César Aira - "Ghosts"

So, I finished "Ghosts" this morning - my first César Aria - and I'm not completely sure what to make of it. The book tells the story of a family of Chileans living on top of a high-rise set of condos being built in Buenos Aires. The father of the household is one of the builders and is paid a small additional sum to live there and guard the site. He lives in a small two room apartment on the roof of the building with his wife, four children and his step-daughter Patri. Oh, and a lot of ghosts, who are all male, float around naked, apparently covered in building dust, laughing a lot. The story takes place on New Year's Eve and follows the family from morning until midnight. And over the course of the book, these ghosts begin to take a special interest in Patri and she has to decide how to respond... The first fifty pages were pretty plain sailing, the tone reminding me of Queneau - funny and erudite and unpatronising about "ordinary people". But from page 57 to page 67 there is a very strange meditation on "the unbuilt," kind of disguised as Patri's dream. Now, I have no head for theory so I don't know whether it's accidentally gobbledegook or supposed to be gobbledegook or genius-level philosophy. It certainly made no sense to me. But once I'd got used to it making no sense the story got going again and I enjoyed it right to the end (which, I won't spoil). Sticking to Aira's principles about the necessary inexplicability of stories I feel under no pressure to make sense of the book for you. "How I Became A Nun" is next!