The book posits that humans are powerful because we can tell stories.
If there's one major takeaway from the book, it's that humans became the dominant species we are today because of our ability to create myths and tell stories.
We were once limited by a supposed law of nature that makes it nearly impossible to organize a group of more than 150 people, a limit known to anthropologists as Dunbar's number. Above that number, the theory goes, humans have a hard time forming close relationships and trusting others.
But if we create myths and tell stories, we can form connections with people outside of our core group because we have a shared interest or knowledge in something, and trust can be formed.
No other animals can band together by the millions because no other animals can tell stories.
This is how nation-states were built and world religions were formed, according to Harari. It is also why people believe in economies and a paper money system.
We tell stories, give value to things, and fight (often literally) to keep those traditions alive.
That same storytelling superpower that allowed for the creation of religions and economic systems, also helped businesses, as we know them today, to form into massive and lasting operations.
Harari used the example of the French auto-giant Peugeot to illustrate his point.
If suddenly every Peugeot employee died and every car vanished from the streets, the company would still exist, Harari posits. That's because the company is not simply its people or its product — the idea of Peugeot as a business has been collectively agreed upon by society.
We may have been better off before the Industrial Revolution, Harari writes.
In the book, Harari makes contrarian claims throughout.
How can we think of early humans as "tree-huggers" if they were killing big game animals and causing mass extinctions like the Dodo? And religion may be just another method humans used for organizing society, similar to politics or economics, he writes.
But maybe the most contrarian point raised in "Sapiens" was that the Agricultural Revolution may have been a bad idea.
Farming increased the amount of available food, increased the human population, and allowed people to specialize in a wide variety of trades. But, he argues, it's questionable whether or not it was actually worth it.
Having surplus food may have allowed us to create politics, art, and philosophy — but it also led to war and a widening class system. Also, peasants working before our modern era faced longer hours and more exposure to disease than our early hunter-gatherer descendants.
Harari makes the case that the human species may have been better off as foragers before farming changed everything.
Human happiness may just be a matter of expectations, the book suggests.
Harari's 200,000-year history of humankind comes down to the main question of whether our progression as a species has made us any happier in the end.
Back to the hunter-gather example — foragers worked fewer hours and lived in less isolation, spending more time with close friends and family.
So, were early humans actually happier than we are today?
Harari thinks that just because human capabilities have increased, we shouldn't necessarily be happier as a species.
Instead, he writes that “happiness does not really depend on objective conditions of wealth, health or even community. Rather, it depends on the correlation between objective conditions and subjective expectations.”
The concept is perhaps best illustrated by Harari's allegory of two twins — one who experienced permanent damage to his leg in a car crash, while on the same day, his twin brother won the lottery. Two years later, he writes, both brothers will have the same levels of happiness they each had on that fateful day, for better or for worse.
That's because with those dramatic events, their expectations for life were reset, and happiness, according to Harari, is a function of those expectations.
Overall, Sapiens was a nice break from reading about the tech world, and perhaps that's why everyone in Silicon Valley is so obsessed.
Overall, "Sapiens" was a welcomed break from reading startup and strategy books recommended by business moguls and chatty VCs on Twitter.
It's not often in the tech world that we stop to think about why babies can't fend for themselves (Harari says because we are born prematurely because women's hips started narrowing after humans started walking upright) or why humans binge-eat (he says because our forager forefathers were taught to eat as much as possible, whenever possible).
I also never really stopped to consider why so many of us choose to wear denim jeans (Harari writes that it's society's way of silently promoting equality, since they're worn by rich and poor alike).
Reading "Sapiens" felt like I was back in a college anthropology class, questioning the fundamentals of global society.
Why do I give value to this paper dollar in my pocket? What is progress? What is happiness?
Perhaps that's why the tech community loved "Sapiens" so much — because it's a break from tech itself, while presenting theories and thought experiments that are applicable to, well, all of humankind.