This book places under sustained scrutiny some of our most basic modern assumptions about inheritance, genealogy, blood relations, and racial categories. It has at its core a deceptively simple question, one too often taken for granted: what constitutes "good" bonds among humans, and what compels us to determine them so across generations as both a physical and a metaphysical attribute? Answering this question is complex and involves a foray into a seemingly disparate array of early modern sources: from adages, common law, and literature about bloodlines and bastardy to philosophical, political, and scientific discourses that both confirm and confound the "common sense" of familial, communal, national, and racial identity.