Homo Deus: A Brief History of Tomorrow
Yuval Noah Harari (HarperCollins, 2017)
By Nathan Curland
Homo sapiens have, in the last few millennia, filled every corner of the planet and—in less than 100 years—have for all practical purposes conquered plague, famine, and war. How did this happen?
What sets Homo sapiens apart from other species? What is the mind? Or consciousness? Do we have free will or are we just algorithms? What, how, and why is religion? Do Homo sapiens have a future? Or will they be superseded by another species?
These are the big questions that Yuval Harari tackles in the sweeping, thought-provoking, and entertaining book Homo Deus: A Brief History of Tomorrow. Harari is a historian who studied at Oxford and now lectures at the Hebrew University of Jerusalem, but clearly understands much more than history. He has studied the sciences and is up to date on the latest advances in biology, neuroscience, and artificial intelligence (that is, as of 2016, as he is quick to point out!).
In an unusually long, 70-page introduction, “The New Human Agenda,” Harari makes a compelling argument for humanity’s successes—for example, war casualties are at their lowest point in history and though many people still suffer from poverty and hunger, few (outside of war zones) die of starvation, as in the period before agricultural industrialization.
But Homo sapiens are never satisfied. Success is an emotionally fleeting sensation and thus breeds ambition, prompting humanity to find new challenges. Harari asserts that the new challenges are immortality, happiness, and divinity. “We will aim to upgrade humans into gods, and turn Homo sapiens into Homo deus.”
His introduction also summarizes the rise of gods. For tens of thousands of years our ancestors were hunter-gatherers and lived in harmony with nature. To make sense of the unexpected events of their limited world, they invented spirits that inhabited various aspects of their lives, for example animals, rocks, or trees.
The Agricultural Revolution caused a massive shift, resulting in surplus food stuffs, specialization, and trade. This was accompanied by large-scale problems such as plague, war, and dependence on weather and climate. Spirit explanations just didn’t cut it and thus gods were invented. The Scientific Revolution did away with humanity's reliance on gods to intervene as it began to discover what actually caused uncontrollable events and developed methods to mitigate them.
Humans rule through cooperation, imagination
Part I deals with how Homo sapiens “Conquered the World.” Here Harari does away with many of the common beliefs of the superiority of humans over other life forms. An organism is nothing more than an algorithm, he asserts, albeit one controlled by genes, hormones, and experience.
He shows through concrete examples that other animals have sentience that is not that different from ours and that the moral authority we have over creation is a myth. He notes that evolution was a devastating blow to the religious idea of a “soul” since the concept of an indivisible, complex ethereal being is inconsistent with the gradual step-by-step process of natural selection.
In the end, he builds a strong case that the reason humans rule the world is because they have developed the ability to cooperate in large numbers. This was fueled by the development of written language and exploded with the invention of the printing press. However, these practical physical inventions were not sufficient. To be able to motivate masses of humanity, Homo sapiens needed to “weave an intersubjective web of meaning”: laws, forces, places, entities like corporations and churches, and so on, that exist in the common imagination.
In Part II, “Homo Sapiens Give Meaning to the World,” Harari shows how our ability to tell stories on a grand scale resulted in the creation of a myriad of institutions. Whereas animals live a dual reality—objective and subjective—humans exist in a triple reality that also includes fiction, or imagination. History revolves around a web of stories.
One chapter discusses “The Modern Covenant.” This is the “deal” that we have all been born into: humans agree to give up meaning in exchange for power. This leads to the modern myths of sustainable growth and the continuing ability of human engineering and science to overcome the limitations of our planet’s ecosystem and handle our population explosion.
But what about meaning? If there is no meaning in the universe, how do we give meaning to our lives?
The three branches of humanism
This leads to the most controversial chapter for Humanists, “The Humanist Revolution.” Harari uses the word “humanism” not in the sense that the modern Humanist movement does, as an ethical philosophy. In fact, nowhere does he acknowledge that such a movement exists.
For him, humanism is a revolutionary creed “that conquered the world during the last few centuries. The humanist religion worships humanity and expects humanity to play the part (of) God.” The “primary commandment humanism has given us: create meaning for a meaningless world.” (By contrast, Harari defines religion as “believing in some system of moral laws that wasn’t invented by humans,” which can include laws invented by gods or “natural” laws.)
With such a broad definition, Harari can divide humanism into three branches: The first is “liberal humanism,” which grew out of the Enlightenment and “holds that each human being is a unique individual possessing a distinct inner voice” and unique experiences and ought to be given as much freedom as possible. The second is “socialist humanism,” developed in the 19th century, which includes a plethora of socialist and communist movements. The third is “evolutionary humanism,” which includes social Darwinist movements such as Nazism.
These movements have given humanity meaning in the modern world. At least for now, Harari says, liberal humanism has won over the other two options due to the successful rise of industrialization, capitalism, and globalization.
In Part III, “Homo Sapiens Loses Control,” Harari describes how recent breakthroughs in science, especially neuroscience and biology, have shown how little free will humans actually have and how artificial intelligence is making it possible for machines to take over most (and eventually all?) of the jobs currently being done by humans. (After all, if humans are just algorithmic machines, why are they needed at all?) This combination will eventually make Homo sapiens superfluous.
A new species?
To survive, humanity will have to go to another level, either via genetics, machine-human integration, or some combination. Harari predicts that this is already happening and by the end of this century humans will exist who can potentially live forever. Furthermore, these humans will be a new species (and form a new elite) and will be to Homo sapiens as we are to Neanderthals.
This section is filled with details of the latest scientific knowledge and, of course, is the most speculative. This Harari readily acknowledges and notes that it is up to Homo sapiens to decide which path it will follow. (Note: I’m not sure how this happens if we have no free will! Perhaps Harari was just trying to soften the message.)
In this short review, I can only briefly touch on this volume’s key insights. Harari paints his picture of the past and future using a rich palette of history, metaphor, scientific and psychological insight, stories, concrete examples, and a touch of speculation.
But Homo Deus, despite its 400 pages, is an easy read. Harari’s style is engaging and in every chapter you will find ideas that challenge your knowledge and understanding of the world, ideas that intrigue you, ideas that disturb you, ideas that anger you, and ideas that make you smile. This book will make you think. Read it.
(Note: In the June/July 2017 issue of Free Inquiry, editor Tom Flynn used his editorial column, which he titled “Smearing Humanism,” to take Harari to task for the definition of “humanism” that Harari first used in his 2011 best-seller Sapiens. This is perfectly understandable for someone who spent his entire career promoting and defending modern organized Humanism. It is unfortunate, however, that this blinds him to the contributions and insights that Harari brings to the intellectual table.)