Exploring such questions as "how did fact become modernity's most favoured unit of knowledge?", this text contains ideas and texts from the publication of the first British manual on double-entry bookkeeping in 1588 to the institutionalization of statistics in the 1830s. It shows how the production of systematic knowledge from descriptions of observed particulars influenced government; how numerical representation became the privileged vehicle for generating useful facts; and how belief - whether figured as credit, credibility, or credulity - remained essential to the production of knowledge.