'The Bibliothèque du Roi is just a house, you see, a house Colbert happened to buy on the Rue Vivienne – probably as an investment, because that street is the center of goldsmiths. Every ten days, from ten in the morning until noon, all of the merchants of Paris send their money to the Rue Vivienne to be counted. I sit there in Colbert's house trying to understand Descartes, working the mathematical proofs that Huygens, my tutor, gives me, and looking out the windows as the street fills up with porters staggering under their back-loads of gold and silver, converging on a few doorways. Are you beginning to understand my riddle now?'