The builders of Stonehenge five millennia ago revered the long cycles of time. Their monument measured the annual rhythms of the sun from equinox to equinox and the subtle 18.6-year oscillations of the rising moon. Through a hundred generations, they revised and recalibrated their circles of earth and stone to bind their lives with celestial time. 

A world away, under the tropical sun, Mayans identified their place in time within expansive overlapping patterns of days. Their Long Count calendar encompassed cycles that stretched 5,000 years, from the primordial origins of life to the imponderable beginnings of a new era.

Our own highly regulated time never seems so expansive. We live in tight temporal patterns. These begin with a momentary, global celebration that rolls from New Zealand...