ABSTRACT
At first glance, the world seems a well-ordered and predictable place. The apparent order and stability of our day-to-day existence has allowed farming and civilisation to develop, regulated by the simple, customary changes of day and night, the tides and the seasons. At the scale of human lives, it seems that rivers flow steadily to the sea, mountains stay put at the horizon and sea level remains within the limits of the local tidal range.
