Love as Passion: The Codification of Intimacy (Cultural Memory in the Present Series) Book

I liked this book a lot. Turns out the supposedly foreboding systems theorist Niklas Luhmann was partial to old romance novels. His research into them, especially ones written in the 18th century, is fairly exhaustive. And he reconstructs a conceptual history of love, marriage, and sexuality from them. His theory of intimacy, clarified in the last two chapters, is also very interesting, and it gives an excellent example of how his more general theory of social systems works both at the microsociological and macrosociological level. I won't try to describe the contours of the theory here.
One thing I will say against this book is that the writing is not always as clear as could be, even for Luhmann. I'm not sure if this is due to the German or due to the translators. The consequence is that this book takes quite a bit more time to unpack and digest than it's page count would suggest, which isn't a wholly negative thing.