The Engineering Mindset Part 4: Complex or Complicated? There are no silver bullets

Chris and Penny Hamlin say that in complex systems, the path to success is never a single solution, but instead a dynamic mix of approaches that co-evolve

OUR LAST article discussed how spans of control and influence are important in complex systems and how cooperation and collaboration can extend these into areas that initially seem impossible to reach.

In this article we explain why in complex systems there is no single best path to any desired outcome. Once you understand this, then your focus can shift from an optimising approach to one that builds resilience and robustness for any given context and point in time.

To illustrate this, we will once again draw on our experience with the C-THRU research project, looking into greenhouse gas emissions in the petrochemicals industry.

Seeing the wood…

Ordered, linear approaches search for a single, uniform, best solution for any given problem. However, in complex systems any quest for a mythical silver bullet is both flawed and foolish for two reasons. Firstly, there is never a single, unique solution in a complex system that works equally well in all situations, but rather there is a multitude of option combinations that could resolve the current issue more effectively than any individual approach. Secondly, any combination of solutions that works in one system is unlikely to have the same effect in another system, or even work again the same way within the same system.

To illustrate, consider a forest. Monoculture forests, planted with a single tree type, lack the diversity needed to build resilience and adapt to changes, making them more vulnerable to environmental threats like disease and wind. Such systems are unsustainable as they deplete natural resources and hinder regeneration. In contrast, good forest management supports a variety of plant and animal species, fostering symbiotic relationships that enable renewal and resilience. No one species or organism exists in isolation, nor can it survive without interaction and co-dependency on the rest of the system. Biodiversity is essential, but only indicative of the potential of the forest to build strength and resilience through interdependence and synergy.

In general, complex systems require a diverse mix of solutions to thrive. Each system’s context – such as its environment or specific challenges – demands tailored approaches that evolve and adapt, rather than relying on a one-size-fits-all solution. For example, there are multiple types of renewable energy generation options and no single solution is best for all contexts – wind farms may be ideal in one country, while solar panels are more effective in sunnier climes, but both are constrained by environmental factors. Similarly, the ways in which limited quantities of renewable energy are utilised cannot be prescribed. In some countries, using the limited amount of renewables for electric vehicles might have a greater impact than electrifying industrial processes, while in others the opposite may be true. The same could be said for the impact of using green electricity for AI datacentres as opposed to domestic space heating and cooling.

…and the trees

The forest analogy highlights how individuals, organisations, and solutions emerge and evolve within broader systems. Just as an oak tree produces far more acorns than will grow into trees, many ideas and innovations never come to fruition or are adopted in unexpected ways. Some acorns fall in the wrong place or fail to germinate, reflecting how many ideas fail to gain traction or meet their potential. However, when a seedling takes root, it begins to draw resources from its environment, enabling growth. This process mirrors how new ideas or innovations require external support and resources to thrive, gaining momentum as they draw on a wider network. No idea emerges fully formed and commercially viable. For example, over the last 20 years solar panels have become amazingly more cost effective as manufacturing techniques have evolved and economies of scale have been realised. Hopefully, similar trajectories will occur with pyrolysis routes for the potential circularisation of petrochemicals and plastics production systems, and for bio-based alternatives to fossil fuel feedstocks.

Not all saplings become mature trees; most are overtaken, get eaten or fail before they can grow strong enough to survive. Yet, these early-stage failures contribute valuable energy and resources to other, more robust organisms, strengthening the overall system. This is akin to successful organisations that view failure as a learning opportunity, rather than something to avoid. As a tree grows and matures, it eventually reaches a state of homeostasis, where its potential for growth is balanced by external constraints such as competition for resources. New ideas or innovations similarly reach a point where growth slows or stabilises due to limitations or competition. For example, conventional CCS is inherently limited by the ability to collect and concentrate CO2 emissions for diverse sources. We currently don’t know the extent of its viability or how its practical limit will shift over time, and where the eventual limit will be.