I've written a bit on Sapiens here, and link to several other threads and resources in that comment. To summarize, Harari radically overstates the importance of the "Cognitive Revolution" (a supposed leap in human intelligence some thousands of years after H. sapiens appeared which a fair portion, if not a majority, of bioanthropologists don't believe even happened), mistakes the history of Western Civilization for the history of our species, ignores the extent to which cooperation has driven primate evolution, seems to be writing more to satisfy his own curiosity as layman than to approach any of the material with the critical eye of an expert. As an anthropologist, I take the most issue with his continual use of words like "myth" or "fiction" to describe any and all sort of abstract thought. While Harari would have you believe that it's fascinating and important that so many things in our world are "made up" and "don't exist," that's just the basic underlying concept of "culture" that has been the foundation of social science for one hundred years.