This book establishes a character type that has come to be used in much fiction, "The Underground Man." I read a hypothesis that every society must necessarily produce underground men.

I've read some disagreements but my understanding of this archetype is, based on my reading of the book: a man/woman who recognizes his depravity in all sorts of actions due to powers of introspection and a commitment to truth, and yet is very willful and unable to simply stop these behaviors, but does not simply ignore or rationalize these (he may sometimes do that but he has lucid moments frequently and these make him miserable). As such he is inherently miserable.

His main problem is his willfulness. The first half of the book is the protagonist soliloquizing, not so much a story as an essay that includes examples from his life that are little snippets of stories. He uses these examples to argue several points, some of which I think we are meant to not necessarily agree with--I think he is an unreliable narrator, and this becomes even more obvious in the second half of the book--but the main point that he makes in the first half of the book that I find powerful is the idea of willfulness.

Basically, human wilfullness is irrationally wanting to get our will even when it's against our self-interests (money, respect, power, food, sex, etc, the things we naturally want). This observation tears down the idea that if we could only provide all of mankind's physical needs then the world would be a utopia.

The second half of the book, Appropos of Wet Snow, is a story out of his life that shows in more plain relief just how willfull, petty, selfish, the character is. It also shows a lot of great insights into social status problems.

I loved this book, it was a quick read actually, surpisingly, and a great delve into character and questions of human nature.