Most people use “complex” and “complicated” interchangeably, but these terms describe fundamentally different ideas.

A system is complicated if it has many parts that interact in predictable, linear ways. For example, a car engine is complicated. Its design may be intricate but each component’s role is clear, and the system can be fully understood and controlled. Complicated problems can be solved through expertise, rules and procedures.

On the other hand, complex systems consist of many interconnected parts that interact in ways that produce unpredictable and emergent behaviours. Examples include ecosystems, economies and urban traffic systems. These systems cannot be understood by analysing individual components alone; their behaviour arises from the dynamic relationships between parts.

Complexity is marked by adaptability, non-linearity and change. Unlike complicated systems, complex systems cannot be fully controlled (only influenced).

Building roads for the Msida Creek Project is complicated because it involves detailed planning and coordination of many steps, but the process is ultimately predictable. However, managing the traffic there is complex, as it involves the unpredictable behaviours of hundreds (if not thousands) of drivers and their responses to changing conditions.

Understanding the distinction between complexity and complication is crucial in science, as it influences how we approach problems and solutions.