to form models of the other’s models. We compare our model with the other’s model. Are our models congruent? Do we agree? And then, do we agree that we agree? If so, we have reached “an agreement over an understanding.” We have a basis for trust, collaboration, and action [ 7].

[ 7] Pangaro, P. conversations with the author, Mountain View, 1999.

Models in Design

As designers increasingly focus on systems and communities of systems, we need to improve our modeling skills. Without modeling, system design is not possible. Often service systems and computer-based applications are partly hidden or invisible, or they stretch across time and space and cannot be seen all at once or from a single vantage point. In such cases, models must stand in for systems during analysis, design, and even operation.

Using models, designers can unify otherwise
separate artifacts and actions. Interaction models

unify interface widgets. Service models unify customer touch points. Brand models unify messages. Platform models unify individual products.

Drawing has long been an essential skill for designers and the heart of design education. Bill Buxton, Dick Powell, and others assert that “ drawing is the essence of design” [ 8]. Are they correct? Perhaps—if designers focus on objects. But when attention turns to systems, modeling becomes the essence of design. Design education and practice must adapt to this changing reality.

Von Bertalanffy wrote, “The advantages and dangers of models are well known. The advantage is in the fact that this is the way to create a theory— i.e., the model permits deductions from premises, explanation, and prediction, with often unexpected results. The danger is oversimplification: to make it conceptually controllable, we have to reduce reality to a conceptual skeleton—the question remaining

[ 8] Buxton, B. Sketching User Experiences. San Francisco: Morgan Kaufmann Publishers, 2007.

Do we seem to agree, that we agree?

my model of the correspondence
of your model of the subject
to my model of the subject
(Do we seem to agree?)

my model of your model of the subject

my model of the subject

your model of the subject

May + June 2009

me

you

subject