Civilization exists by geologic consent…

Civilization exists by geologic consent, revocable at any time. – Will & Ariel Durant

In a few hours, as many as 25,000 people will begin assembling at in the pre-dawn gloom at Lotta’s Fountain for the 100th anniversary of the 1906 San Francisco quake. It will be a celebration tinged with the gnawing certainty that one or more great quakes will visit the bay area again in the lifetimes of most of the people assembled.

Remarkably, San Francisco grew right back in the place where it was destroyed. Just as Lisbon did after the 1755 quake that leveled that city. And just as New Orleans is rebuilding again, below sea level behind puny dikes certain to be overwhelmed eventually by a hyperactive weather engine fueled by global warming. Now San Francisco is celebrating a disaster certain to repeat itself, the celebrants whistling nervously past a 100 year old grave.

It is easy to wonder why anyone would build in such dangerous places — but the real question is why would anyone build anywhere else. Life — whether biological or commerical– thrives at borders. Cities are no exception. New Orleans, like Venice, Hong Kong, Shanghai and myriad other port cities is located at the logical trans-shipment point between river and ocean. And San Francisco’s geographic advantage at the head of a vast natural bay was shaped by the very faults that once destroyed it and threaten it again now. Cultures no less than individuals take risks, and Civilization does indeed exist by geologic consent, revocable at any time.