The Difference Between Complicated and Complex

The book I am currently reading, The Checklist Manifesto: How to Get Things Right by Atul Gawande, references a white paper discussing the difference between complicated and complex. The white paper, entitled The Simple, the Complicated, and the Complex: Educational Reform Through the Lens of Complexity Theory, is written by Sean Snyder and is published through The Organization for Economic Cooperation and Development (OECD). It can be found here. Both sources, the book and the white paper, adapted information from the original study by Professors Brenda Zimmerman of New York University and Sholom Glouberman of the University of Toronto where they analyzed Medicare reform in their landmark paper Complicated and Complex Systems: What Would Successful Reform of Medicare Look Like?, which can be viewed here. All three sources discuss the difference between complicated and complex problems.

The following is an excerpt from the book explaining the difference between complicated and complex with an example:

Complicated problems are ones like sending a rocket to the moon. They can be sometimes broken down into a series of simple problems. But there is not a straightforward recipe. Success frequently requires multiple people, often multiple teams, and specialized expertise. Unanticipated difficulties are frequent. Timing and coordination become series concerns.

Complex problems are ones like raising a child. Once you learn how to send a rocket to the moon, you can repeat the process with other rockets and perfect it. One rocket is like another rocket. But not so with raising a child, the professors point out. Every child is unique. Although raising one child may provide experience, it does not guarantee success with the next child. Expertise is valuable but most certainly not sufficient. Indeed, the next child may require an entirely different approach from the previous one. And this brings up another feature of complex problems: their outcomes remain highly uncertain. 

Mr. Snyder elaborates on the difference between the two:

Complicated contexts are the realm of expertise and data analysis – the known unknowns. Cause and effect are not self-evident but can be teased out through analysis. The policy maker’s role here is to assemble the requisite minds and encourage differing opinions while avoiding paralysis of analysis. Once cause and effect are understood, interventions can be undertaken to tackle the problem, and, if the required expertise were present during the discussion phase, as in the case of the rocket launch above, the solution should work and be replicable.

The complex is the realm of the unknown unknowns. It is a space of constant flux and unpredictability. There are no right answers, only emergent behaviours... The policy maker’s role in this space is to create safe spaces for patterns to emerge, which is best done by increasing levels of interaction and communication within the system to its largest manageable level. Expertise is useful but not sufficient to solve complex problems – great patience and a sharp eye for new behavioural patterns are the only way forward.

Once an understanding of the difference between complicated and complex is developed, what are the practical implications when problem solving?

The key is recognition. Is the issue is complicated or complex? This will then prompt answers to other questions: Is there a pattern to be followed? Can something be replicated to achieve success? Is one dealing with dynamic characteristics? Can a formula be applied? Will outside expertise solve the problem or only increases the chances of solving the problem? Will a heuristic help?

Despite often being used as synonyms, complicated and complex are very different. It is important to understand the differences between the two and to be able to apply it to problems and decisions in order to take the steps towards resolutions more effectively.

- Joe