Genli Ai is a lone human emissary to Winter, an alien world whose inhabitants can choose - and change - their gender. His goal is to facilitate Winter's inclusion in a growing intergalactic civilization, but to do so he must bridge the gulf between his own views and those of the completely dissimilar culture that he encounters.
I first read this book in 2011 and already then I knew that I would read it again. The timing of me re-reading it wasn't entirely my choice but in the end that didn't matter at all. Because I knew what was going to happen it was as if my brain was free to notice things I didn't notice 2 years ago - the poetry of the language, the beautifully crafted story, the meaning of the folklore and excerpts of historical records inserted between chapters, the echoes of the philosophy of ying and yang throughout the book, the notion of true gender equality and its consequences. I noticed how perfectly the ending of the novel mirrored its beginning, recognizing the similarities between a keystone being placed in an arch to connect the separate sides and Therem Estraven being a similar kind of keystone that would link two separate branches of humanity. I finally fully understood the title of the book, which made me feel that I understood nothing the first time around. I realized that this novel isn't really about Genli Ai, even though he is the narrator most of the time. It is about Estraven, his vision for Gethen, and about following a path which others can't even see.
Like many other science fiction novels this book isn't about the planet or the technology, but rather about people, human nature and everything that comes with it, such as patriotism, love, deceit, faith and Truth. Yes, it's a lot to talk about in a book that is not at all hefty, but that is where Le Guin's brilliance lies. She doesn't need 600 or more pages to ask questions, ponder answers, observe and make the reader think. Half of that does very well.
I'll keep this review short because what I really want to tell you is that this is an amazing book, that I'm buying it for my collection and that if you haven't read it yet you should, even if you're not a fan of science fiction.