For want of a nail, the shoe was lost;
For want of a shoe, the horse was lost;
For want of a horse, the rider was lost;
For want of a rider, the battle was lost;
For want of a battle, the kingdom was lost;

..., it is well known that a chain of events can have a point of crisis that could magnify small changes. But chaos meant that such points were everywhere. They were pervasive. In system like weather, sensitive dependence on initial conditions was an inescapable consequence of the way small scales intertwined with large.

James Gleick,
Chaos - Making a new science