This book certainly is the result of big thinking, and is a fascinating study of the history of humankind. He begins with the original hominids, mentioning Homo Erectus and the Neanderthals, and then on to Homo Sapiens.
The development of imagination by the Sapiens, the Cognitive Revolution, around 70,000 BCE, in his opinion was the first great division of the Sapiens from the other great apes. In 12,000 BCE, when the species developed agriculture, the Agricultural Revolution, was the next huge leap forward. This resulted in the unification of humankind, as Empires consolidated peoples into ever larger groups of political organizations. In 1500 CE, the Scientific Revolution began to replace the ideologies of blind faith with objective science, searching after reality.
Dr. Harari argues that the development of imagination allowes Homo Sapiens to cooperate in large numbers. The imagination allows them to believe in the fictions created in the human mind. Trade brought the necessary creation of money, which is a fiction based on mutual trust. Living in communities, as a result of agriculture and specialisation, brought the imaginative creations of the political, legal and religious ideologies that bind people together into cultures. These are all fictions, ideologies created in the human mind, and each culture has its own imaginative constructs.
The trend is for the interdependence of the human race, which is moving towards a World Empire. Dr. Harari argues that globalization in trade, money, and universal religions, is driving that process. The imaginative constructs of universal religions are inclusive of all humans, whether they follow any particular religion, or none at all.
Dr. Harari asks the big question as to whether humans are any happier in modern civilizations than were the ancient palaeolithic hunter gatherers? He suggests that a research study of happiness is overdue. He also points out the inhuman way animals have been treated by Homo sapiens over the ages. He considers those animals are not happier.
The book ends up with speculations as to where the human race is headed. Will we become super human beings?