The public is a creation of the mass media system.
The mass media system, which began with the invention of the printing press, has one function: to distinguish between new information and what is already known (or non-information). In this way, the mass media tells the public what to pay attention to (or what they should know) and what to ignore or forget. When the mass media marks something as information, it publishes it–or it marks it by publishing it. The mass media thus creates a reality, but this is not an objective reality or even society’s single reality; it is the mass media system’s reality. Thus Luhmann’s book on this subject is titled The Reality of Mass Media.
As discussed previously, Luhmannian systems theory, inspired by George Spencer-Brown’s Laws of Form (1969), begins with the injunction to draw a distinction, and these distinctions, while appearing binary, are three-fold: the marked side, the unmarked side, and the distinction itself, permitting oscillation between the sides.
The mass media system slices its reality into information and non-information—and that’s all that counts for the mass media. The mass media system must continually produce news because the moment information becomes known it loses its status or value as information; it becomes non-information and must be replaced by new information. As Luhmann puts it,
New information is continually needed to satisfy the mass media system” because the moment information is actualized, or becomes known to the public, it loses its informative values and becomes non-information (Introduction to Systems Theory, p.121).
The public belongs to the mass media system because it closes the communication loop. In fact, the public is a creation of the mass media system, beginning with the invention of the printing press. Prior to the invention of the printing press there was no public as such.