[author]​LU Guoliang

[content]

Subject Critique in the Process of Communication: Revisiting the Intellectual Debate between Luhmann and Habermas

*Author: Lu Guoliang 

Doctoral Candidate 

School of Journalism and Communication, Shanghai International Studies University

Abstracts: Social theorists Niklas Luhmann and Jürgen Habermas engaged in a long-term intellectual debate in the last century, which attracted attention from numerous research fields. However, due to Luhmann's marginal status in the field of communication studies and the fragmented presentation of Habermas within it, this significant event has been forgotten in the long river of communication thought history, only scattered in a few studies. In response, this paper hopes to re-visit the intellectual debate between the two, presenting the philosophical thoughts on "communication" involved in the debate between Luhmann and Habermas, and exploring what core issues the two have been arguing about from the perspective of the history of communication thought. By revisiting the intellectual debate between Luhmann and Habermas in their important works during different periods, the article finds that: the intellectual debate between Luhmann and Habermas on "communication" is closely related to their core demands in criticizing the philosophy of the subject, and this intellectual contention actually focuses on the critique of the subject in the process of communication.

Key words: Niklas Luhmann; Jürgen Habermas; Intellectual Debate; History of Communication Thought;

1. Research Background and Problem Statement

Social theory giants Jürgen Habermas and Niklas Luhmann engaged in a long-term intellectual debate from the 1970s to the 1990s. The debate covered areas such as the theory of communicative action and systems theory, critical theory and functionalism, and academic values (Huang Zhengdi,2016). For communication studies, the most noteworthy aspect of this debate is the speculation on "communication" by Luhmann and Habermas. Habermas is well-known in the field of communication studies due to his affiliation with the Frankfurt School and his creation of the concept of the "public sphere." Although Luhmann's communication thoughts have been explored in a few communication studies in recent years, overall, they have not received sufficient attention in the field of communication research, which may be related to his "daunting" communication concepts (Bian Donglei,2016). In fact, Luhmann not only wrote a monograph on communication and mass media (Huang Dan,2020, but also regarded communication as the cornerstone of social theory (Huang Zhengdi,2016). In the preface of his posthumous work "Theory of Society", Luhmann stated outright: "Without communication, we cannot imagine society."  (Luhmann，2012：xiii)

Despite the intellectual debate between Luhmann and Habermas being present in philosophy, political science, and legal studies（Bing kai,2010；Huang zhengdi,2016；Houdun,2017）, and being closely related to communication thought, this event in the history of thought has not received enough attention from communication researchers due to the intersecting blind spots between these research fields and communication studies. The philosophical speculation on communication by Luhmann and Habermas in their debate is mostly presented in a fragmented form in existing research（Li Yufu, Cai Yukun，2012；Ge Xin，2012；Huang Dan，2020）. Only a few communication studies have focused on the conflict of their communication thoughts, defining the communication thoughts of Luhmann and Habermas as a conflict between "incommunicability" and "pursuit of commonality” (Bian Donglei,2016), but the underlying causes and specific processes of the intellectual conflict have not yet been presented and valued.

In other words, why did Luhmann and Habermas engage in intellectual contention around "communication" for decades? What theoretical demands are served by Luhmann and Habermas's unique interpretations and different understandings of communication? Is "incommunicability" and "pursuit of commonality" sufficient to summarize the intellectual debate? If not, what issues do Luhmann and Habermas's intellectual contentions on communication revolve around? What are their core demands? Obviously, to clarify the significance of the intellectual debate between Luhmann and Habermas in the history of communication thought, and to gain insights from their "communication" philosophy for current communication research, these questions cannot be avoided. Therefore, the following text, based on the main theoretical works in the process of the intellectual debate between Luhmann and Habermas, revisits their intellectual debate on communication from the perspective of the history of communication thought (see Figure 1).

2 The Beginning of Intellectual debate: Confrontation from “Communication” to “Subject”

As thinkers who grew up in the post-war German academic community, Luhmann and Habermas had a close relationship with the Frankfurt School. On the one hand, they inherited the Frankfurt School's responsibility for constructing social theory, and on the other hand, they were not satisfied with merely developing existing theoretical systems, attempting to establish a new type of social theory.

In the first phase, the intellectual exchange between Luhmann and Habermas culminated in the academic monograph The Theory of Society or Social Technology: What Does Systems Research Achieve (Theorie der Gesellschaft oder Sozialtechnologie: Was leistet die Systemforschung) published jointly by the two in 1971 (hereafter referred to as "The Theory of Society or Social Technology"). The book is divided into five chapters, with Luhmann explaining systems theory in the first and second chapters, followed by Habermas's critique in the third and fourth chapters, and Luhmann's response in the final chapter. The two can be said to be in sharp opposition. Luhmann began the book by advocating that systems theory is a reconstruction of the old European classical social theory (Habermas, Luhmann, 1971: 9), while Habermas remained skeptical about this. As the title "The Theory of Society or Social Technology" suggests, Luhmann and Habermas always revolved around a focal issue: whether systems theory is social theory or social technology serving the bureaucratic system. Luhmann stated in the preface of "The Theory of Society" that neither of them wanted their theories to be seen as social technology, but they had very different understandings of what social theory is (Luhmann, 2012: xi). According to Gorm Haste, the publication of this work was made possible by Habermas's students inviting Luhmann and Habermas to gather their disputes in one publication for academic appreciation (Haste, 2021: 57-58). Ultimately, Habermas and Luhmann engaged in fierce debates around numerous topics in the book, prompting both to construct more mature theoretical systems in the next phase. Although Habermas and Luhmann's theoretical systems were not yet mature at the time, both emphasized "communication," defending and questioning the self in relation to communication, such as Habermas acknowledging Luhmann's critique of the "transmission view," but opposing his interpretation of meaning. As the two took different critical paths in their philosophy of the subject, communication and the subject gradually became the core issues of contention.

The first two chapters of "The Theory of Society or Social Technology" consist of two articles by Luhmann, and his understanding of communication and the subject can also be seen here. Compared to many North American news communication researchers of the same period, Luhmann opposed the "transmission view," strictly distinguishing between meaning and information. Luhmann argued that the reason for the realization of communication does not lie in the mutual transmission of information between subjects as if it were a special substance, on the contrary, communication relies on the shared meaning infrastructure between subjects. The transmission view assumes that information remains unchanged as it moves between subjects, but in fact, "what plays the same role is not what is transmitted, but the shared meaning infrastructure" (Habermas, Luhmann, 1971: 42-43). The critique of the transmission view extends to Luhmann's questioning of the stability of the communication process. As communication is no longer assumed to be the continuous transmission of information between subjects, it appears in Luhmann's theoretical system as an unstable multiple-choice process (Habermas, Luhmann, 1971: 44). In this process, "meaning" is highly anticipated by Luhmann, seen as the common infrastructure that communication relies on, helping communication to be maintained in an unstable state.

Although Luhmann did not truly elucidate the three dimensions of meaning (the dimension of things, the dimension of time, and the social dimension)  until  in his foundational work in systems theory, "Social System," published in 1984,  in Chapter 2 of this book, "Meaning as a Basic Concept of Sociology," Luhmann, on the one hand, explains how meaning serves as a common foundational structure to support communication, and on the other hand, emphasizes the pivotal role of meaning in the daily operation of systems, criticizing the myth of subjective philosophy regarding the a priori attributes and subjective intentions (Habermas, Luhmann, 1971: 26-28, 61-62). Meaning is no longer merely a product based on the subject's intuition in subjective philosophy but is defined by Luhmann as "an order form in human experience, a prerequisite form for receiving information and consciously processing experience, and a form that can consciously understand and deduce high complexity" (Habermas, Luhmann, 1971: 61). On this basis, Luhmann criticizes the reduction of meaning by past scholars and refuses to equate meaning with action, because in his view, meaning is not limited to action, and confusing meaning with action can only lead to action being misidentified as the core factor of social constitution (Habermas, Luhmann, 1971: 62). In other words, in Luhmann's systems theory, meaning is superior to action, and all meaning originates from the system rather than from subject action, which constitutes a major difference between Luhmann and other systems theorists.

In response to Luhmann's interpretation of communication and meaning, Habermas offers a detailed critique in Chapters 3 and 4. Habermas agrees with Luhmann's critique of the "transmission view," but opposes Luhmann's assumption that communication is based on shared meaning structures (Habermas, Luhmann, 1971: 184-185). In Habermas's view, Luhmann's understanding of communication and meaning actually regresses to Husserl's phenomenological a priori self, ignoring the intersubjectivity that communication truly relies on (Habermas, Luhmann, 1971: 188). In other words, although Habermas does not agree with understanding communication as a simple transfer of information between subjects, he argues that communication is based on intersubjectivity, not on some a priori common meaning structure. The shared meaning structure that Luhmann speaks of is, in Habermas's view, based on consensus among subjects, otherwise it cannot be realized (Habermas, Luhmann, 1971: 203). Although Habermas has not yet systematically elaborated on the theory of communicative action, he has already emphasized in his critique of Luhmann that communication interaction is at the level of discourse rather than experience, and communication based on discourse is an important reason for the existence of society (Habermas, Luhmann, 1971: 214); if communication is unrelated to intersubjectivity, then communication cannot be realized (Habermas, Luhmann, 1971: 192). Habermas emphasizes that the action in the communication process is to refute Luhmann's approach that emphasizes meaning over action.

Why do Habermas and Luhmann have disagreements on the definition of meaning and action? On the one hand, the disagreement stems from the different views on language between Luhmann and Habermas. Habermas advocates that communication must be based on intersubjectivity at the level of language. This can be seen from the chapter immediately following Luhmann's, titled "Critical Preliminaries," which discusses communicative competence at length. Luhmann denies the precedence of language to thought, arguing that communication is not only based on the stable actions of language but is based on the unstable choices of double contingency (Habermas, Luhmann, 1971: 143; Haste, 2021: 78-79).

On the other hand, while differences in views on language are important, the deeper reason should lie in the different interpretations of communication and the subject by Luhmann and Habermas. Both are dissatisfied with the existing interpretations of the subject in Western subject philosophy, but their critiques of subject philosophy follow very different paths. Habermas has always insisted on verbal communication and intersubjectivity as the core of criticizing subject philosophy, which means that "human beings" (at least the rational beings emphasized by Habermas) as subjects have an indisputable dominant position. Here, this actually replaces the subject based on communicative and action capabilities with the subject of the objective cognitive paradigm (Wu Xingming, Lu Yingfu, 2018: 236-237), based on communication is seen by Habermas as the core to solving the dilemma of subject philosophy. In Luhmann's theoretical perspective, this has not yet escaped the myth of anthropocentrism (Haste, 2021: 61-62). Although Luhmann has long been criticized by Habermas as a representative of conservative theory, he is more radically critical of the "subject" than Habermas. As early as in his 1971 work, Luhmann had clearly rejected using humans as the theoretical starting point, advocating for systems as the basis for explaining society (Habermas, Luhmann, 1971: 326). In other words, the existence of society is not based on human action but is rooted in the operation of systems.

Luhmann's and Habermas's different definitions of the subject extend to their divergent interpretations of communication and meaning. Luhmann assumes that both communication and meaning are rooted in systems rather than humans, which is precisely where Luhmann differs from Habermas, as he views communication and meaning as existences above action. On the contrary, Habermas has always insisted that only intersubjective communication at the level of discourse can establish true subjects (rational subjects), and even the differences mentioned by Luhmann can only exist after intersubjective consensus is established (Habermas, Luhmann, 1971: 224). In Luhmann's view, Habermas's establishment of subjects based on intersubjective rational communication actually dissolves the contingent choices that accompany communication (Habermas, Luhmann, 1971: 326), and the so-called consensus only establishes communication on the basis of opinion convergence, which in turn negates the legitimization of "negation" in language (Habermas, Luhmann, 1971: 321-322). Combining the disagreements of Luhmann and Habermas on meaning and communication, Luhmann sees systems and environments as the core of communication operation and excludes people as subjects from communication, while Habermas still adheres to the anthropocentric concept of subjects, and the two inevitably place communication on different levels. Luhmann views communication as a bridge between systems and environments and sees meaning as an element of communication, while Habermas insists on the consistency of communication, meaning, and action, serving his trinity of intersubjectivity, speech acts, and rational subjects. In other words, it is not so much that Luhmann and Habermas disagree on whether communication is possible, but rather on different critical approaches to the subject during the communication process.

In order to achieve a critique of subject philosophy, Luhmann and Habermas deeply interpret communication, subjects, meaning, and truth during this period, addressing the important epistemological question of subject philosophy since Descartes, "How can the subject know the world?" Habermas has already regarded communication as the core to solving the above predicament. In an ideal communication environment, Habermas emphasizes that the subject's search for truth is based on the consensus established by intersubjective communication, and when communication is blocked, it is precisely the moment when ideology is born (Haste, 2021: 64). Therefore, the subject's understanding of the world stems from communication and consensus based on intersubjectivity, and ideology as a distortion of truth is a form of blocked communication (Haste, 2021: 61-62). In this regard, Luhmann believes that if Habermas incorporates intersubjectivity into communication, he needs to clearly establish discourse rules, but Habermas did not systematically elaborate on the relevant theories until the 1980s in his work "The Theory of Communicative Action."

At the same time, because Luhmann advocates that humans are merely the environment of communication, strictly distinguishing psychological systems from social systems, and placing communication at the social level for discussion, the subject that takes into account both psychological and social levels in traditional subject philosophy is deconstructed in the communication process. Luhmann transforms ontology into the constructivism of differences in epistemology. But how can systems establish themselves in a diverse world through communication? Luhmann's solution lies in "distinction," advocating that the establishment of systems is based on the distinction of the environment. Luhmann recognizes the existence of external reality, but observing reality can only be based on the distinction between systems and environments, and both systems and environments are constructed through "distinction" (Borghaus, 2016: 41), and the "boundary" constructed through distinction is based on communication for reproduction within the system. However, the above plan is still somewhat vague in Luhmann's thought during this period, because although Luhmann has paid attention to the important implications of meaning and communication for system and social interpretation, he has not completely free from the influence of Parsons' functional system theory, there is still a focus on the relationship between action and social construction (Zheng Zuoyu, 2022). This approach indeed allows systems theory to avoid the epistemological dilemmas of subject philosophy, but it also leads to another problem. How can a closed system maintain the unity of closure and openness? Luhmann failed to fully respond to Habermas' doubts, and it was not until the introduction of the concept of "autopoiesis" that he was able to reconcile his argument. In Habermas' view, Luhmann actually abandoned the critique of subjects and ideology, denying the knowability of truth (Habermas, Luhmann, 1971: 271). However, considering that Luhmann had already criticized Raymond Aron's ideology end theory as early as 1960s, and even regarded systems theory itself as an object of observation (Haste, 2021: 91), Habermas' moral critique is questionable.

Luhmann and Habermas, as great figures in social science, had already developed quite complex theoretical systems in the 1960s and 1970s. Based on "Social Theory or Social Technology," this article analyzes the debate between Luhmann and Habermas on communication, subjects, meaning, information, and truth. In this debate on social theory or social technology, Habermas focuses on the legitimacy crisis of society, while Luhmann is more concerned with the theoretical crisis in social research (Bolz, 2010). The former tends to critique society to guide it in a specific direction, while the latter hopes to form effective explanations based on current society. In this, communication and subjects become the core of the debate between Luhmann and Habermas. Although Luhmann and Habermas interpret communication in different ways, they both pay attention to the central position of communication in social theory and social practice, and hope to critique subject philosophy by reinterpreting the relationship between communication and subjects. Compared to North American communication researchers of the same era, Luhmann and Habermas clearly reject the transmission view and attach great importance to the social implications contained in communication. The ideological confrontation allows Luhmann and Habermas to discover their respective theoretical construction paths. For example, although Habermas criticizes that Luhmann's systems theory cannot take into account both the theoretical and empirical levels (Habermas, Luhmann, 1971: 278), he also constructs his version of the system (relative to the lifeworld), integrating it into the theory of communicative action.

Overall, in the first phase of the debate, Luhmann distinguishes between meaning and information, emphasizing meaning as the basic structure of communication, but does not deny the possibility of communication. On the one hand, he rejects the reduction of communication to the transmission of information, and on the other hand, he opposes Habermas' excessive praise for language (Huang Zhengdi, 2016). By distinguishing meaning, communication, and action, Luhmann opposes the previous scholars' view that only observable actions are communication, but he does not deny communication. Habermas is not criticizing Luhmann for ignoring communication, but criticizing Luhmann for assuming that communication is based on shared meaning structures (Habermas, Luhmann, 1971: 184-185), neglecting intersubjectivity and verbal communication. Of course, Luhmann and Habermas have differences on "consensus," but limiting their intellectual debate on communication to this may be shortsighted.

Combining their different interpretations of subjects and communication, the ideological debate between Luhmann and Habermas at this time focuses on the critique of subjects in the process of communication. Habermas inherits the humanistic thought since Kant (Moeller, 2011: 37), always imagining and communicating around human with richly enlightenment; Luhmann rejects the starting point of communication as human, instead, he regards humans as the environment of communication (unable to directly form a connection with the communication as system), and discusses communication within the social system. This divergence of thought on communication and subjects extends to issues of meaning, action, information, and truth. Given that both Luhmann and Habermas' theoretical systems have changed after the first phase of the debate, and they published foundational works of their theoretical systems in the 1980s ("Social Systems" and "The Theory of Communicative Action"), analyzing only the first phase of the ideological debate is not sufficient to present and interpret their ideological debate and theoretical demands on "communication." The following text will further explore how the two formed ideological dialogues around communication after the establishment of their theoretical systems.

3 The Climax of the Debate between Luhmann and Habermas: Subject Critique in the Process of Communication

Following the publication of " Social Theory or Social Technology," Luhmann and Habermas continued to deepen their respective theories. Habermas published his magnum opus, "The Theory of Communicative Action," in the 1980s, elaborating on the theory of communicative action in detail; Luhmann also published his seminal work, "Social System," during this time, introducing the unique biological concept of "autopoiesis" into systems theory, completing his general social theory pursued throughout his life.

Although Luhmann and Habermas did not publish a monograph together based on their intellectual debate again, theoretical critiques can still be found scattered throughout their important works. Habermas cited Luhmann's systems theory in "The Theory of Communicative Action" and "The Philosophical Discourse of Modernity," providing extensive commentary; Luhmann, on the other hand, occasionally directly or indirectly critiqued Habermas in his works. Here, the discussion of communication and the subject has become increasingly important in both of their theoretical systems. Habermas advocates for transcending the a priori subject dilemma through communicative action and intersubjectivity, considering communication between subjects as the cornerstone of the lifeworld; Luhmann radically uses the concept of the autopoietic closed system as the theoretical basis, thoroughly deconstructing the concepts of subject (object), and transforming ontology into a constructivism of differences in epistemology. In other words, with the establishment of new theoretical systems, the intellectual debate between Luhmann and Habermas gradually reached its climax. As Habermas stated in "The Philosophical Discourse of Modernity," the confrontation between intersubjectivity and the closed system has replaced the traditional "mind-body" problem (Habermas, 2011: 430).

Luhmann and Habermas faced some theoretical challenges in the first phase, which gave rise to the theoretical development in the second phase. For Habermas, there were two challenges in the first phase: the vagueness of discourse rules and the integration of systems and the lifeworld. Habermas emphasized in "Social Theory or Social Technology" that communication is based on intersubjectivity (Habermas, Luhmann, 1971: 192), criticizing Luhmann for wrongly assuming the meaning of communication as an a priori shared structure, because meaning is rooted in the consensus reached through intersubjective communication (Habermas, Luhmann, 1971: 203). However, Luhmann pointed out sharply that if Habermas were to integrate intersubjectivity into communication, clear discourse rules would need to be established (Haste, 2021: 79-80). In other words, although Habermas hoped to establish a stable association between intersubjectivity and communication through language, his argument was still vague and did not clearly explain which rules language uses to ensure the consistent association of intersubjectivity and consensus in communication.

Furthermore, although Habermas criticized Luhmann's approach of replacing subjects with systems to solve the dilemma of subject philosophy as lacking critical awareness, he acknowledged that systems have theoretical potential, but systems should be constructed in relation to intersubjectivity and linguistic communication, which he himself has not yet fully elaborated (Habermas, Luhmann, 1971: 278). At the same time, Luhmann also faced two major challenges in the first phase. On the one hand, although Luhmann reinterpreted communication by distinguishing between meaning and information in "Social Theory or Social Technology", he did not fully explain the interactive mechanism among meaning, communication, and systems. On the other hand, Luhmann established the rules defining systems through the distinction between systems and environments, but as Habermas's criticism showed, Luhmann still needed to explain how closed systems can achieve interaction and how systems can cope with the increasing complexity of society (Habermas, Luhmann, 1971: 158).

Faced with the above challenges, Habermas and Luhmann responded by constructing or introducing new concepts. In "The Theory of Communicative Action (Volume 1): Rationality of Action and Social Rationalization," Habermas systematically explained the language rules associated with communication based on intersubjectivity. Habermas divided human actions into purpose-oriented instrumental actions and strategic actions, as well as communication-oriented communicative actions (Habermas, 2018: 360-361), defining communication as "the process by which subjects capable of speech and action reach an understanding with each other" (Habermas, 2018: 362). Therefore, to understand communication between subjects, one needs to consider speech patterns (Habermas, 2018: 363), which means that the rules of communicative action urgently need to be clearly explained. In "The Theory of Communicative Action (Volume 1)," by critiquing the pragmatics of Austin and Searle, Habermas established formal pragmatics and established three types of speech acts: regulative speech acts, performative speech acts, and constative speech acts (Habermas, 2018: 399). Habermas integrated speech acts into a larger system of actions: teleological actions, speech acts, dramaturgical actions, and dramaturgical actions, thereby establishing the association between actions involved in communication between subjects and the lifeworld and systems (Habermas, 2018: 416-418).

At the same time, on the one hand, Habermas criticizes Dieter Henrich's attempt to rescue the instrumental rationality of subject philosophy through "self-defense" as merely falling into the quagmire of systems theory again (Habermas, 2018: 486-489). On the other hand, he criticizes Luhmann and other systems theorists for underestimating language and not realizing the deep involvement of the structural characteristics of language in communication (Habermas, 1987: 261). It can also be found in another magnum opus, "The Philosophical Discourse of Modernity," that Habermas' ultimate appeal in establishing the connection between language and communication lies in replacing the subject of the objective knowledge paradigm advocated by subject philosophy with a subject based on linguistic and action capabilities, in order to address the crisis of subjectivity and modernity (Wu Xingming, Lu Yingfu, 2018: 236-237).

In "The Theory of Communicative Action (Volume 2)," Habermas constructs his unique understanding of systems and the lifeworld by critiquing the thoughts of Luhmann, Luckmann, and Schutz on systems and the lifeworld. In his view, although Schutz and Luckmann's phenomenological approach avoided the neglect of intersubjectivity in traditional subject philosophy, they are still confined to subject philosophy. This is because both, while emphasizing the importance of intersubjectivity for the lifeworld, did not take intersubjective communication as the cornerstone of the lifeworld construction, but rather returned to Husserl's envisioned a priori subject, thus being confined to the a priori subject presupposition at the level of consciousness (Habermas, 1987: 129-130). In other words, intersubjectivity based on speech has not been given importance in previous interpretations of the lifeworld. Here, Habermas uses Luhmann's systems theory as a contrasting theory to criticize Luckmann and Schutz, pointing out that the lifeworld they envisioned is easily replaced by systems theory, and such a replacement would have endless consequences (Habermas, 1987: 129-130). In fact, due to its radical constructivist approach, Luhmann's systems theory is often regarded by social constructivist researchers as a radical variant (Eberle, 2023).

In contrast to Luhmann, who takes systems as the starting point for explaining the world, Habermas only incorporates the operational organizations of the economy and politics into systems, emphasizing that the lifeworld contains a large number of cultural characteristics, and the reproduction of structures can only be based on communicative action (Habermas, 1987: 261). In this context, Habermas criticizes Luhmann's envisioned autopoietic system as actually being a reification of the lifeworld, disregarding culture, society, and individuality, and neglecting the power struggles involved in social operation (Habermas, 1987: 307-309). In Habermas's view, the autopoietic system assumes that "the lifeworld constructed on symbols has given way to a self-sufficient social system" (Habermas, 1987: 311), and the bleak situation of capitalist society as Weber described is precisely the thorough colonization of the lifeworld by systems (Habermas, 1987: 311-312).

Habermas's conception of communication, systems, and the lifeworld is closely related to his long-standing slogan of "saving society." Unlike Luhmann, Habermas focuses on finding rational solutions to the crises of modern society. In Habermas's theoretical system, the trends of systematization and instrumentalization of modern society are undoubtedly severe social crises (Bolz, 2010), and the concept of the lifeworld, which has been transformed by Husserl, Schutz, and Luckmann, is endowed by Habermas with the heavy responsibility of resisting this trend. As elements such as tools, power, and control are thrown into the system, communication in the lifeworld is fascinating, it is conceived as being based on communicative rationality, in line with moral norms, and unrelated to the system, which inevitably becomes an intoxicating idyllic conception (Bolz, 2010). However, regardless of the utopian color of the above ideas at the empirical level, does the system, which Habermas sees as the other side, also reduce the complexity of everyday life? Habermas defines the relationship between communicative action and the lifeworld by explaining discourse regulations and types of action, but the involvement of non-linguistic symbol systems and material objects intervene in communication and social construction is not valued in the theory of communicative action (Knoblauch, 2020: 64). Habermas, inheriting the humanistic tradition, inevitably faces the question of whether to simplify the material and spiritual dimensions of communication in the lifeworld into the dimension of discourse when discussing communication in the lifeworld.

In contrast to Habermas's critique of systems, Luhmann has always firmly taken systems as the basis of social theory. In his foundational work of systems theory, "Social System," published in 1984, Luhmann introduced the concept of autopoiesis from biology to respond to theoretical criticism and further elaborate on systems theory. In the book, Luhmann uses autopoiesis and structural coupling, along with an alternative interpretation of communication, to explain how systems can remain closed on one hand and open on the other, achieving self-reproduction (Luhmann, 2021: 217, 266). Self-referential systems achieve self-observation and self-reference through their own operations, and then, by leveraging the structural coupling between systems, use meaning as a bridge to achieve unity between closure and openness (Luhmann, 2021: 221, 266). In the social system, communication places the difference between the system and the environment within the system, reproducing the boundary between the system and the environment (Luhmann, 2012: 42). In other words, the closure and openness of systems are conditional upon each other, the closed operation of a system does not merely reduce or increase the complexity of the world but does so simultaneously (Huang Zhongdi, 2016). For this, we might take the mass media system we are familiar with as an example. Different from the traditional perspective, the mass media system under systems theory, as an autopoietic system based on specific codes (information and non-information), operates autonomously in a closed manner. However, the mass media system is not detached from social reality, on the one hand, it constructs reality through "observation," and on the other hand, it is observed and constructed by other systems, thus achieving unity between closure and openness (Huang Dan, 2020).

Although Luhmann is criticized by Habermas (1987: 307-309) as being anti-humanistic, Luhmann's replacement of the subject-object dualistic difference with the system-environment difference does not mean that he completely abandons humans in social theory, nor does it deny the ubiquitous human practices in daily life (Luhmann, 2012: 12). Faced with Habermas's accusation of being anti-human, Luhmann believes that not starting with humans as the basis of social theory does not mean that social theory needs to be anti-human, but rather establishes the theoretical foundation of social theory at the theoretical level (Luhmann, 2012: 12). In Luhmann's systems theory, humans as the environment of the system do not mean that humans are unimportant (Moeller, 2006: 8). Given the mechanisms of structural coupling and interpenetration, humans as the environment are not secondary to the system; the environment regulates the establishment and operation of the system. When Luhmann traces the history of the "individual," he points out that until the 18th century, the individual was still a "thing" concept, and the essence of the individual as rationality was only a special case (Luhmann, 2021: 308). Habermas assumes individuals to be individuals who participate in communication based on mutual understanding and sets many discourse rules; but in reality, without any coercion, would the self and others really spontaneously take on the various uncertainties of the communication process (Luhmann, 2021: 308)? In other words, if Habermas relies on rational individuals to resolve the deep-rooted "individual-collective" contradiction in social theory, understanding the community merely as a partial fusion of individuals and society actually eliminates the distinction between system and environment, retreating back into the predicament of subject philosophy (Luhmann, 2021: 267, 308). Therefore, the evolution of social structure cannot be attributed to the individual level; structural changes to be realized require systems through communication (Luhmann, 2021: 409).

Given that communication is considered the core of systems theory, Luhmann comprehensively elaborates on communication theory in "Social System." He continues the critique of the transmission view from "The Theory of Society or Social Technology," strictly distinguishing between information and meaning, and emphasizing that meaning is fundamental to communication (Luhmann, 2021: 117). Luhmann differentiates meaning into the dimension of content (Sachdimension), the dimension of time (Zeitdimension), and the social dimension (Sozialdimension), and these dimensions of meaning maintain the operation of systems at various levels (Luhmann, 2021: 117, 120). Under the dimension of content, things are differentiated by meaning into "there" and "here" (Luhmann, 2021: 121), which is reflected in the differences of communication themes in social systems and the differences of perceptual objects in psychological systems. The dimension of time is based on the past and the future, and the system of meaning is constituted by the present without a beginning or an end based on this difference (Luhmann, 2021: 122-123). "Meaning" is then based on the temporal dimensions constructed by the system from different observational perspectives. The social dimension concerns the difference between the self and the other, advocating that meaning is based on the differences in the observational horizons of the self and the other at the social level, that is, meaning in the social dimension is based on double contingency (Luhmann, 2021: 124-125; Baraldi, Corsi, Esposito, 2021: 142). Combining the dimensions of content and time, the social dimension escapes the confused situation where subject philosophy has to simultaneously refer to sociality, temporality, and materiality when involving meaning in the communication process; in other words, meaning does not need to be attached to the subject but is based on the double horizons of different dimensions, avoiding the sociality of meaning regressing to an atomic-like subject (Luhmann, 2021: 126). "This means that everything done by the theory of (Habermas-style) intersubjectivity founders here" (Luhmann, 2021: 127).

Building on this, Luhmann introduces the concept of double contingency and breaks down communication into unstable forms that accompany choice: information, notification, and understanding. The "trichotomy" of communication is not originally from Luhmann; Luhmann also acknowledges that similar trichotomies can be found in the works of Buhle, Austin, and even Habermas (Luhmann, 1992). However, the difference lies in the fact that they all view communication as the action of the subject, assuming that communication is whether the successful transmission of information is achieved or not. On the contrary, Luhmann always emphasizes the instability of communication, where every choice is accompanied by contingency, and communication realization belongs to double contingency; communication itself reproduces communication, not the action of the subject. Therefore, communication itself has no goal to speak of, nor can it be said to end; it is just that Habermas misunderstands communication as an action that ends with consensus (Luhmann, 1992). In fact, communication does not need consensus and can even be self-contradictory because paradoxical communication is also meaningful to the observer (Luhmann, 2012: 49). Compared to Habermas's lifelong pursuit of consensus, in Luhmann's view, "communication only begins when information and notification actions are observed as differences and give rise to the next step of choices" (Luhmann, 2021: 188). In other words, the communication envisioned by Habermas still starts with the subject and tries to use communication to solve the epistemological problems of subject philosophy. However, essentially, if communication ends with intersubjective consensus, communication can only be limited to the verbal actions of the subject, which inevitably strips the rich connotation of communication and reduces it to a linguistic variant of Parsons's action theory. Luhmann does not believe that people cannot observe communication in daily life but emphasizes that these observations are actually rooted in "action" rather than "communication" (Luhmann, 2021: 210-211). In connection with the three forms mentioned above, communication is a comprehensive choice based on differences, and action is actually the attribution of communication (Luhmann, 2021: 221-222). The social system can only attribute the communication found at the observational level to a series of actions, and communication cannot be traced back like action because "communication cannot be directly observed, but can only be inferred" (Luhmann, 2021: 210-211).

By reinterpreting the various elements of communication, Luhmann constructs a communication theory in "Social System" that is different from conventional understanding. But why he risk being misunderstood as negating communication and go to great lengths to construct a counter-intuitive communication theory? In Luhmann's view, if communication and action are not distinguished, then communication, which contains a series of uncertain choices, would be simplified into a linear and monotonous chain of actions (Luhmann, 2021: 210). In the operation of social systems, communication is precisely the process of placing the differences between the system and the environment within the system for self-reproduction, thereby achieving the system's self-observation and reference (Luhmann, 2012: 53). Therefore, if communication and action are confused, the operation of psychological systems and social systems would be indistinguishable, and we would have to fall back into the subject predicament of the mind-body dualism. In fact, Luhmann also tried to explain society by considering action as the basic element of the system, but after several attempts, he still ran aground (Zheng Zuoyu, 2022). He then strictly distinguished communication from action and regarded communication as the only mode of social operation (Luhmann, 2012: 42).

This also involves Luhmann's thinking about the interconnection between the subject and the world. Although Husserl, Schutz, and Habermas have successively attempted to explain the sociality of the subject and the construction of society based on intersubjectivity, communicative action, and consensus, in Luhmann's view, this only puts the problem back into the vague "culture" again, still lacking sufficient explanation (Luhmann, 2021: 151-152). In response, Luhmann radically abandons the subject and turns to discuss this issue from the three main systems: "psychological system," "social system," and "physiological system." From the perspective of systems theory, "it is not the world that determines the meaning of the system, but the system that determines the meaning of the world, and thus its reality" (Moeller, 2006: 71). Traditional communication theory naturally cannot match this, because action originates from the social system, and the social system needs an indivisible element for itself as the foundation for construction (i.e., communication as defined by Luhmann). Communication must be independent of action; communication exists as the constructive level of the social system, while action is only established at the observational level, helping the social system to reduce complexity (Luhmann, 2021: 184-185).

In summary, Luhmann and Habermas have established grand theoretical systems during this period. In the process of constructing their respective theories, they responded to criticism on one hand, and on the other hand, they incisively pointed out each other's shortcomings. Although Luhmann and Habermas had fierce debates around communication, their theoretical appeals mainly concern different critical paths in subject philosophy. Indeed, the communication theory constructed by Luhmann during this period defies common sense, strictly distinguishing between communication and action, and negating communication at the observational level, but Luhmann did not deny the possibility of communication, nor did he ignore everyday communication (in his view, this should be action, and its core is communication). Habermas's critique of Luhmann's view of communication is not about "denying communication," but rather about Luhmann's underestimation of the unique significance of language in communication.

In fact, Luhmann and Habermas continue the core of the first phase of their confrontation: critically examining the subject in the process of communication from different paths. After introducing the concept of autopoiesis, Luhmann quite comprehensively explained how social systems achieve the unity of closure and openness through meaning and communication in the interpenetration with other systems. Habermas also replaced the objective recognition paradigm subject of consciousness philosophy with the communicative subject after establishing speech rules (Wu Xingming, Lu Yingfu, 2018: 237-239). Luhmann and Habermas form quite different critiques of the subject in the process of communication, which constitutes the core issue of ideological contention. Whether it is "The Theory of Communicative Action" or "The Philosophical Discourse of Modernity," Habermas criticizes Luhmann's substitution of systems for subjects from the theoretical content and ideological levels in his monographs. In his view, taking systems as the basis of social theory can avoid the difficulties of subjective and objective idealism at the metaphysical level, but this has actually shifted from metaphysics to meta-biology, which is essentially a retreat from the critique of rationality (Habermas, 2018: 413-416). Luhmann still criticizes Habermas's overemphasis on rationality in his important work "Social Theory" before his death, and points out through the history of rationality that the premise of social theory must be based on individual rationality, which is precisely the blind spot of humanists (Luhmann, 2012: 100-102), because communication theory does not need to take rationality as a core element (Luhmann, 2012: 120). When Luhmann wrote the preface for "Interpreting Luhmann: An Introduction to Systems Theory's Keywords," he advocated that the society of the Enlightenment period has long passed, and various value standards as the basis of rationality have dissolved, and the current task of scholars is to depict society (Baraldi, Corsi, Esposito, 2021: 13).

As Bing Kai mentioned in the preface to the translation of Luhmann's "Sociological Theory of Law," "While Habermas claims to continue Kant's 'project of enlightenment,' Luhmann, in contrast, claims the 'enlightenment of sociology'" (Luhmann, 2013: 4). Habermas and Luhmann have chosen entirely different critical paths to reflect on subject philosophy, but both have unanimously placed communication at the core of their respective critical paths. The different interpretations of the subject in the process of communication naturally become the focal point of criticism and an eternal theme of intellectual contention.

4 Epilogue: The Echoes of Intellectual Debates

As stated at the beginning, this article does not aim to draw a conclusive conclusion by revisiting the intellectual debate between Luhmann and Habermas. Instead, it hopes to present the communication ideas involved in the decades-long intellectual debate between Luhmann and Habermas, to explore from the perspective of the history of communication thought what core issues Luhmann and Habermas have been arguing about for decades, and where their theoretical appeals are directed.

Although Luhmann has been labeled with "incommunicability" by existing research, revisiting the decades-long intellectual debate between Luhmann and Habermas shows that both, in their early and mature theoretical periods, regarded communication as the cornerstone of social theory and did not form a debate based on "whether communication is possible or not." Luhmann's communication thought system is counterintuitive, closely linking communication with systems and environments (rather than human subjects), and advocating that communication cannot be directly observed and can only be attributed to actions. So, does Luhmann, who advocates systems, really deny human communication? Indeed, "Humans cannot communicate, only communication can communicate" (Luhmann, 1996) is a famous assertion by Luhmann about communication, but this assertion should not be viewed in isolation and should be understood within the framework of systems theory. As shown earlier, Luhmann, unlike Habermas who promotes the Enlightenment tradition, radically stops explaining based on humans as subjects when dealing with the interconnection between subjects and the world, advocating that systems determine the meaning of the world (Moeller, 2006: 71). In this, the reason for the formation of society is no longer based on the consensus, shared values, and harmonious unity of the lifeworld advocated by Parsons and Habermas, but on the self-reference of social systems to their own differences with the environment (Luhmann, 2012: xiv). The self-reference of social systems relies on communication. Recursively closed social systems operate based on communication and form structural coupling with psychological systems and physiological systems through meaning, placing differences within the social system to regenerate the boundaries between the system and the environment, achieving autopoiesis (Luhmann, 1996).

Furthermore, although Luhmann takes systems as the starting point for social theory, he does not ignore the human practices in daily life (Luhmann, 2021: 210-211). By considering humans as an important environment for the operation of various systems, Luhmann is not denying humanity but pursuing diversity, thus abandoning the humanist illusion of uniting body, mind, and communication (Moeller, 2006: 98). With communication as a core element of the social system, Luhmann avoids confusing communication with action because daily communication should be attributed to action at the observational level, not communication itself; the latter should be understood as a pure synthesis of choices, assisting the system in achieving self-observation and self-regeneration (Luhmann, 2021: 221-222). This is not anti-humanism but a theoretical requirement for constructing social theory (Luhmann, 2012: 12). In this regard, one might refer to Luhmann's famous haircut joke: If society is made up of people, then does a person going to a barbershop and getting a haircut remove some parts of society (Boghaus, 2016: 86)? As Bolz said when evaluating the anti-humanist tendency of Luhmann's systems theory, "Only a thoroughly anti-humanist theory can take individuals seriously; expelling people from sociology, in turn, creates space for many individuals" (Bolz, 2010). Combining the theoretical appeals of both, the critique of the subject in the process of communication is where the deep contention lies in the intellectual debate between Luhmann and Habermas. From the early co-authored "The Theory of Society or Social Technology" to the later theoretical masterpieces "The Theory of Communicative Action," "The Philosophical Discourse of Modernity," "Social System," and "Social Theory," Luhmann and Habermas have always explored how to break through the subject predicament of subject philosophy based on communication and reshape social theory. In response, Habermas's answer is a rational subject based on linguistic and action capabilities. While Luhmann more radically eliminates the subject, grounding social theory on systems and their environments. Although the two have chosen very different critical paths, how to critique and reconstruct the subject in the process of communication remains the focal point of their critique of subject philosophy.

Furthermore, revisiting the confrontation between Luhmann and Habermas on the subject of communication from the perspective of the history of communication thought, what insights does it offer for communication studies? The thinking of Luhmann and Habermas on the subject is highly subversive to social sciences (Huang Zhongdi, 2016), and revisiting their intellectual debate helps us shift our focus from "whether communication is possible" to the critique of the subject in the process of communication, thereby gaining a deeper understanding of their communication thoughts. In terms of Habermas's contribution to communication research, existing studies have pointed out that Habermas's intellectual system is often presented in a fragmented manner, with the concept of the public sphere appearing in a large number of communication studies, but other theoretical concepts are still less favored by communication researchers (Su Jing, 2018). Starting again from Habermas's most fundamental thoughts on the subject of communication should be an important path for communication researchers to comprehensively understand Habermas. In contrast, in the field of local journalism and communication research, the few discussions about Luhmann often refer to his anti-humanism and incommunicability (Li Yufu, Cai Yukun, 2012; Ge Xing, 2012; Bian Donglei, 2016). Due to Luhmann's long-term neglect in the North American academic community, which emphasizes humanistic traditions (Moeller, 2011: 32), local research, deeply influenced by the North American academic community, cannot help but keep a respectful distance from the abstruse Luhmann. Therefore, for various reasons, the local academic community has not paid enough attention to the rich implications of Luhmann's systems theory for communication research. In fact, Luhmann's subversive thinking on communication and the subject can form a highly academically tense theoretical dialogue with the current trend of "material turn," such as non-human communication (Jansen, 2016), and mediatization theory (Kunelius, Reunanen, 2016). As Huang Dan said when evaluating "The Reality of Mass Media," "It is in this sense that Luhmann has pried loose the existing foundations of the journalism and communication discipline" (Huang Dan, 2020).

Although the critiques and debates of the subject of communication by Habermas and Luhmann originated in the context of traditional media, in today's era of smart media prevalence, the critique of the subject in the communication process has become increasingly important. From AlphaGo to ChatGPT, new types of artificial intelligence have prompted the academic community to re-examine the role of media technology objects in communication phenomena. In this context, new theories related to the materiality of media have emerged in recent research, such as Hepp's mediatization theory and Kittler's media ontology. While these new theories critically examine the relationship between humans and media, they also point to a crisis of the subject of communication. In fact, whether it is the interaction between humans and artificial intelligence or between artificial intelligences, it has not escaped the realm of communication. Building on the previous text, the discussion of the "human-media" relationship needs to return to the "meta-questions" of communication and the subject. In this regard, Habermas and Luhmann's critiques of the subject in the communication process are enlightening in terms of ontology and epistemology. The contemplation of the "subject-object" relationship between humans and media in the communication process can form a theoretical dialogue with the intellectual resources of their critiques of the subject. For example, media materiality research often emphasizes the subject attributes of media in the communication process. If viewed from the theoretical perspectives of Habermas and Luhmann, this may not have escaped the epistemological predicament of the a priori subject, still deeply entrenched in the dichotomy of subject and object. Combined with recent research on the communication process between humans and media (Bolin, 2024), Luhmann and Habermas's different interpretations of communication and action also provide new perspectives on whether to view communication and action as one or to strictly distinguish between the two, which has become a complex and important issue in current research that increasingly emphasizes the subjectivity of media. Of course, the most direct change is in the "questions" asked. As questions are the "concentrated expression of the researcher's own insights" (Huang Dan, 2020), changes in the angle of questioning give rise to new understandings of empirical phenomena. For instance, starting from Luhmann's critique of the subject of communication, common questions about artificial intelligence as a subject (or object) in communication can be transformed into "how artificial intelligence operates as a system," breaking free from the shackles of subject (or object), and recognizing empirical phenomena from a completely different perspective.

Due to space limitations, this article cannot cover all aspects of the insights that Habermas's and Luhmann's grand theoretical systems offer to communication studies. The aim is simply to re-visit, from the perspective of the history of communication thought, the decades-long intellectual debate between the two, to explore the core of their confrontation and their theoretical demands, and to provide an "entry point" for more scholars to consider communication research based on the thought systems of these two masters.