L’essentiel est invisible pour les yeux. (“The essential is invisible to the eyes. ”)
—ANTOINE DE SAINT EXUPÉRY, LE PETIT PRINCE
On September 8, 1999, a worker on the Big Dig, Boston’s mammoth road and tunnel project, noticed a problem. Several recently installed anchor bolts were slipping out of the roof of the tunnel, displacing about one-sixteenth of an inch. These bolts, secured by an epoxy, held up large concrete ceiling panels, and if the bolts separated from the roof, the heavy concrete panels would fall directly onto the roadway below.1
Over the next several weeks, workers noticed the displacement increasing.
In December 1999, the management duo of Bechtel and Parsons Brinckerhoff, the private consortium ...