This book says that we don't want to lead lives of slothful leisure, despite what advertisements for beach resorts tell us. We want to do things that keep us engaged. We want fun challenges where we get an immediate sense of accomplishment. The good news is that I agree with this. The bad news is that the book just asserts these things and says that the evidence for them is in the sources referenced, uhm, in the endnotes. Oh dang. There are some anecdotes in the main flow of text, but of course you're not going to base your theory of human happiness on a few anecdotes, right?
So I read this book, kind of nodding along saying "Amen, sing it brother," but I didn't learn anything I could use to convince someone to stop idling on the beach.