The Blank Slate, Steven Pinker
This took me a really long time to read (see below), because it often gets into this subtlety thing that I just didn't feel like unraveling.
What I did unravel is that some of us have been taught to feel guilty for Western society's achievements, and that perhaps even more of us has gotten used to thinking that reason is the only human faculty worth mentioning. It is therefore stimulating to think that what defines a human being is not just reason, but other faculties and idiosyncrasies that exploration of which may lead to more targeted invention, or more striking art.
Let's not forget that Pinker's a pretty funny guy, and writes very approachably. But he takes on problems of large magnitude: what happens when individual instinct goes up against a carefully constructed community convention? The Language Instinct was more fun than this, and in Blank Slate, it's surprising how much subtle argument goes into a conclusion that Pinker himself admits is self-evident. The book is an academic navigation, a very careful one, and appreciable for the quality of its thought and writing, not for its pull.