Essays & Articles


The “science” in the science of design

My Foreward for R. Batra, C. M. Seifert, & D. Brei (Eds.), The psychology of design: creating consumer appeal. New York: Routledge.

Norman, D. (2015). The “science” in the science of design. In R. Batra, C. M. Seifert, & D. Brei (Eds.), The psychology of design: creating consumer appeal. New York: Routledge.

Designers create practical goods and services. This is what makes design so special, so very different than most academic disciplines that do in-depth studies of the topic of interest. Design is a wonderful field because it actually creates things that change people’s lives. This is all very nice, but the question before us is whether there is a science to this behavior or whether it depends upon the whims, insights, and creativity of talented designers.

Today, much of design is done through the intuition, instincts, and insights of the designers, honed by years of practice, training, and mentoring.  Some parts of design, especially interaction and visual appearance, have considerable basis in the cognitive sciences of interaction and perception. Other parts lack a solid base of evidence. Can design be a science? Many in the design community think the answer is no. I find this misguided.

In a recent posting to a mailing list that discusses such problems I classified the different types of rigor possible in a field like design. Here is what I said (edited slightly):

Can design be a science, driven by theory? Or can we at least enhance the quality of our methods through evidence-based design, where practices are studied, evaluated, and then codified with statements about their efficacy and the conditions where they are appropriate.  Or should design remain as it is today, based upon the skills and talents of designers?   My answer? All three.I strongly prefer design theory as a way to proceed: theory supported by evidence.Most areas of design today do not have appropriate theories — indeed, it may be impossible to develop appropriate theories — and in these cases I strongly argue for evidence-based design as the way to proceed.Many areas of design today do not have a base in evidence — indeed, it may be impossible to develop appropriate evidence — and in these cases we rely on the skills and insights of skilled designers as the way to proceed.

In the history of science, this is a common path. First come observations. Then comes classification. Then simple measurements of some components. With time, a theoretical basis develops. The scientific method is a procedure for probing, testing, disputing and eventually converging upon useful, tested theory. Not all science or engineering practice today is theory based. Some is still evidence-based. Medicine is a good example of a field with a mixture of deep theory, a non-theoretical component based upon evidence, and numerous components not well supported by either evidence nor theory.

Design is following these paths, but in its own way, for each field has different goals, methods, and techniques. In many disciplines the problems to be tackled are well defined. In design, the activities and issues that we address are so vast that I believe that most of design will fall into my categories 2 and 3: no appropriate theory, but a combination of evidence-based best-practices and the skills and insights of designers.

Design is a complex field. Some components of design already are based upon good science, usually from the behavioral and cognitive sciences. Some are at the pre-scientific level of understanding. I believe that with a proper attitude toward evidence-based studies, these areas can also become either scientific, or at least rigorously proven to be effective when used under well-understood circumstances. Some aspects of design seem primarily based upon human creativity, sense of style, and other socially mediated conventions. These may never be scientific, but they do play a critically important role in the quality and acceptance of design.

So, can design be a science? Sometimes yes, sometimes no. Can it be empirically based, evidence driven? Yes. Will it have to reply on intuition and the creativity of individual designers? Sometimes, yes.

The power of design lies with its methods. In modern design, the process starts with observation of the people for whom the design is intended, spending time observing, studying, and developing a deep appreciation for the underlying issues. I have a rule when I’m asked to consult: “Do not solve the problem I am asked to solve.” Strange rule: why do I have it? Because the problem given to us is seldom the fundamental, root problem – it is usually the surface problem or the symptom. Design is powerful because we do not just solve problems: we define them. We spend a lot of time trying to understand the fundamental issues that should be worked on, not the superficial issues that are easily observed.

Many of the important problems in the world cannot be solved, either because not enough is known or because they are fundamentally unsolvable: there are too many factors, too many competing constraints, too many issues that are fundamentally incompatible. “Wicked” is the term applied to these problems by both economists and designers: wicked problems. Design differs from most disciplines in that it is not searching for truth. It is searching for “good enough,” or sometimes, simply for “better.” In the words of Herbert Simon, we satisfice. Design has to create real value, it has to make a difference. It has to look for large effects, not small ones, things that make a significant difference, whether or not they are optimal or perfect.  Design is the field of practical accomplishment, where the results are continuously studied, modified, and improved. Big effects, not small ones. Significance in people’s lives, not the tiny difference of statistical significance.

Designers think by drawing and by making. Not with words, not with equations, but by drawing, sketching, and building. It’s a different kind of thinking. Drawing and sketching are powerful because they readily allow two, three, or even four dimensions to be represented. Space and time, both.

Part of design is a form of applied art. Yes, we want things that work well, but we also want them to be attractive, to give pleasure: nice to look at and that feel good in their operation. That’s an art form, and we still don’t quite know how it happens. Many parts of the design process remain art rather than science.

Let me give you an example. On today’s smart phones and modern operating systems, when scrolling through a list by gesture, when the finger is lifted off the screen or track pad, the list keeps scrolling, slowing gently. It has a virtual “momentum” and “viscous friction” so that it slows non-linearly. At the end of the list, what does it do? It bounces! What is the function of the bounce? None whatsoever, except that it makes us happy. That’s what great designers put into products: pleasure, feeling good, making us happy.

What is the science behind the addition of the tiny little pleasures these products provide? We don’t know. Maybe we’ll never know. I don’t have an answer for what kind of theory might ever develop in the artistic, pleasurable, fun, and emotional component of design, even though these are crucial aspects of successful design.

This essay has been about the traditional area of design. Many of the chapters of this book come from the field called “consumer psychology,” which include lots of insights and evidence about people’s preferences, the importance of sensory look and feel, the impact of color, and how price affects adoption. These issues overlap the concerns of the traditional product designer, but should be a fundamental part of the design process, considered during the early phases of design.

Design is a multi-faceted, complex enterprise.  It involves the initial choice of what to make, a deep understanding of people, of materials, and of technology. It requires understanding how people decide upon purchase, and then use products. It covers an extremely wide range of activities and different disciplines of study and training. It is this depth and richness that makes design such a wonderful, fascinating field.