Brenda Zimmerman and Sholom Glouberman have proposed a distinction among three different kinds of problems in the world: the simple, the complicated, and the complex.
Simple problems, they note, are ones like baking a cake from a mix. There is a recipe. Sometimes there are a few basic techniques to learn. But once these are mastered, following the recipe brings a high likelihood of success.
Complicated problems are ones like sending a rocket to the moon. They can sometimes be broken down into a series of simple problems. But there is no straightforward recipe. Success frequently requires multiple people, often multiple teams, and specialized expertise. Unanticipated difficulties are frequent. Timing and coordination become serious 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, Zimmerman and Glouberman 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.
Yet we all know that it is possible to raise a child well.
It’s complex, that’s all.
The Checklist Manifesto: How to Get Things Right (find in a library)