Sketching and the Psychology of Design

following considerations are suggested by an excellent essay of Gabriela Goldschmidt, The Dialectics of Sketching (1991), for whose publication anybody interested in visual design should be most grateful. author, an Israeli architect, undertakes to answer question, What kind of reasoning does sketching represent? question arises because sketching does not consist simply of representing on paper images held in designer's mind; it consists rather in a dialectic process, the oscillation of arguments which brings about gradual transformation of images ending when designer judges that sufficient coherence has been achieved.' This most relevant question points to psychological issues that aroused my interest. It reminded me of one of classics on subject of visual perception, Ernst Mach's treatise Analysis of Sensations, first published in 1886.2 Mach, a physicist, realized that scientists have no other access to material world than what is transmitted to them by senses, particularly sense of vision. Therefore, physicist must know what exactly information generated by vision is and by what rules perception operates. physicist's vital concern with perception parallels that of architects, who are also dealing with world of physical matter. They, too, have no other access to what they want to achieve or means by which to achieve it than what their senses make available to them. In what follows, I am relying on Goldschmidt's essay and on Mach's treatise. Goldschmidt describes process of creative design as an interaction of arguments and moves. Arguments are labors of designer's mind, explorations of task and reasoning about it. Moves are physical motions engendered by arguments. Moves are what psychologists call behavioral aspects of human activity. architect's moves produce drawings and they supply essential new food for arguments. drawings are tangible visual percepts, and it is their relation to arguments that is principle concern of present discussion. Mental images derive from optical percepts, but they are not identical copies of them. Mach describes them as necessary completions and elaborations of percepts. They differ from optical 1) Gabriela Goldschmidt, The Dialectics of Sketching, Creativity Research Journal 4: 123-43. See also, Gabriela Goldschmidt, Criteria for design evaluation: a process-oriented paradigm, in Y. E. Kalay, ed., Evaluating and Predicting Design Performance (New York: Wiley, 1992). In this article I have not referred to this second paper.