The question whether social systems should be understood as autonomous phenomena or only as a result of the actions of (rational) actors is an everlasting object of controversy. This contribution discusses the suitability of the concepts of autopoiesis and interpenetration in Luhmann's theory of social systems for constructing a convincing theory of the relation between actor and system. The conclusion is that Luhmann's concepts are insufficient for an explanation of the selfproduction of social systems in terms of communication alone. Other concepts are needed, which point at the partial inclusion of psychic and organic systems in the communications constituting social systems, and which at the same time respect the principle of autonomy and self-production of these systems. Communication now appears as a new (emergent) unity of operations of at least two human beings. Not only human beings, but also social systems can be said to be able to observe.