Podcast: Aaron Dignan on complicated vs complex


  • An engine is a good example of complicated. If something is broken, we can use process and past knowledge to diagnose a fix.
  • A complicated system has a cause & effect relationship between its components.
  • This implies predictability. It’s a knowable thing


  • Whereas venturing into an unknown area is complex as you can’t just rely on standards, procedures, and past knowledge.
  • Examples include weather, traffic, immune system
  • They are dispositional systems, they operate in a vector space. Although we have an idea that x will happen because things are trending in that way, we can’t fully predict what’ll happen.

The only way to understand a complex system is to interact with it.

Key take away:

Lots of businesses try to solve complex problems with mental models from solving complicated problems.

Standards vs Defaults

  • Standard: “This is the way we solve the problem, and everyone agrees on it”
  • Default: “If you don’t know any better, try this”
  • Shuhari framework?

on Metrics

  • Metrics are a proxy for reality, not the whole story. easy for them to miss nuance.

Behind the scenes

Listened to this on 19 April 2023 - or at least, that’s when I made the handwritten notes. I just found that handwritten note while doing a little bit of tidying up and decided it was worth persisting on the internet