In the early 1980s, Duccio Balestracci discovered in a Sienese archive two account books kept from 1450 to 1502 by a Tuscan peasant named Benedetto del Massarizia. Benedetto knew how to read but not how to write. Infected by the urban habit of detailed personal record keeping, he asked various of his literate acquaintances to put into writing the details of his daily affairs. The resulting account books offer an unparalleled glimpse into the economic and social world of late medieval peasants.