Luhmann, N. (1968), Vertrauen - Ein Mechanismus der Reduktion sozialer Komplexität, Stuttgart: F. Enke Verlag.

Trust is a fundamental aspect of social life, and its absence can lead to paralyzing fears.

People understand trust differently. Some derive rules for proper conduct to maintain trust and some use their imagination to portray anxieties without trust.

The world's complexity affects human adaptation. Complexity blurs the distinction between psychological and sociological theories. Human beings are conscious of the world's complexity and can select their environment. The presence of other individuals introduces a higher level of complexity due to intersubjectivity. Trust helps reduce complexity and increase possibilities for experience and action.

Trust involves anticipating the future and behaving as though the future were certain. While ethics might recommend trust as a way to overcome the passage of time and approach eternity, the concept of time is complex and cannot be easily reduced to a linear flow or measure of movement.

Constancies and events are involved in an interplay. Trust is concerned with the future horizon of the present, attempting to envisage the future while maintaining a connection to the present. Trust is a way of dealing with the uncertainty of the future and reducing complexity.

The distinction between focusing on future goals and stabilizing the present highlights the dilemma between planning for the future and ensuring present security. Trust helps navigate this dilemma. Complexity generated by scientific and technological development will increase the demand for trust as a means of enduring an uncertain future.

The intentional structure of human experience sets limits on what can be understood at any given time. The movement of experience allows for the reduction of complexity, and this is achieved through an intersubjective process. The anonymous constitution of meaning and world forms the familiar basis for understanding, and this familiarity is the precondition for both trust and distrust. Familiarity is the background against which trust and distrust emerge. While familiarity does not inherently entail positive or negative expectations, it provides the conditions for committing to certain attitudes toward the future. Trust reduces the complexity of the future by assuming certain possibilities and taking the risk of defining the future based on past experiences. Trust and familiarity complement each other, and their relationship shifts based on the complexity of social systems and their changing relationship with time.

As complexity grows, trust evolves from being primarily emotional to being more performance-based. System trust involves extending trust to social and personal systems, necessitating a balance between risk-taking and control of outcomes. Trust adapts to increasing complexity and may involve a shift in its underlying basis.

Trust is a mechanism for reducing the complexity of decision-making in a complex world. Trust is like an advance payment, allowing individuals to choose actions even when faced with overwhelming complexity. Trust is a means to navigate uncertainty and adapt to rapidly changing situations. Trust is involved when there's a critical alternative, where the harm from a breach of trust could outweigh the benefit of trust being warranted. Trust is not mere hope; it involves taking a calculated risk based on the anticipation of others' actions. Trust allows for cooperation, coordination, and rational action by assuming that others will fulfill their roles or commitments.

Trust is learned through experiences, particularly in early life, and it can be based on internal certainty rather than external guarantees. The internal ordering of data-processing reduces complexity and increases tolerance for uncertainty. Trust can be projected onto the environment, leading to a sensitivity to disturbances and symbolic controls. The withdrawal of trust can be triggered by crossing certain thresholds.

Trust is a mechanism to manage complexity, but it remains a complex and ongoing issue itself. Trust doesn't offer a ready-made solution but acts as a substitute formulation for the original problem of complexity. The relationship between trust and complexity is dynamic, and the conditions and challenges of trust remain open questions.

Trust is built upon a foundation of limited information, and individuals willingly overcome this deficit by shifting problematic aspects from the external environment to internal modalities of learning and symbolic control. The objective world is more complex than any system, leading to the development of a subjective image of the world. Trust relies on a certain degree of familiarity and knowledge about the other party, allowing individuals to make assessments and judgments about whether trust is justified. Trust involves assessing potential gains and losses for the trusted party, as well as the ability to influence their behavior. Legal arrangements play a role in providing assurance for trust in more complex social systems.

While trust is based on personal readiness and concrete proofs, law relies on impersonal motivation and is backed by physical force. As societies become more complex, the mechanisms for reducing complexity and ensuring trust become more differentiated. Trust can be formed through the interdependence of needs and the anticipation of potential sanctions. Attribution of guilt and moral judgments play a role in trust formation. Trust is often based on structural properties of shared systems, reducing the need for complete information.

Personal trust is established in social interactions. Trust is important in creating connections and generalizations within chaotic environments. Trust is focused on human beings and their freedom of action, which is an enlargement of complexity. Trust is extended primarily to individuals who are assumed to possess ordered personalities and are expected to handle their freedom in accordance with their presented personality. Trust is related to self-presentation and the symbolic implications of actions. Trust is a generalized expectation that individuals will act in accordance with their presented personality. The process of building trust involves selective presentation of self and the establishment of norms based on this presentation. Behavior communicates information about an individual's personality and trust can be formed through incremental steps. Trust-building is discussed in the context of various situations, such as personal relationships, work environments, and even illegal activities. Trust can only be offered and accepted, not demanded.

Supererogatory performance is a way to generate claims that can become the object of norms and contribute to the maintenance of trust. The process of building trust involves a series of tests and interactions, involving both small-scale activities and more significant actions, which gradually deepen trust.

Trust is complex and multifaceted, influenced by factors such as the level of risk, the need for personal orientation, and the complexity of modern social orders. The need for personal trust remains strong in various areas of social life, but there are also other ways of building trust that do not solely rely on personal interactions.

In simple societies, trust was based on religious and mythological beliefs. In more complex societies, trust relies on generalized media of communication like money, truth, and power. Money serves as a transferable form of freedom, while truth acts as a means to reduce intersubjective complexity. Trust in money emerges from the stability of its value and the ability to exchange it for goods. Trust in truth is built on the shared understanding of meaning, allowing agreement and reducing complexity. As societies become more complex, trust becomes more individualized and is tied to various forms of communication and symbolic systems.

As trust has evolved from personal relationships to generalized media of communication like money, truth, and power, these media serve as means to reduce complexity, and trust in them is crucial for their effective functioning. Trust in money relies on stability and exchange, while trust in truth is based on shared meaning. Trust in political power involves centralized reduction of complexity.

System trust differs from personal trust, is latent, and doesn't rely on familiarity but rather on explicit processes. Control over system trust is challenging and has implications for individual adjustment in a complex society.

For individuals and systems to earn trust, simply conforming to expectations is not sufficient; instead, trust is built through transformative responses that exceed expectations. Trust involves presenting oneself as trustworthy and engaging in self-presentation that reflects an interest in trust. This mutual commitment to trust creates a form of social control within relationships. Trust functions as a form of social capital that requires continuous upkeep. Trust educates and consolidates relationships, reducing complexity and allowing for more meaningful interactions. The consolidation of trust provides an advantageous way to address the fundamental challenge of social order.

Reflexivity refers to applying a mechanism to itself, intensifying its effect. The elementary forms of social mechanisms, like cognition, learning, norm-setting, and trust, become inadequate for complex social systems. Reflexivity enhances these mechanisms and adapts the social system to itself, making it challenging to revert to a simpler state. Reflexivity extends to personal trust, where individuals trust their own trust or others' trust in them, and to system trust, where trust is placed in the trust of others. While personal trust's reflexivity is often latent, system trust is based on trust in others' trust and reveals itself through sociological analysis. This understanding helps alleviate latent insecurity tied to relying on mechanisms not fully comprehended. Reflexivity enhances the potential for complexity in society, making it more adaptable and durable.

Distrust is not merely the opposite of trust; it serves as a functional equivalent for trust. While trust simplifies social complexity by taking risks, distrust can also simplify by employing strategies such as combat, mobilizing reserves, or renunciation. Distrust is characterized by a tendency to reinforce itself through interactions, leading to a self-fulfilling prophecy where distrustful behavior begets further distrust. Familiarity is a crucial factor in balancing trust and distrust, and both attitudes are subject to thresholds in experience. These thresholds simplify decision-making by introducing abrupt shifts from one attitude to another. Distrust can arise from familiarity and inconsistencies, and its articulation is influenced by past history and emotional tone. Trust and distrust are symbolically transmitted and generalized attitudes, controlled by subjective processes of simplification and reduction of complexity.

History and context are important in understanding the shifts between trust and distrust. While detailed knowledge is lacking, there is a hypothesis that social systems with necessary distrust mechanisms require strategies to prevent distrust from becoming destructive. These strategies include forms of presentation, explanations, punishment, penance, and pardon, which shift the threshold of effective distrust and reduce minor occasions for its development. Such arrangements allow social systems to gain time and accumulate trust capital, aiding their survival in critical situations.

How must a system be organized internally to be capable of conferring trust? Trust is connected to inner self-assurance; people and social systems are more willing to trust when possessing inner security. While cognitive trust is based on justification, creative trust is unjustified yet justifying itself. Trust involves a suspension of contradictions in expectation. Trust is linked to emotional attachment and assurance in self-presentation as foundations for trust. Emotional attachment stabilizes feelings towards specific objects or people, while assurance in self-presentation relies on consistent self-presentation and symbolic representation. Readiness to trust depends on the structure of the system conferring trust. Multiple mechanisms contribute to trust formation and stabilization.

Ethics cannot definitively determine whether trust is rational, and it varies depending on situations. Trust is a mechanism to navigate complexity, allowing for action beyond immediate assurance. Trust is system-rational when it helps a system cope with complexity, providing time and stability for more complex actions. Trust and distrust coexist and are dependent on each other. The differentiation between internal and external processes, as well as specific aspects of trust and distrust, can be rationalized through system boundaries and organization. Trust is essential for reducing social complexity and creating a structured representation of the world within complex societies.