The principal thesis of this book is that the key element of design is representation. If we were to consult a standard dictionary, we would find representation defined as “the likeness, or image, or account of, or performance of, or production of an artifact.” Note, however, that whereas our dictionary defines representation as a noun in which terms such as image and likeness refer to the artifact being designed, it also suggests aspects of a verb when it defines the design process in terms of a performance or a production. This suggests that representation in design incorporates both representation of the artifact being designed as well as representation of the process by which the design is completed. We now examine briefly both types of representation.

Representation of Artifacts for Design

Suppose we are charged with the design of a safe ladder. What does it mean, first of all, for a ladder to be “safe”? That it should not tip on level ground? That it should not tip on a mild slope? What is a mild slope? How much weight should a safe ladder support? Of what material should it be made? How should the steps be attached to the frame? Should the ladder be portable? What color should it be? How much should it cost? Is there a market for this ladder?