The first paragraph, and the one directly above the one about knowing more about furniture:

> There is a theory, popular among certain very old and very tired philosophers, that all memories take up a kind of furniture in the head. The good ones are armchairs. The painful ones are filing cabinets, usually full. And then there are the memories that are neither: the ones that arrive uninvited, settle in, and start terrorising the other occupants by kicking over the chairs.