Through the story of the Perraults, a family of literary and scientific authors active in seventeenth-century Paris, the book argues that kinship networks played a crucial yet unexamined role in shaping the cultural and intellectual ferment of seventeenth-century France, while showing how culture in its turn shaped kinship and the social history of the family. The book examines the world of letters as means of social mobility and revises our understanding of prominent early modern institutions, such as the Academy of Sciences, Versailles, and the salons, as well as authorship and court capitalism. Put together, this project serves as a catalyst for rethinking early modern cultural and intellectual institutions more broadly. In this view, institutions no longer appear as rigid entities that embody or define intellectual or literary styles, such as “Cartesianism,” “empiricism” or “the purity of the French language.” Rather, they emerge as nodes that connect actors, intellectual projects, family strategies and practices of writing, thereby reframing their relation to the state.