Understanding Complexity: What is a complex system?

People often talk about complexity, but what is complexity?

The word ‘complex’ gets thrown around a lot in our daily lives. The trouble is, it’s often misused to describe something that is difficult. Difficult and complex are not the same. A complex system has several characteristics that define it.

The Characteristics of a Complex System

1. Emergence: Complex systems often display emergent properties that are not evident in the individual components of the system. These properties emerge from the interactions among the components and can often be surprising or unintuitive.
2. Adaptation: Complex systems frequently have the ability to adapt or evolve in response to changes in their environment or internal state.
3. Nonlinearity: The interactions among the elements in complex systems are often nonlinear, meaning that small changes can lead to disproportionally large effects (or vice versa).
4. Interconnectedness and Interdependence: The components in complex systems are usually interconnected in such a way that changes in one component can affect several other components.
5. Feedback Loops: Complex systems often have feedback mechanisms that can either amplify (positive feedback) or diminish (negative feedback) the effects of changes in the system.
6. Hierarchies and Networks: Elements in complex systems often organize themselves into hierarchical or network structures, with different levels or clusters affecting each other in various ways.
7. History Dependence: The history of the system’s state can be important. This is known as path dependence, which means that the system’s past experiences influence its current and future behavior.
8. Stochasticity and Determinism: Complex systems often involve both stochastic (random) and deterministic (predictable) processes.
9. Multiple Scales: Many complex systems operate and evolve on multiple temporal and spatial scales, and these scales can interact in complex ways.
10. Robustness and Fragility: Complex systems often display robustness in the face of certain kinds of perturbations, yet can be very fragile when subject to other types of disturbances.
11. Self-Organization: Complex systems often show a form of organization without central control. They evolve patterns, structures, or behaviors from the bottom-up rather than being directed by an external orchestrating influence.
12. Edge of Chaos: Complex systems often operate at a “critical point” between order and chaos, where the system is neither too rigid nor too random. This is considered to be a space where complexity and adaptation are maximized.

Due to these characteristics, complex systems are often hard to describe, understand, predict, and control. Complexity science aims to study these systems using a variety of methodologies, including computer simulations, mathematical modeling, and empirical studies, to understand the principles that give rise to complexity and to apply these principles to problems in various domains.

Examples of complex systems:

1. The economy is a complex system. 
2. A city is a complex system. 
3. Human biology is a complex system.

Examples of systems that are not complex:

1. An air conditioning unit is not a complex system. 
2. A fridge is not a complex system.

What is it that defines the first list as complex systems and excludes the second list altogether?

When we give something the descriptive label of being complex, we are really saying that it consists of interdependent, diverse entities. We are also making an assumption- that the entities respond to their local and global environments in the form of adaptation.

Complex systems and the science of complexity are interesting to us (well, I can’t speak for you, but they definitely interest me) because they are often unpredictable, can withstand considerable turbulence/trauma, and can produce significant events.

As a business owner, your business could be considered a complex system. This is 100% true for larger businesses with large teams, large customer bases, and a diverse range of products, services, and responsibilities. However, if you are a team of one, your business is difficult but not complex.

Your business is a single entity among many. The many is the economy. As you already know, the economy is a complex system.

I chose to share this with you today because I have seen a group of self-proclaimed experts talking absolute nonsense on Twitter/X this morning, specifically about the complexity of their business. They were all freelancers. Freelancers with next to no clients between them. They were discussing their business’s complexity, but they needed to be corrected. Their business is not complex; it may be difficult, but certainly not complex. They were also trying to sell a course on how to make your business less complex.

Complex systems: Why do they matter?

If you are going to lay down your hard-earned cash for a course on reducing the complexity of your business, you need to make sure that the people selling the course actually understand what complexity is. This post is a brief introduction to a deep topic. I won’t bore you further by going deeper now, but I may do in the future.

The easiest way to differentiate between simple and easy, or complex and difficult, is to run it by this list:

• Does it consist of diverse (as in different types, not variations) entities?
• Are those entities interdependent?
• Do the entities respond to their local and global environment via adaptation? 

If you answered yes to the above questions, you are likely looking at a complex system.