Luhmann argues that social systems are primarily concerned with facilitating communication and interaction among their members. This is because communication is the primary means by which social systems coordinate their activities and adapt to their environment.

Luhmann argues that the basic unit of analysis in sociology is the social system, not the individual or the social group. This is because social systems are the primary units of social organization and action.

Luhmann distinguishes between open and closed social systems. Open systems are those that are able to exchange information and energy with their environment, while closed systems are those that are not. Open systems are more complex and adaptive than closed systems.

Autopoiesis is the ability of a social system to reproduce itself. This means that social systems are able to create and maintain their own boundaries, and to generate new elements that are similar to the existing elements.

Structural coupling is the way in which social systems interact with each other. This interaction is mediated by shared symbols and meanings, and it allows social systems to coordinate their activities and adapt to their environment.

Double contingency is the way in which social systems interact with each other. This interaction is mediated by shared symbols and meanings, and it allows social systems to coordinate their activities and adapt to their environment.

Social differentiation is the process by which social systems become more complex. This process involves the development of new social roles, institutions, and organizations.

Functional differentiation is the process by which social systems become more complex. This process involves the development of new social roles, institutions, and organizations.

System closure is the ability of a social system to reproduce itself. This means that social systems are able to create and maintain their own boundaries, and to generate new elements that are similar to the existing elements.

Emergence is the process by which new social systems are created. This process involves the interaction of multiple social systems, and it can lead to the development of new social structures and institutions.

Self-organization is the process by which social systems learn and adapt. This process involves the interaction of multiple social systems, and it can lead to the development of new social structures and institutions.

Social evolution is the process by which social systems become more complex. This process involves the development of new social roles, institutions, and organizations.

Social change is the process by which social systems become more complex. This process involves the development of new social roles, institutions, and organizations.

Social order is the way in which social systems maintain their stability. This involves the development of social norms and institutions that regulate the behavior of individuals and groups.

Social control is the way in which social systems maintain their stability. This involves the development of social norms and institutions that regulate the behavior of individuals and groups.