Open peer commentary on the article “Radical Constructivism and Radical Constructedness: Luhmann’s Sociology of Semantics, Organizations, and Self-Organization” by Loet Leydesdorff. > Upshot: Leydesdorff emphasises the uncertainties involved in the communication of meaning. Luhmann posited three types of media, each of which reduces one type of communicative improbability. The theory of cultural evolution supports Leydesdorff’s emphasis on the uncertainty of communication, and agrees that different media are needed for communication within and across social boundaries. But it highlights the distinction between (...) media and the symbolic codes that give them structure; and it raises the question whether Luhmann’s symbolically generalized communication media are really media at all. (shrink)