The traditional approach to understanding complex systems has been reductionist, breaking them into smaller, simpler components. While effective for understanding mechanical systems like clocks, where each cog serves a clear purpose in isolation, this method falls short when applied to dynamic, interconnected systems like living organisms, ecosystems, weather patterns, or even social structures such as economies, organizations, institutions, supply chains, or families.
To look at systems like these and only see parts is to miss the force that ties them together.
[…] You don’t understand rainfall by breaking a cloud down into its component pieces and glueing them back together.
Robert Sapolsky, in his extraordinary Human Behavioral Biology online course
Complex, interdependent systems defy simple explanations because they are more than the sum of their parts due to intricate behaviors and feedback loops. Such systems exhibit emergent properties, meaning that some characteristics and behaviors emerge at the system level that are not present in the individual components.
Understanding a complex system requires looking beyond individual elements and focusing on the relationships and dynamics between them, which opens the doors to a new field of science called systems science.
You think that because you understand ‘one’ that you must therefore understand ‘two’ because one and one make two. But you forget that you must also understand ‘and.’
Donella Meadows – Thinking in Systems: A Primer
Another characteristic of a complex system is nonlinearity, meaning the relationship between cause and effect is not proportional or straightforward. Small changes can have disproportionately large and unpredictable consequences, as seen in the “butterfly effect,” where a minor action, like a butterfly flapping its wings, can influence weeks later the details of a tornado (e.g., time of formation or the path taken). This sensitivity makes optimizing one aspect risky, as even well-intentioned adjustments can ripple unpredictably through interconnected layers, complicating decision-making.
The aim of science is not things themselves, as the dogmatists in their simplicity imagine, but the relations between things; outside those relations there is no reality knowable.
Mathematician Henri Poincaré – Science and Hypothesis
And so, understanding complex systems requires appreciating the role of context. The same intervention or change can have vastly different effects depending on the specific circumstances, history, and interactions within the system. The solution that breathes life into SystemA system can just as easily harm SystemB.
Our modern focus on the narrow, brutal logic of efficiency, especially in systems like the economy, has driven us toward a “machine model” of optimization, where the goal is to maximize output and eliminate waste. While efficiency brings certain benefits, an excessive pursuit of it often overlooks the need for resilience — the ability to absorb shocks, adapt, and recover from disruptions. So it follows that resilient systems often contain some sort of “slack,” a redundancy buffer against unforeseen challenges.
In the dominant machine-based model, slack, which is equated with waste, must be eliminated in order to maximize the machine’s efficiency […] Deming [American statistician and management consultant who played a crucial role in transforming Japanese manufacturing and quality control systems after World War II] himself recognized the systemic complexity of businesses and taught that there is always an optimal level of slack for any business system—and that level is not zero. Slack is a manifestation of friction, of the sort that in the right amounts contributes to greater resilience.
Roger L. Martin – When More Is Not Better: Overcoming America’s Obsession with Economic Efficiency
And what are humans, if not complex systems within systems within systems within…? When we often operate at high capacity, there is little room for essential elements like rest, reflection, or even a touch of randomness. Unless we deliberately step back, slow down, pause, or set boundaries, we risk running on empty. Yet, just as ecosystems rely on diversity and redundancy to thrive, human well-being also depends on having a buffer against life’s unpredictability.
This buffering, or slack, can be either deliberate or unintentional. Both have their merits. Intentional slack allows us to recharge, think clearly, and create space for strategic pauses. Unintentional slack emerges naturally (a meeting ending early), offering unstructured moments that allow spontaneity, creativity, or a quick recovery. At times, these two forms of slack merge, layering pause upon pause like infinite upon infinite, still yielding the same infinity.
The etymology of “slack” adds a subtle layer to its meaning. It is rooted in Old English slæc(originally meant inactive, slothful, lazy, unwilling to make an effort), and it has cognates in Latin laxus or Sanskrit श्लक्ष्ण (tender, soft). In Latin, laxus, from which we get “lax,” specifically means “wide,” “spacious,” or “roomy.” This older sense of slack as openness, yielding spaciousness contrasts sharply with the modern notion of slack as wasteful or lazy.
And just like open-ended infinity, slack perhaps recharges us. Perhaps it sets us back. It depends on how we let it flow.
Do I slowly empty
Or fill myself?
The same flow of sand,
Whichever way
You turn it.
Marin Sorescu – Hour-glass
Translated by Michael Hamburger
Related article series:
Perverse Incentives – If unchecked, pursuing efficiency can incentivize harmful behaviors.