A casual remark, a chance encounter in the corridors of power, decisions made at the administrative level; those are the things disasters are made of. We didn't know this until September 11, 2001.

What is a disaster? Natural and social causes, like separate strands, are closely intertwined. In the 5th century, attributing earthquakes to natural causes was a crime: there is a heresy that claims that earthquakes are supposedly caused by the elements of nature rather than by the righteous judgment and wrath of God, quoth Saint Philastrius. It took 14 centuries to replace this paradigm with another: one should not view God as an irrational being, capable of destroying His own temples, in the words of Camilo Henriquez, S.J., after the 1822 Valparaiso earthquake. This was a giant step forward, but it was not enough. We now realize that all disasters are social, as well as natural.