WTF? Let me explain using the terminology Alexander introduced in this book.

Form, Context & Forces

Alexander writes:

Every design problem begins with an effort to achieve fitness between two entities: the form and its context. The form is the solution to the problem; the context defines the problem.

Let’s say you are a designer tasked with redesigning a kettle (which is also an example that Alexander uses in the book). The kettle is the form and the environment in which it is used is the context.

Alexander uses the analogy of iron filings in a magnetic field to describe how the form is shaped by the forces in the context. Depending on the direction of the field — the context, the filings arrange themselves in a certain way-the form.

However, he also notes that things aren’t so straightforward in a real design problem, because we don’t know the ‘direction of the field’.

“What does make a design problem in real world cases is that we are trying to make a diagram for forces whose field we do not understand. We are searching for some kind of harmony between two intangibles: a form we have not yet designed and a context which we cannot properly describe.”

So, what to do?

Ensemble & Misfits

Redesigning the kettle itself is not the objective, what the designer is trying to do is enable a certain outcome in the user’s context through this form (such as being able to get a fast cuppa tea). So: it is about how well the form fits the context that determines a successful design, not the form alone. Alexander uses the word ensemble to describe this:

“When we speak of design, the real object of discussion is not the form alone, but the ensemble comprising the form and the context.”

When an ensemble is working well, Alexander describes it has having ‘good fit’.

“Good fit is a desired property of the ensemble which relates to some particular division of the ensemble into form and context. We want to satisfy the mutual demands which the two make on one another. We want to put the context and form into effortless contact or frictionless coexistence.”

But how do we tangibly know if there is a ‘good fit’? Alexander says that it is hard to see good fit, but easier to see the lack of it, or misfits.

“It is the departure from norms that stand out in our minds rather than the norm itself. Their wrongness is somehow more immediate than the rightness of less peculiar behavior, and therefore more compelling . Whenever an instance of a misfit occurs, we are able to point specifically at what fails to describe it. It seems as though in practice the concept of good fit can only be explained indirectly.”

So back to our kettle, if study the context, you need to seek misfits. You might study the ergonomics of a kettle; You might look at how effective current products are — how well, or how fast they heat water; You might even visit some homes to see in what scenarios people use a kettle and so on. A misfit might be a user needing more portability, or perhaps accidentally spill scalding hot water on themselves, or a lack of visual or aural confirmation may result in all the water just boiling away.

Dividing the Ensemble

Alright, so study the context, find misfits. But there can be an immense number of misfits. Which ones to design for? Further, when you study the context the misfits might not just be because of the kettle. Alexander recognizes this and writes:

“No one division of the ensemble into form and boundary is unique. A good designer is sensitive to the fit at several boundaries within the ensemble at once. In a perfectly coherent ensemble we should expect the two halves of every possible division to fit together. (Therefore,) we ought to design with a number of nested, overlapped form-context boundaries in mind”

This is the classic trope of innovation, that only when you look at the entire “system” can you truly reframe the problem. The Apple iPod for example, solved for misfits at multiple boundaries, such as buying digital music and ripping digital music and not just creating a new form of the mp3 player.

Similarly, a designer could decide that the kettle is the wrong way to heat water, and work on a different part of this ensemble.