Ideas have a history, but so do the tools that lend disembodied ideas their material shape −− most commonly, text on a page. The text is produced with the help of writing tools such as pencil, typewriter, or computer keyboard, and of note-taking tools such as ledger, notebook, or mobile phone app. These tools themselves embody the merging of often very different histories. Lichtenberg’s notebooks are a good example, drawing as they do on mercantile bookkeeping, the humanist tradition of the commonplace book, and Pietist autobiographical writing (see Petra McGillen’s detailed analysis).