In the days before Richard Dawkins gained his Delusion(al) fame, he put forward a very useful metaphor for understanding complexity:

A dead parrot thrown up into the air obeys the laws of physics, forms a perfect parabola, and then falls back to earth. A live one disappears over the fence; its component parts working together to maintain their collective entity against the force of gravity.

This helps explain why, as managers, our employees/customers/suppliers don't "fall back to earth" like we'd like them to. We are dealing with levels of complexity in human systems that defy prediction and patterns of behaviour that defy causal links.

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