A system is more than the sum of its parts

Meadows defines a system as a set of elements interconnected in a way that produces its own pattern of behavior over time — a tree, a economy, a thermostat, a family. Crucially, the behavior comes from the arrangement, not the individual pieces. Swap the parts of a system with different but structurally similar parts (a different manager, a different currency) and the behavior often persists unchanged.

This is why she insists you can rarely understand a system by understanding its parts in isolation. Dissect a bicycle and you learn nothing about traffic; study a single ant and you learn nothing about the colony's logistics. The interesting behavior — resilience, oscillation, collapse — lives in the relationships.

Her practical corollary: when a system misbehaves, resist the urge to find the broken part or the guilty person. Usually nothing is broken; the structure is simply generating exactly the behavior it's built to generate. Fix the structure, not the scapegoat.