Genos in ancient Greek is a two-sided concept that denotes lineage or genealogy on the one hand, and kind or category on the other. This talk is excerpted from a larger project that investigates the gendered stakes of this twofold notion as it travels from myth and tragedy into the texts of philosophy. Plato’s Sophist foregrounds both dimensions of genos, the genealogical and the categorial. Attending to this ambivalence within genos turns out to be a revelatory optic for deepening our understanding of this notoriously difficult dialogue, and for approaching Plato more generally.