This has some really interesting material and I love Sacks' friendly, conversational writing voice, but the arrangement of the book was frustrating. Nearly every page has a footnote, which would often take up a good chunk of the page and maybe even continue on into the next, which I wanted to read(!) but it was jarring to keep leaping back and forth between thoughts. These footnotes were substantial enough in their own right that they could have been included in the main body of the book; I wish Sacks had simply done that. It would have been a lot more cohesive and easier to read. But the content itself was good.