Here’s a hugely impressive book, and I feel smarter and more understanding after reading it. Diamond writes a beautiful message: all societies are inventive, but the environments and starting materials, conditions are not the same. And most of it is based on the narrative of Yali’s question, an elegant and honest search that shows the interconnectivity of everything, and doesn’t attribute history to single causes. My only comment is that it should have been shorter by 200 pages. The book doesn’t decide between pleasing to everyone, and being anthropologist and history textbook. Chapter four feels like an afterthought of loose chapters, as well as the epilogue and afterword. At least I ran out of steam.