 Willem is speculating in the tulip market, and is doing quite well - expecting to be independently prosperous and able to marry Maria, he even sells his business to another fishmonger.One day, Sophia borrows Maria's cloak and heads to a rendezvous with Jan. Willem, seeing Sophia in the cloak, mistakes her for Maria, and follows her to her rendezvous.Crushed by what he thinks is Maria's unfaithfulness, he goes to a pub to drown his sorrows.