception, the signal can obtain an update value for the receiving system. The system which receives the message is able to provide the information contained in the message with meaning if this system is sufficiently complex for the reflexive reconstruction of the information contained in the message.


The observable variation can be considered as a distribution. The message that this distribution has occurred contains an uncertainty as its expected information content. The uncertainty is defined as ‘yet content-free,’ that is, content-free before the specification of a system of reference for the message. The specification of a system of reference provides the uncertainty with meaning.


The uncertainty expressed in bits of information is ‘not yet’ determined (Theil, 1972). One can determine it by choosing a system of reference, or in other words, by adopting a perspective. The uncertainty (i) is provided with meaning (j) by packaging it into a message (ij). A message is part of a language and thus language itself entails this reflexivity. The originally sent (Shannon-type) information i has to be reconstructed at the receiving end as i’ by decomposing the message with reference to its a posteriori meaning j’.


Languages enable us to codify the relation between the uncertainty and the meaning of a message. I deviate from Luhmann’s social systems theory by considering language as the operating system of society. Luhmann (1984) proposed that ‘meaning’ be considered as the operator of social systems. ‘Meaning’ is then considered as a (given?) precondition of both reflection and language (Luhmann, 1971). However, how this operator is constructed by the recursion of communication was not yet sufficiently reflected.


Meaning is generated interactively by using language. It can be considered as a reflexive function of language at the level of the social system (Pask, 1975). De Zeeuw (1993) has elaborated Pask’s paradigm by emphasizing that in a social science design “one has to look for ‘languages’ and ‘reports’, rather than for ‘laws’ and ‘facts’ ” (De Zeeuw, 1997). I submit that language is the evolutionary achievement which enables us to communicate using two channels for the communication at the same time: a statement can be provided with a meaning and it is expected to contain information.


The meaning of the communication can be codified and thereby provisionally stabilized, but it can also be changed (and exchanged!) with hindsight. Thus, the social system as the subject of cultural evolution is able to reconstruct its history continuously while operating reflexively and in a distributed mode. Both the uncertainty and the meaning provided can be communicated, and the decomposition between signal and noise can be revised accordingly, yet in an uncertain mode, that is, as a distribution of selections by micro-level agencies. In other words, the whole system doubles in the representation because the linguistic operation itself is dually layered.


Languages enable us to codify the meaning of the uncertainty in messages. This discursive reconstruction is a recursive operation which generates a multi-layered system endogenously. Lock-ins (in coevolutions) can emerge at each interface between two layers. Because of the recursion various layers can be involved and then there is an extending manifold of options for specific resonances. Cultural evolution can be considered as the uphill search for overtones in these interactions.



The human agents and their communicative competences


In addition to the ongoing exchanges of uncertainty and meaning, a third subdynamics of the communication is provided by the human carriers of the communication as far as they are competent and innovative in reconstructing and recombining the options provided historically. The contextual historicity of these communicative competencies provides the (super)system with another (that is, third) selection mechanism. Because the actors are socially distributed, the coevolution between the other two subdynamics (uncertainty and meaning) can be made uncertain. The super-system (that is, the relatively global regime), however, can only be built as next-order fragments on the observables, that is, the hitherto stabilized variation. Thus, the reconstructive capacities of reflexive and interactive agents become crucial to the further development of the social network system.


Insofar as the social system was first locked-in into a (cosmologically) given meaning, a high culture prevailed (Innis, 1950). Unlocking this social system requires communicative resources that reintroduce the uncertainties of what Habermas has called the ‘life-world’ into potentially new forms of codification. These new possibilities can be explored and perhaps stabilized in local niches, potentially to be selected for stabilization and globalization.


Cultural evolution once unleashed drives the communicative competencies of the carriers, and the reflexive recombinations undertaken by the latter remain a necessary condition for further evolution. Human beings and social communications can thus be considered as structurally coupled: what can be attributed as an action to a person can at the same time be considered as a communication between people. The inter-human communication can be codified using language.


Languages can further be codified into symbolic media of communication like money, power or trust. The symbolic media of communication enable us to shortcut and thus to accelerate the communication (Künzler, 1989; cf. Parsons, 1963a and b). Communication media can be developed insofar as they are functional to the organization of a society. Functionality, however, presumes a super-system. This social super-system was understood as a given ‘Nature’ during the individualistic revolutions of the 16th and 17th centuries. Upon its globalization in the late 17th century, the Newtonian cosmology legitimated processes of modernization and functional differentiation. The (super)system of reference, however, was defined as universal during the 18th century (Jacob 1988).


While “the book of nature” could be considered as universal and as a Given in the Newtonian cosmology, Darwin’s (1856) evolution theory introduced the notions of variation and ‘natural selection.’  From this perspective, ‘nature’ is considered as an operation, notably ‘natural selection.’ Only the consequences of this operation—the variation of surviving species—can be directly observed. Note that ‘selection’ has the epistemological status of an hypothesis. Evolution theory, for example, made it possible to conjecture a ‘missing link.’


From another perspective, Marx (1848) used the evolutionary metaphor to describe social selection processes. Although in his early writings selection by nature was not yet distinguished from selection by history, this distinction is crucial to his later ‘historical materialism’ (Marx, 1867). The two layers which were then labeled ‘production forces’ and ‘production relations,’ are expected to lock-in into a dialectics (Habermas, 1968).


When more than two subdynamics interact, the resulting dynamics (“trilectics” or “triple helix”) become complex (cf. Etzkowitz & Leydesdoff, 2000). The analytical specification of the systems of reference is then crucial. Whereas Parsons (1937) had considered ‘action’ as the unit of the system’s operation, Luhmann’s social systems theory provided a mirror-image of Parsons’s ‘structural functionalism’ by focusing on ‘interaction.’ According to Luhmann, the analysis of social structure should not be based on (the aggregate of) action, but on the interactions terms between actions. Interaction, however, constitutes a system of reference for the observable events that is different from action or its aggregates. The interaction terms can only be observed on the basis of an expectation.


Both Parsons and Giddens (and also Habermas, 1981) have attributed actions to interacting actors and/or aggregates of actors performing via institutions. Luhmann’s theory sides with symbolic interactionism by defining human action in terms of its interactive meaning at the network level (Blumer, 1969; cf. Mead, 1934). Linguistic acts, however, differ from performative actions in important respects (Searle, 1969). Luhmann (e.g., 1990) discussed this distinction in terms of the differences between experience (‘Erleben’) and action (‘Handlung’). These categories, however, were still defined anthropomorphically, that is, with reference to human agents.


The reflections at the sociological level are embedded in language (Searle, 1998) and, therefore, one should specify the differences between ‘reception’ and ‘change’ in terms of a theory of communication. A sociological theory of communication proceeds from meta-biological or meta-psychological perspectives by enabling us to consider the various positions (e.g., marxism, darwinism, structural-functionalism, etc.) as social texts, that is, as metaphors with specific (e.g., explanatory) functions. Social texts, however, can be deconstructed and gradually changed.


Language games and reflexive paradigms span universes with embedded codes. The codes suggest specific yardsticks for communications and expectations. Thus, the different universes are contingent and potentially incommensurable (Kuhn, 1962). In my opinion, this post-modern position has become a predicament (Bernstein, 1995). In terms of scientific inferences, however, the post-modern constellation does, in my opinion, not mean that ‘anything goes’ (Feyerabend, 1975) because the theoretical positions can always be specified. Yet, it means that all perspectives can be considered as specific, even if they entail universalistic claims.


From the perspective of a sociological theory of communication, Luhmann’s (1975) ambition to combine a general theory of society that integrates systems theory, communication theory, and evolution theory can be labeled ‘grandiose’ both in the positive and in the negative meaning of this word (Giddens, 1984, p. xxxvii). The tensions among the noted (three) general theories, however, can drive the empirical research programs of sociology because they can be expected to be reproduced. De Zeeuw’s major contribution, in my opinion, has been the reflexive turning of this tension to the construction of empirical designs.





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   [1] Luhmann (1975), at p. 96; the English translation is from Luhmann (1982), at p. 261.