Added at the very end of a 14th century roll of Peter of Poitiers didactic Compendium historiae in genealogia Christi, this diagram orders the many kinds of vices that befall humanity. Each is named within a small, coloured roundel, which are either connected by coloured bands, or string together to form chains or clusters. On the 17th of September, Jeffrey F. Hamburger led us through the Comites Latentes Collection currently housed at the Universitätsbibliothek Basel. After discussing Hamburger’s most recent book project “Spaces of Knowledge in Medieval Diagrams” in the morning, this manuscript was the most diagrammatic we saw that afternoon. Despite its formal reduction to circles and lines, it showcases the way diagrams form thinking just as much as they depict it. On the page, the vices stand in multi-dimensional relations to each other, as they form amorphous clusters, divide and reconnect.