In three centuries the heresies of two bankers became the basis of our modern economy. When the Venetian merchant Marco Polo got to China, in the latter part of the thirteenth century, he saw many wonders—gunpowder and coal and eyeglasses and porcelain. One of the things that astonished him most, however, was a new invention,
Like many medications, the wakefulness drug modafinil, which is marketed under the trade name Provigil, comes with a small, tightly folded paper pamphlet. For the most part, its contents—lists of instructions and precautions, a diagram of the drug’s molecular structure—make for anodyne reading. The subsection called “Mechanism of Action,” however, contains a sentence that might induce sleeplessness by

