Systems thinking has a long history. Its influence on design can be traced back for many decades. However, systems thinking remains almost unknown today among practicing designers and design researchers. Systems thinking is relevant, especially in light of all that is going on in modern society.
When designers work, they commonly create two models in their practice: a model of the current state, describing the situation to be improved, and a model of the idealized future state that a design solution will address. While these models are useful, they can remain high-level abstractions, failing to document a system in detail. Understanding how systems are organized and analyzed and applying this understanding in moving from an abstract model to create a design solution are invaluable skills for designers.
The concept of a system is easy enough to comprehend, but understanding a whole system can be difficult. More often than not, we can grasp only a few parts instead of getting the whole structure. Understanding systems can help any designer, or anyone collaborating with a designer, to understand the context around a problem and how to create an actionable solution.
Systems are identifiable everywhere in nature and the developed world. As a young child, you probably learned about the solar systema group of planets that rotate around the sun. If you have received medical care recently, you most likely interacted with the healthcare system. A local neighborhood group may be working to save the ecosystem in your community.
The solar system, the healthcare system, the local ecosystem, neighborhoods, church groups, organizations, cities, and societies are all examples of systems.
A system in its most basic definition is a whole, acting as a unit of interacting parts. A system has interrelated elements whose relationships are both structural and functional. Structurally, a system is made up of subsystems that also contain subsystems themselves. Each system also relates to greater systems in the universe. Functionally, every part of a system depends on other parts of the system for something. If part of a system changes, another part of the system will likely also change as a result. The emergent properties of a system are greater than the parts of the system themselves. A system maintains a relationship with everything within itself and with larger and greater systems.
As a basic example of a system, consider a miraculous one: the human body. The respiratory system works in tandem with the circulatory system, the muscular system, and the nervous system. Products can also be collected and used as a system. Products can be used to extend the capabilities of the human body. An athlete or camper has a system of products that she relies on for an event or excursion. We use a system of products, including cars, bicycles, public transportation, shoes, coats, canes, and walkers, to get around. A service can be considered a set of products, or touchpoints, that collectively offer a transaction or experience to a customer. The products within a system can be intangible or tangible things.
Anyone who engages in the design processusing human power to conceive, plan, and realize products that serve human beings in individual or collective goals engages in a systems approach. Consider the following examples.
A simple use of a system for a visual design is considered in this example. A graphic designer is tasked with designing the layout for a book. After creating a number of hand sketches to ascertain the overall feeling of pages and chapters, she is ready to give form to the design. She will first establish a set of repeating measures, or modular units, upon which to base the design. She will take an inventory of the text and visual elements needed to communicate the design, choose a type family or two to work with, and find suitable designs for each of the elements. Working guidelines for the design of each of the elements will be created. Excerpts of text will be tested with all of the element designs for legibility and aesthetic balance. Finally, single pages and double-page spreads will be subjected to what designers call "the squint test"assuring the design looks good holistically, with balanced visual contrast.
A system in its most basic definition is a whole, acting as a unit of interacting parts. A system has interrelated elements whose relationships are both structural and functional. Structurally, a system is made up of subsystems that also contain subsystems themselves.
A more complicated example of how a systems approach can be used in the design process is in seeking a solution to problems that are complex, unique, and not reducible to smaller sub-problems. These types of problems are called "wicked problems," a term coined by Horst Rittel . As an example of using a systems approach to derive a solution to a wicked problem, consider the problem of supplying fresh drinking water to people around the world.
There are many large aspects to this problem, including the basic human right of access to clean drinking water; the realities, demands, and resources of supplying water all over the world; the cultural differences in how we consume water; and the laws, regulations, and public policies around water supply. There are many small aspects to this problem, including how water is bottled and supplied; the design of the bottle; the material that is used to create the bottle; the disposal and reuse of the bottling material; and the functional, symbolic, and even aesthetic aspects of the bottles themselves. Deciding which aspects of a wicked problem should be focused on is done through human judgment. The bias that one brings to deriving a solution to a wicked problem can be deemed good by some and bad by others.
Consider bottled water as a means to a solution. Certainly, for some, it is a reliable, more accessible form of drinking water. In many places around the world, it is a safer source of drinking water than tap water. Statistics show that bottled-water consumption has grown exponentially in the past decade or two. But in some places, it has also become a lifestyle producta symbol of comfort, wealth, and discretionary income.
The material from which water bottles are made, polyethelene terephthlate, or PET, is produced from fossil fuels but is recyclable. However, much of the packaging from bottled water ends up as waste in landfills. As bottles settle and degrade, CO2 is generated as a by-product, creating tons of CO2 emissions.
Clearly, one of the issues in producing bottled water is the strain it places on our ecosystems. In response, many solutions have been considered. For example, the design of PET water bottles has been modified to use less material, decreasing steadily over the past five years. In addition, product designers are considering new materials and making bottles that are not disposable and not harmful to the environment. Nalgene and Sigg bottles are two non-disposable product lines that have gained popularity in the U.S. These products force consumers to think about whether or not using PET bottled water is really more convenient, safe, or environmentally beneficial than carrying fresh drinking water in an alternate container. In addition, the symbolic appeal once associated with "spa"-brand drinking water is being replaced by the symbolic appeal of carrying an Earth-friendly container. However, while these design solutions achieve the goal of producing fewer PET bottles and reducing the sale of bottled water, they do little to address larger issues around clean drinking water, including the public policies around water testing, water consumption, and water control.
So, in focusing on a solution to this problem, a designer or design team could create many interventions, ranging from a better PET bottle to a biodegradable bottle to a durable, Earth-friendly bottle, or even new policies and practices around this diminishing resource. Many framings of this problem are possible. A designer or design team can use a systems approach to shape design judgment in creating a solution to this kind of wicked problem.
Horst Rittel, a mathematician, architect, and designer, extensively studied and compared rational and creative approaches to problem solving over a variety of disciplines . Rittel differentiated problem types as either tame or wicked. Tame problems have trivial concerns; are quickly identified; and are solved rationally, practically, and efficiently using linear problem-solving methods. On the other hand, wicked problems do not lend themselves to simple characterizations or to simple procedures for solution. According to Rittel, wicked problems are a "class of social system problems which are ill-formulated, where the information is confusing, where many [shareholders] have conflicting values, and where the ramifications in the whole system are thoroughly confusing" .
One issue is the way in which Rittel's characterization leads to what Nelson calls "assessment paralysis"there is no simple or direct way to go forward . However, using a systems approach, a wicked problem can be reframed from an irreducible situation to a design situation.
One of the conceptualizations of systems thinking that halted assessment paralysis was in the work of C. West Churchman, who stated that a person could be a component in a system. From there, a strategy for social systems assessments was created by Churchman's student, Harold Nelson; it combined a multitude of systems models, theories, approaches, and methods into an actionable framework (see Figure).
Nelson's process has five stages, but the stages are neither linear or crisply delineated. However, the process contains identifiable transitions. In the first stage, designers synthesize a systemgetting a holistic grasp of the system and using their judgment to frame the problem. In the second stage, designers analyze the systemunderstanding details and interconnections between components and making lists of attributes. In the third stage, designers critique the systemidentifying problems with the current state. In the fourth stage, designers intervenemaking explicit the proposed solutions. In the fifth stage, designers redesign the systemimplementing their vision of an improved future state.
Using Nelson's framework, we can see how a systems approach can provide a resource for designers to rely on their judgment in framing and solving problems and looking at a problem in a rigorous way. This approach is relevant today, because design is moving into new and more complex areas, including the design of the intangible, such as service design and public policy. Conventions for how to deal with these problems are largely absent from design research and practice today. For this reason, the design community should revisit systems thinking. Systems are everywhere; systems approaches should be everywhere, too!
Jodi Forlizzi is an associate professor in the Human-Computer Interaction Institute and School of Design at Carnegie Mellon University in Pittsburgh. Her research interests center on notification systems ranging from peripheral displays to robots.
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