What is the difference between a complex and a complicated system?

Complicated systems are highly predictable; complex systems are the complete opposite. Understanding the distinction between the two is necessary for organisations because, to date, they have mostly viewed the world as complicated and, therefore, something they can control. What is increasingly evident is that the world is, in fact, complex and unpredictable and we must accept and adapt to this to succeed.

What do these systems look like?

Complicated systems, such as a car engine or a 747 aeroplane, are made up of parts that work together to achieve the desired outcome. Crucially, everything can be mapped out and (if we invest the necessary time) understood. We might find complicated situations confusing, but the relationships between the various parts are predictable, so we know what will happen if we change something.

In complex scenarios, it is almost impossible to predict what will happen when we change something, even in cases where there are only a few parts. For, in complex systems, such as a bowl of spaghetti or a game of chess, the number of interactions between components increases rapidly and dramatically. Unlike complicated situations, we almost certainly can’t control them. The best we can do is to guide and respond.

Take our game of chess. There are around 197,000 options for the first two moves. By the third move it’s 121 million, and by the 20th, the chances are that you’re playing a game no one has ever played before. The exponential growth in options is due to the interdependence of the relationships: move one piece, and the relationships between all the others change at the same time. We don’t win chess through control; we win through responding to what’s in front of us and guiding it over time.

Why the shift from complicated to complex?

For 300 years, the normalised worldview has seen the universe through the complicated lens. Rooted in the work of Newton and Descartes, this is the mindset of rational thought and deterministic relationships. But the world is not complicated; it is complex. Moreover, the pace of technological change and proliferation of information that we now experience is increasing the complexity of our global environment at a rate unique to human history.

To use a recent, although dramatic example: when Mohamed Bouazizi set himself on fire in a Tunisian market in 2010 no one could have predicted it would spark widespread unrest across the Middle East, the end of Mubarak and Gaddafi and the start of a civil war in Syria. But 200 years ago, without the proliferation of influencers such as 24/7 media channels and communication networks, the fallout would likely have been far more localised.

For organisations to succeed in the 21st century, they will need the lens of complexity to embrace unpredictability: they must stop trying to build engines and start playing chess.