Ursula le Guin's science-fiction novel about a world where people are not women and men except for the short time period of getting into a sexual heat and the consequent pregnancy should the heat take that form. It is an astonishing book in so many ways, because I think we are almost inherently incapable of building or understanding such a genderless world in a way to make it comprehensible, and she succeeds better than any other writer I've read.
Better than any other writer I've read, but not necessarily terribly well, simply because it is so very hard to see the invisible web that connects sex to all the other human constructs and then to cut those threads. Le Guin's genderless world still has power hierarchies, poverty and inequality, and I believe that she is correct in creating them. But I'm not sure they ring true to me in the absence of gender-related hierarchies and ownership rules. That is most likely not her fault but a flaw in my own imaginary capacities. Still, at the end of the book I had gained a distance to our own societal structures and a small amount of new insights into the role of sex roles.
If you haven't read the book do read it. It is well worth the initial effort required.
The reason I'm writing about The Left Hand Of Darkness is that I visited le Guin's website where she gives the rejection letter she received for the book:
Dear Miss Kidd,
Ursula K. Le Guin writes extremely well, but I'm sorry to have to say that on the basis of that one highly distinguishing quality alone I cannot make you an offer for the novel. The book is so endlessly complicated by details of reference and information, the interim legends become so much of a nuisance despite their relevance, that the very action of the story seems to be to become hopelessly bogged down and the book, eventually, unreadable. The whole is so dry and airless, so lacking in pace, that whatever drama and excitement the novel might have had is entirely dissipated by what does seem, a great deal of the time, to be extraneous material. My thanks nonetheless for having thought of us. The manuscript of The Left Hand of Darkness is returned herewith. Yours sincerely,
The Editor
21 June, 1968
Now imagine if she had given up at that point.
Added later: I'm not sure if my impression is the correct one, but I think that these sorts of books in science-fiction are mainly written by women? By "these sorts" I mean books which study gender roles in the context of fantasy, not books which tell the story about the lone guy being dropped on the planet of sex-hungry heterosexual amazons who nevertheless live without men.