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Systems: complicated and complex – Aaron Dignan

The engine inside a car is complicated. A complicated system is a causal system – meaning that it is subject to cause and effect. Although it may have many parts, they will interact with one another in highly predictable ways. Problems with complicated systems have solutions. This means that, within reason, a complicated system can be fixed with a high degree of confidence… here, experts can detect patterns and provide solutions based on established good practice…

Traffic, on the other hand, is complex. A complex system is not causal, it’s dispositional. We can make informed guesses about what it is likely to do (its disposition), but we can’t be sure. We can make predictions about the weather, but we can’t control it. Unlike complicated problems, complex problems cannot be solved, only managed. They cannot be controlled, only nudged. This is the domain of the butterfly effect, where a small change can lead to something big, and a big change can barely make a dent. Here expertise can be a disadvantage if it becomes dogma or blinds us to the inherent uncertainty present in our situation.

Complex systems are typically made up of a large number of interacting components – people, ants, brain cells, startups – that together exhibit emergent behavior without requiring a leader or central control. As a result, complex systems are more about the relationships and interactions among their components than about the components themselves. And these interactions give rise to unpredictable behavior. If a system surprises you, or has the potential to surprise you, it is likely complex. Software is complicated. Creating a software startup is complex. An airplane is complicated. What happens between people on board is complex. An assault rifle is complicated. Gun control is complex. Building a skyscraper is complicated. Cities are complex.

Aaron DignanBrave New Work

Some other complex (adaptive)* systems to bear in mind:

  • Your body – and pretty much all of the parts within it
  • Your thoughts, perceptions, moods
  • Your family
  • Your community
  • A classroom / school / seminar / conference
  • A team or organisation
  • An airport / shopping centre / supply chain
  • A forest / the climate

Conclusion: Most of the institutions that are important to us are complex adaptive systems that are themselves made up of of complex adaptive systems. The downside of this is that simple cause and effect thinking is far less useful than in a complicated system. The upside is that the right kind of butterfly could cause a wonderful storm…

The book is excellent so far. Thanks to Sharky for the tip.

*More on ‘adaptive’ in a future post

**See also:
The wrapper
More than Reading
Deep literacy: what it takes

… and my forthcoming post, Machine. Ecosystem. – which has been sitting unwritten since September.

I'd love to hear your thoughts and recommended resources...