In this lecture, you will learn how authors concealed their writings from prying eyes: they encrypted, changed names, wrote allegorically, hid notebooks, and sometimes destroyed them. Guests of the lecture will examine the diary as an ego-document that simultaneously strives for sincerity while building barriers. A teenager hides a notebook from their parents, an adult - from colleagues and neighbors, a memoirist - from a future publisher. They employ codes of their own invention, mix alphabets, use mirror writing, change languages, and avoid direct names. How do we read a diary that was not meant for us? What traces does the editor of the past leave - a person crossing out lines, removing pages, rewriting dates? How do everyday details - weather, prices, routes - help reconstruct vanished episodes? Allegory allows for the description of forbidden topics through images and metaphors; irony shifts the focus; repetitions work like a password understood only by insiders. Some authors keep records "for growth" - with an eye toward publication, but leave gaps that are only filled by historical notes. All entertainment in St. Petersburg is gathered on our website.