This paper discusses a basic methodological and philosophical confusion in the study of human communication. Various scholars have assumed that the study, description, and definition of various systems have led to an understanding of the processes which underlie, or generate, human communication behavior. In effect, two levels of analysis and study are proposed: level one, which allows for the development of an unlimited number of systems and their description in the observable environment of human beings, and level two, which is a set of fundamental communication rules innate in human beings. If we consider the differences between these generative mechanisms, or rules, we will take a major step toward the development of a variety of methodologies to empirically identify human communicative activity on both levels, without confusing the two. (Author/AA)