The first paragraph should give you some idea of what it's about:
The subject of this paper is not Wittgensteinian ethics but Wittgenstein’s own ethical beliefs, specifically as these are revealed in the so-called Koder diaries. The word ‘diaries’ might make one hesitate to read this material, let alone discuss it in public. But, as James C. Klagge and Alfred Nordmann note, “On first sight, this manuscript is not at all dissimilar from Wittgenstein’s other notebooks.”[i] While the Koder Diaries, also known as Manuscript 183, do contain the kind of thing that one would expect to find in a diary (e.g. accounts of travel and personal relationships), they also contain more obviously philosophical remarks too, sometimes as reflections on these personal remarks. It is perhaps not surprising, therefore, that, “As opposed to his other notebooks and the so-called secret diaries of 1914-1916, the Koder diaries are unique precisely in that they do not set off the private from the public at all.”[ii] Even the remarks written in code are not clearly more personal or less philosophical than the others. It seems to me, therefore, that the Koder diaries are an especially interesting kind of document, and, as I hope we shall see, that Wittgenstein’s ethical reflections in them are unusually interesting, even if they resist being summarized in one or more ethical theses or points.