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The Advanced Cat-Thread Theory of System Design

Posted July 2, 2016

Two people each sit atop a pole which is stabilized by wires that run from the top of the pole down to the ground. Each person holds the end of a length of thread. From the center of that thread hangs another thread with a tennis ball at the end. Nearby, there’s a cat just hanging out, watching all this transpire.

The job of these two people is to keep that tennis ball steady. They each do their best to balance on their poles, which are also slightly unsteady. Each person’s small corrective movements and adjustments help stabilize the tennis ball, but when they’re not in sync, the efforts to stabilize can actually introduce inadvertent instability. All they can do is continually re-adjust to counter all this.

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But there’s that dang cat down there, and it just can’t resist batting the ball around. The cat is arbitrary interference. The tennis ball’s stability is completely smacked away, and the two people in charge of keeping the ball steady have to do whatever they can to bring it back to a more stable state.




More people sitting atop poles are added. The two-person team now becomes what we’ll consider an organization of people. Each member of the organization has a thread which connects to the center where the tennis ball hangs. As independent operators in this group, each person has the freedom to do what they think is best to help stabilize the ball.

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This can lead to a lot of communication between each member of the organization. If we imagine that 16 people each have their own thread, and each person has the potential to communicate their intentions back and forth with the others, this opens up 240 possible communication channels.

As communication between all of the people trying to use their thread to steady the tennis ball increases, everyone’s combined actions can propagate more instability in positive feedback loops–instability triggers the instinct of each person to exercise their freedom to correct the instability. As the number of communication channels are too much to ever manage, people have to focus on not only correcting the tennis ball’s instability, but also compensate for the unintentional introduction of instability through the uncoordinated movements of everyone else.

And still down at the bottom, we have the cat, batting away, ruining our efforts. Something must be done.




We have 16 people trying to control the tennis ball. And one pesky cat. Each person is busy exercising their freedom and best judgement to both balance themselves and use their threads to stabilize the tennis ball. Maybe what we need isn’t more freedom, but less.

We have two common ways to reduce the instability of the organization.

Option 1: We add a boss that can sit on a taller pole with threads connecting down to the people beneath, and the boss can exercise their freedom to try and stabilize their subordinates. The boss can help keep them steady, and they can then focus more on keeping the tennis ball steady.

Option 2: Rigid connector threads can be added between each of the subordinate’s threads, a set of rules that are designed to limit the amount of instability each person can introduce by constraining the potential movement through the web-like structure. This also helps distribute the inadvertent instability of each thread across the whole system.

This still doesn’t address the cat; the arbitrary interference. We need a third option…

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Option 3: Someone shoots the cat. The organization no longer accepts arbitrary interference, it is directly dealt with outside of the system.

The boss and the rules are stabilizing the freedom and arbitrary movement of the people. The people on the poles are now both free enough, and constrained enough, to effectively manage stabilizing the ball. And the cat–arbitrary interference–has finally been eliminated… at least until another cat comes along.



This is my interpretation and retelling of an excerpt from a series of radio broadcasts with Stafford Beer in 1973, which was subsequently turned into a paper called “Designing Freedom”. I want to qualify this article by saying I am far from any sort of expert on these concepts.

Stafford Beer was a communication and systems theorist, and one of the preeminent cyberneticist* of the mid-late 20th century. As a designer who has a deep interest in systems as part of my passion for service design, his work (and cybernetics* in general) is very inspiring and the spiritual ancestor to what I believe is the core of service design thinking and doing.

This article has been in my drafts folder for about 5 years. My mind always wanders back to this metaphor when practicing and contemplating service and system design. “Cat-threads” has become a codeword between me and a few like minded individuals to represent the nuance, frustrations, inefficiencies and realities of maintaining systems of any kind.

Expand your mind and read the paper. The story comes from page 7 of the 44 page transcript. I left out a few important concepts in order to streamline the metaphor, but it doesn’t impact the basic idea.

It is a fascinating, enlightening, and stimulating journey into systems thinking from a (largely) pre-digital era.

Or, at the very least, take a look around and see if you can observe where the poles, threads, connectors, overseers, tennis balls, and cats reside all around you.

Page 7:

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Page 7 from “Designing Freedom” by Stafford Beer, The Massey Lectures, Canadian Broadcasting Corporation



… a transdisciplinary approach for exploring regulatory systems, their structures, constraints, and possibilities.

–has come to be associated in colloquial language with “cyborgs”; robotic arms and laser eyes and the Terminator. In reality, it has a deep history in systems thinking and communication theory. Give it a glance.

Sources: Designing Freedom “The text of six radio broadcasts given in the autumn of 1973 as the thirteenth series of Massey Lectures which were established in 1961 by the Canadian Broadcasting Corporation to enable distinguished authorities in fields of general interest and importance to present the results of original study or research.” 

Artwork from “Designing Freedom”, artist unknown.

I love all things experience design. I work as a Principal Service Experience Designer at Intuit in Mountain View, CA.

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