Sadowski's book offers a comprehensive model of communication based on deductive formulations of systems theory supported by evolutionary thinking. The systems model generates the following types of communication: direct, or contiguous communication, and indirect communication, involving displaced reference, exemplified by indexical, iconic, and symbolic communication. Indexes are physical changes created by a communicator in the environment (e.g. a shadow, a footprint, or a photograph). Iconic communication in turn is based on perceived similarity between sign and referent - a cognitive disposition reflected in art as well as in human tendency to interpret the world in terms of analogies and correspondences. Finally symbols, with their arbitrary connection between sign and referent, underlie the unique communicative phenomenon of human syntactic speech. The distinguished types of communication appear to correspond with the evolutionary sequence of interactions between inanimate.