Netherton grimaced, seeing a patch of tabletop come uneasily to life, the sight of assemblers too nakedly at work abruptly nauseating him. Invisibly small, swarming in their billions, manipulating matter at a molecular level, they called into question the validity of every distinct category of thing. Chalk might be cheese, or cheese chalk, where assemblers were concerned. That they animated Ash’s demi-bustle, or her former tattoos, or for that matter Thomas’s nanny, was tolerable, but one never wanted to see them at it, overt chaos, the eye reading it as some grave and sudden defect of vision.