Iain Banks is dying. That's not supposed to happen, and I'm quite dissatisfied with this turn of events. I would register a grievance to the appropriate authorities, but Special Circumstances won't answer.

Banks produced a body of work that was deeply engaging and often darkly satirical. Perhaps his greatest achievement was the Culture series, a science-fiction universe of massive scope, grim wit, and oddly self-defeating optimism. The last novel in the series centers around the last days of an advanced civilization that has decided to simply walk away from this universe. I wonder now if that's not …

Iain Banks' Culture series doesn't lend itself to easy summations. Entire essays have been written on the world he set up, so I won't go into much detail.

Essentially, Banks has created a liberal utopia on a galactic scale. Given a limitless supply of easy energy and near-omnipotent manufacturing technology, the citizens of the Culture want for nothing material. Tedious administration is done by artificial intelligence, leaving normal folks to live their lives as they please. In such a society, property is an archaic concept, something that is even reflected in their language. With scarcity removed from the equation, the only real crime is coercion.

Still, every society hits a wall eventually. In Banks' world, self-destruction or a collapse into barbarism is unlikely, and the end point for civilizations is simple ennui. What do you do when you just feel like you're going through the motions, with nothing left to contribute?

Well, there's always suicide.

~ "God that thing is ugly," Huyler said when they first saw it, riding across from the wreck of the Winter Storm in the tiny shuttle with the ship’s black-skinned, gray-suited avatar.   "And these people are supposed to be decadent aesthetes?"

~ "There is a theory that they are ashamed of their weaponry. As long as it looks inelegant, rough and disproportionate they can pretend that it is not really theirs, or not really a part of their civilization, or only temporarily so, because everything else they make is so subtly refined."

Look to Windward is (chronologically) the second novel of Iain M. Banks' Culture series.  In his mythology, the Culture is a post-scarcity society, facilitated by artificial intelligences and near-perfect manufacturing technologies.  The human lifespan averages four centuries, and the people want for nothing.  The political structure is a benign anarchy, with policy decisions made largely through direct (and instantaneous) democracy.

In short, the Culture is a liberal utopia.