From time to time, I come to own books that other people have discarded. This is not because I am so depraved a bibliophile that I rummage around in rubbish bins, but is rather a result of my capitalizing on being around bookish folks when I am one, myself. People clean out their office spaces, and among what they set aside are often the bound pages of books.
Frequently, those pages abound with marginalia. Many of the texts I acquired from where professors and others had left them on tables, free for the taking, have been liberally provided with comments at the edges of pages or squeezed somehow into the tiny spaces between lines of text--and there have been a few times when such marginalia has proven quite useful. I am sure that anyone who takes up a text from my own working library (rarely; I do not often get rid of books, particularly those I use to inform my scholarship) will find much the same thing (provided, of course, that my handwriting can be surmounted). I entertain the hope that it will be of help.
If happens occasionally that I find something a bit more...substantial than notes on the page, however. For instance, I recently came into possession of a copy of Luce Irigaray's Between East and West: From Singularity to Community (trans. Stephen Pluháček; New York, Columbia UP, 2002; print). The previous owner had left in its pages a bookmark, wedged between pages 112 and 113; when I found it, I found myself forced to wonder why it was there, working through some questions. I am still not sure I have a good answer.
Had the earlier reader simply stopped reading at that point and never opened the text again? Unlikely, since a reader who leaves a book behind will typically take the bookmark away. There is no need to mark a page in a text that will not be revisited, after all, and the bookmark itself could be put to use in another work entirely. Too, the position of the bookmark is a bit strange for interrupted reading, as it is not at a section or chapter break--and I, who read much, work to leave off only when the text does. Irigaray is not light reading, so I can only posit that the earlier reader was similar to me in dedication to the work of interpreting text.
Does the marker mark a passage of importance? Possibly, for although there was no marginalia in the book when I got it, the two pages which hold the bookmark found themselves covered in my markup. They discuss issues of female civil identity and the problems attendant on its lack--serious subject matter, indeed. But this is true of other parts of the book, some more powerfully put than what the bookmark marks (at least to my thinking). So I am not sure that it stands out particularly prominently--unless there is something of significance for the earlier reader that I miss.
So, the earlier reader forgot the bookmark? Also possible. And I seem to have misplaced one, myself...