The basics, dynamics and speeches of the various ways of knowing, creating and solving cannot be the same in all disciplines or have unique parameters for traditional sciences. Although there might be a match in purposes, methods, ends or other characteristics, its diverse nature is increasingly evident. Design consolidates its theory by proposing various approaches that enrich its understanding and exercise, which, in turn, makes it difficult to specify its singularities. Multiversity of design is not a weakness but its greatest strength as a way of thinking-solving human interaction and with its environment. The claim on ambiguity and the rhetoric about design that distort its epistemology reveals multiple and hidden paradoxes from classic visions of knowledge. This article reflects and proposes on the theoretical aspects of design, understood as specialized thought that applies, evaluates and develops new knowledge. As a conceptual exercise from the professional and academic fields, it is based on the analysis of a widespread case of literature, criticizing the rhetoric gaze of design by Buchanan in the article analyzed. By making its categories, criteria and roles visible, we propose design as a rational exercise, not merely subjective, autonomous, but supported and collaborative with other disciplines whose contributions it integrates via the language of form from, by and in its own constructs and conceptual strategies, which allow solving the initial need from which any project arises.