Rating Sapiens has so much to do with what kind of book you think it is. Suppose you are expecting a rigorous academic treatment of all of world history. In that case, you will be disappointed at best and alarmed at worst. But Harari is aiming for something other than a precise blow-by-blow of world history. He is writing for people who took a newfound interest in history and are asking questions like, "How did we get from caveman to here?" I want to be slightly abrasive and say he writes for people looking to pick up a few opinions for their following dinner conversation. And within that framework, he does a good job. Almost.
Popular science, in this case, popular history, will simplify and overlook many finer details. It is challenging to make academic research available to the layperson. Therefore, asking questions like, "How accurate is Sapiens?" is not a good way of rating the book. There is a paradox because how is a premise supposed to hold up if the evidence supporting it is inaccurate? But while reading pop history, we shrug our shoulders and accept a few errors as long as the basic idea gets through.
The problem with Harari is that he takes this over-simplification to another level and distorts well-known history to fit his overall structure. His ideas about evolution (that it created a "struggle for dominance") and his complete erasure of human states that didn't need ideas like writing or the "cognitive revolution" is frankly unnecessary. The point could've been made without these inaccuracies, which begs why he needed to explicitly make these mistakes. The entire chapter about Science, the Industrial Revolution, and Colonialism is excellent if you want to write a history of H. Sapiens in Western Europe. Harari mentions other countries' inventions but waves them away as not natural science because they don't fit with his chapter names like "The Animal That Became a God." Whether you want to give him the benefit of the doubt here is a personal choice, but like before, sweeping all this under the rug was unnecessary.
It gets comical when you get to the blatant inaccuracies. Harari has a single line about the French Revolution that is, drum roll, plain wrong. There is an excellent comment on r/AskHistorians taking it apart. Beyond that, Harari's own thesis advisor in a New Yorker profile admits that his student dodged fact-checking "by saying, 'Let's ask questions so large that no one can say, We think this bit's wrong, and that bit's wrong.'". My personal favourite was in a Current Affairs article where a biologist points out a line in the book about chimpanzees, that they "hunt together and fight shoulder to shoulder against baboons, cheetahs and enemy chimpanzees" and then goes on to say how that's just not possible because cheetahs and chimps don't even live in the same parts of Africa. Suppose you can't trust him to get the small innocent details right. How do you take him seriously on the big heavy ideas he casually throws around?
Sapiens was the first non-fiction book I read that wasn't an autobiography, and I loved it immediately. It made me feel smart. It made me feel like I understood the world more subtly. Everything was a construct, money, nation-states, religion, language, writing, capitalism. It gave me more things to opine about than the other person. I tried to re-read it a few years after that. I just couldn't stand all the posturing and unnecessary oversimplification of historical ideas that didn't need his cosmetics. They were perfectly wonderful on their own, and Sapiens just ruined them.
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