Jan Swammerdam

Swammerdam stands at the centre of the social world Peregrine both desires and dreads, a naturalist whose name carries the weight of real scientific obsession and whose rooms hold the alluring Dörtje Elverdink. Master Flea treats him as a genuine danger, urging Peregrine to refuse the invitation even at the cost of the flea's own safety, which gives the old scholar an almost magnetic pull in the narrative. His presence raises the story's central tension between curiosity and self-preservation, and his household is where Peregrine's will is tested against the abyss between what a man resolves and what actually happens.