Illustrated by Francesco Ciccolella

Thinking Inside the Square

How sticky notes can boost your design thinking process.

If you’ve worked as a designer or with designers, you know how many sticky notes they go through. Chances are, you’ve seen a wall or whiteboard papered over with countless square, adhesive-backed notes too many times to count. Maybe a nearby pad of sticky notes has helped you capture a faint new idea before it darted away.

Why are sticky notes used so commonly in the design process? And why is it important to think about sticky notes and other simple tools? Understanding how designers use sticky notes to hone ideas can provide insight into design thinking itself.

Reasoning is typically divided into two types: Deductive reasoning starts with a general rule and moves to a specific conclusion. It’s used in formal logic and mathematics. Inductive reasoning builds general hypotheses out of specific observations. (Scientific research often uses induction). A growing body of research identifies design thinking as belonging to a third type of reasoning: “abductive reasoning.”

Based on scattered information and faint intuitions, abductive reasoning makes guesses about what might be a likely explanation or solution. The philosopher C.S. Pierce, who first described abductive reasoning, wrote that “abduction is the only logical operation which introduces any new ideas.” In other words, abduction is how we think of new notions before induction or deduction have enough information to work.

What does all this have to do with sticky notes? While new ideas are generated abductively, these ideas must then be documented, communicated to others, connected to other ideas, and refined.

A recent article in Design Studies looked at how sticky notes help designers create and refine new ideas. Its authors noted that shared thinking tasks are distributed among members of a group. Design teams had to “externalise” each member’s internal ideas to coordinate thinking with others. Sticky notes are one such method of externalisation.

Sticky notes have many qualities that make them good tools for externalization. They’re cheap, so they can be used and discarded without much cost (psychological or actual). They are small and consistent in shape, making them perfect for holding a single discrete thought. And their reusable adhesive backing means they can be repositioned to show connections between different ideas.

Going deeper, the article’s authors cite previous research that identified 4 different levels of externalisations:

  1. Informational externalisations share an idea with another person. This level happens every time you write your idea on a note and paste it to a shared space.
  2. Formational externalisations help bring an idea into being. For example, writing on a note triggers new ideas that are then written on other notes.
  3. Transformational externalisations occur when designers collaboratively generate ideas and modify one another’s notes.
  4. Transcendental externalisation happens when designers reach a point of being able to think about thinking. They’re able to easily understand and modify the relationship between different ‘kinds’ of ideas. As the paper puts it, they can “work with the material of ideas much as one might arrange images for a collage, or build with lego.”

Research found that the design teams used sticky notes on all 4 levels, often overlapping level use to support their creative thinking and abductive reasoning. Sticky notes helped designers see their thinking process from a critical, outside perspective and overcome the intimidation of a blank wall.

What’s the takeaway here? First, paying attention to simple tools gives us deeper understanding of how tools shape our design process. We end up with more detailed knowledge of how we think, create, and work. Understanding design thinking on a fine-grained level can help us explain why our process is good, or how it could be better.

Finally, here’s what other designers have to say about the humble sticky note. Matt Cooper-Wright at IDEO asks, “you might wonder if you really need advice on how to use a post it note,” and offers practical tips for their use: putting a definition or explanation on each note prevents you from forgetting what a note means later; using different coloured notes for different categories helps you quickly determine patterns; a fat pen keeps notes from getting too wordy.

Davis Levine’s post in a similar vein reveals a right and a wrong way to remove notes from the pad (really). Meanwhile, Jonathan Courtney has developed a novel method for using sticky notes to rapidly test ideas and come to consensus, mixing open-ended abductive guessing with quick rounds of feedback and evaluation.

We’re experimenting with content that is exciting and relevant to designers and those who collaborate with them. If you have thoughts on the perfect way to use sticky notes or design-related article ideas for what you’d like to read, give us a follow at, connect with us on LinkedIn, or reach out at

Further reading:

· “Grouping notes through nodes: The functions of Post-It notes in design team cognition” by Graham Dove et al., in Design Studies 57: Designing in the Wild.

· “The core of ‘design thinking’ and its application” by Kees Dorst, in Design Studies 32, Issue 6 (2011).

· “Externalisation and design” by Alan Dix and Layda Gongora (2011).

· Lilian Ayla Ersoy on how design thinking can go wrong