In "Sapiens: A Brief History of Humankind", Yuval Noah Harari sets out to tell the story of Sapiens' early beginnings, the revolutions that shaped us (cognitive, 70000 years ago; agricultural, 11000 years ago; scientific, 500 years ago; industrial, 250 years ago; and finally information 50 years ago), and our possible future from the coming "biotechnological revolution". The potential for an interesting and insightful book was there, however, Harari squanders it on poorly researched, poorly referenced, or usually no referenced at all, and opinionated misleading sensationalism.
Harari is a professor, yet, this book has very little to do with academy, or history for that matter. Instead, it's an iteration over anecdotes which he uses to create fridge-magnet poetry. The more one knows about the topic he covers, the more painful and frustrating it becomes to read. The section on genetic programming and computer virus (chapter 20; "Another life") is case in point, where it seems the talking points are taken from a Dan Brown or Michael Crichton novel.
There is little else to say about the facts or history covered in the book. None of it can be trusted, and untangling Harari's poetic babbling from actual facts will take hours of research for each chapter. As a list of discussion topics, it can work, as long as the problem with the facts and references are clear.
Unfortunate and potentially harmful
If Harari and his work had stayed fringe and unknown, it would have been a case of "nothing to see here, move along". However, through TED talks and clever marketing, he has gained a world-wide following; the book is translated to some thirty languages and is popular everywhere. That is very unfortunate, and potentially harmful.
In today's political climate, dealing with facts have become a fluid process, where anybody can declare something they disagree with as "fake news", and then present "alternative facts". US president Trump has made this type of political rhetoric mainstream, and it's already leaking across to Europe: When boots crushed skulls in the Catalonian attempt at an election, PM Mariano Rajoy simply declared the pictures of blood as fake news. When an election does not produce the desired result, we can simply blame it on Russian meddling (see Brexit), and so on.
In politics, lies have always been part of the game, while in science the standard have been facts and evidence. Although, there are exceptions, like Ron Hubbard's book "Dianetics" which is the basis for Scientology. Its rhetorical style is similar to Harari's, where the former tends to conclude "this can be scientifically proven", while the latter usually prefers "scholars agree". Neither support their claims with facts, evidence or references.
Popularizing this kind of pseudoscience is dangerous, and should not be taken lightly. Scientology has caused a lot of harm to many people, even if their organization is by now known to be predatory. By creating a following of more pseudoscience, Harari risks legitimizing both political and scientific opinion based "evidence". Throughout the "Sapiens" book, he declares his skepticisms towards almost any invention, discovery or change after the scientific revolution. In fact, in discussing happiness, Harari suggests that the hunter-gatherer or medieval farmer was happier than today's city dweller. We risk regressing back to a pre-Renaissance pre-science forum, where anybody can claim anything and get a following, no matter how ludicrous.
To some extent, that has already been going on for a while. Discussing the science and politics of global warming is already problematic, starting with agreeing on observable scientific facts. Fascists have used pseudoscience in an attempt to prove the Aryan race superior. Creationists, whom Harari unwittingly lends a bone, promote Intelligent Design to be taught alongside evolution and science. Yet all of the nonsense from these groups have not been a great problem because their voices have stayed fringe, and have easily been sidelined by hard facts and science.
Harari might not have intended to support these kind of fringe groups, but by legitimizing and popularizing pseudoscience and biased opinionated facts, he unintentionally gives credibility to those whom should not be given any. That is potentially harmful.