Homo appeared roughly 2 million years ago in Africa and Homo sapiens roughly 200’000 years ago in East Africa. Harari divides his account of the last 70’000 years into four parts: The cognitive revolution (language), the agricultural revolution (about 10’000 years ago in today’s Turkey, Iran, Levant), the unification of humankind (through money, empire, and religion), and the scientific revolution. According to Harari, Sapiens developed more efficient strategies for cooperation than other species and in particular, Neanderthals (which sapiens eradicated around 30’000 years ago). The rest is history, i.e., evolutionary biology and cultural history.
On his website, Harari summarizes:
Homo sapiens rules the world because it is the only animal that can believe in things that exist purely in its own imagination, such as gods, states, money and human rights.
Starting from this provocative idea, Sapiens goes on to retell the history of our species from a completely fresh perspective. It explains that money is the most pluralistic system of mutual trust ever devised; that capitalism is the most successful religion ever invented; that the treatment of animals in modern agriculture is probably the worst crime in history; and that even though we are far more powerful than our ancient ancestors, we aren’t much happier.
According to Harari, the agricultural revolution fostered population growth but made life harsher for most humans (due to less varied diet, harder work, infectious diseases)—and for the animals that Sapiens domesticated; religion, empires, money and trade fostered globalization and unification; the scientific revolution arose from Europeans’ admission of ignorance, and it was intertwined with imperialism and capitalism; whether humankind has become happier over time is unknown but doubtful; and we may soon confront a singularity:
Physicists define the Big Bang as a singularity. It is a point at which all the known laws of nature did not exist. Time too did not exist. It is thus meaningless to say that anything existed `before’ the Big Bang. We may be fast approaching a new singularity, when all the concepts that give meaning to our world—me, you, men, women, love and hate—will become irrelevant. Anything happening beyond that point is meaningless to us (p. 461 in the Vintage 2015 edition).
- Settlement of Australia (“The Flood”), America, New Zealand: 45’000, 16’000, 800 years ago. Each settlement was associated with mass extinction of species.
- “[F]iction has enabled us not merely to imagine things, but to do so collectively” (p. 27). “Ever since the Cognitive Revolution Homo sapiens has been able to revise its behaviour rapidly in accordance with changing needs. This opened a fast lane of cultural evolution, bypassing the traffic jams of genetic evolution.” (p. 36).
- “The Agricultural Revolution was history’s greatest fraud. … These plants domesticated Homo sapiens, rather than vice versa” (p. 90). The revolution bred worries about the future. Food surpluses brought rulers and elites, palaces and temples, politics, wars, art and philosophy (p. 114). One `imagined order’ with three classes and two genders—the Code of Hammurabi—dates from 1’776 B.C. (p. 117). Writing, archiving, cataloguing (invented by Sumerians around 3’500 B.C.) preserves information about imagined social order; this is critical because the information is not preserved in DNA. Script undermined holistic thought. Hindus invented `Arab’ numerals around 800 AD (pp. 137–146).
- Cognitive dissonance, contradictory beliefs are necessary to maintain any human culture (p. 184). Over the last 10’000 years, thousands of `human worlds’ have collapsed to a single one (p. 186). Three universal (imagined) orders: Money, empire, religion (p. 191). “Money is the most universal and most efficient system of mutual trust ever devised” (p. 201). Empires are stable, inclusive, not that bad (p. 219). Religious norms are founded on a belief in a superhuman order (p. 234). “Much of ancient mythology is in fact a legal contract in which humans promise everlasting devotion to the gods in exchange for mastery over plants and animals” (p. 236). Polytheist and animist religions recognize a supreme power in the background, devoid of biases and interests (p. 238). Humanist religions worship Homo sapiens. Liberal humanism believes in the humanity of the individual. Socialist humanism believes in the humanity of the collective. (Both build on Christian tradition). Evolutionary humanism (e.g., Nazism) believes that humankind can evolve or degenerate (pp. 256–263).
- Science started from the admission of ignorance; observation and math; and the acquisition of new powers (p. 279). Social stability requires that certain `scientific results’ are a dogma or that basic truths are non-scientific (p. 282). With the capitalist system and the industrial revolution, science, industry and military technology intertwined (p. 294). “[S]cientific research can flourish only in alliance with some religion or ideology. The ideology justifies the costs of the research” (p. 305). Science and empire supported each other (ch. 15, 16). The scientific revolution and the idea of progress fostered credit; this reinforced each other (p. 346). The industrial revolution has been a revolution in energy conversion (p. 379) and it was a second agricultural revolution (p. 382). Animal suffering, consumerism (ch. 17). The national time (p. 396). State and market replace family and local community (p. 398). “The state and the market are the mother and the father of the individual” (p. 402). “The nation is the imagined community of the state” (p. 406). The world is safer than ever, and war does not pay any more. Have humans become happier? Answer 1: “Lasting happiness comes only from serotonin, dopamine and oxytocin” (p. 436). Answer 2: Meaning. But “[p]erhaps happiness is synchronising one’s personal delusions of meaning with the prevailing collective delusions” (p. 438). Answer 3: Feelings are not to be trusted; of key import is whether people know the truth about themselves (p. 443). Intelligent design and extreme inequality (ch. 20).
Wikipedia points to critical scholarly reception.