Last week, in celebration of its centennial, the Frans Hals museum in Haarlem had on view the largest exhibition of Hals paintings ever held.

Until they opened a museum in the summer of 1862, the burghers of Haarlem in The Netherlands never fully realized the extent of their riches. There had been paintings in various public buildings all over town, but now they were assembled under one roof, and the effect was dazzling. The…