Book SummaryNexus, by Yuval Noah Harari

1-Page Summary1-Page Book Summary of Nexus

In Nexus (2024), Yuval Noah Harari cuts through the typical artificial intelligence (AI) doomsday scenarios to identify a more subtle but potentially more devastating threat: AI's growing power to control how humans share and consume information. While others warn about AI taking our jobs or turning hostile, Harari argues that AI's true danger lies in its ability to manipulate the stories we tell—the very foundation of human civilization.

Drawing on historical examples from the printing press to social media algorithms, Harari demonstrates how changes in information technology have repeatedly transformed society, sometimes with catastrophic consequences. He argues that AI represents the most significant transformation yet, as it may soon surpass humans at our most distinctive capability: creating and sharing the stories that give our world meaning. At the heart of Harari's concern is a profound shift in who controls our information: For the first time in human history, AI—not humans—increasingly determines what stories we encounter and share.

Harari is a historian and philosopher with a Ph.D. from the University of Oxford. His other books include...

Nexus Summary What Is Information?

We’ll begin with Harari’s definition of information. He explains that information is knowledge that connects and organizes people: It's the stories, beliefs, and ideas that can transform a random assortment of individuals into a cohesive social group united behind a common cause. Importantly, these stories don't need to be true to be powerful—in fact, most information isn't objectively true at all.

Harari explains that the disconnect between information and truth can actually be beneficial: The stories we share can create social bonds, instill hope, encourage optimism, and inspire people to work together to achieve great things. But Harari's key insight is that we avidly consume and share information based on how compelling the story is, not on whether it reflects reality. And some of the most attention-grabbing, emotionally moving stories are demonstrably untrue. (We’ll explore this insight further later on.)

(Shortform note: How long have humans been able to share information with each other? Perhaps for a shorter amount of time than anthropologists have traditionally assumed. While [two-million-year-old stone...

Nexus Summary How Does Information Move Through Society?

Throughout human history, information and power have moved together. Harari explains that each time a new technology has made information more readily accessible, it has fundamentally reshaped society. First, written language, inscribed on stone or clay tablets, enabled our ancestors to keep records and codify their rules of government. Next, books produced by hand—on tablets, scrolls, parchment, and papyrus—enabled large bodies of knowledge on law, history, religion, and other topics to be shared in writing and over time and distance, instead of just orally and person-to-person. Then, the printing press enabled the widespread dissemination of information and therefore the democratization of knowledge.

(Shortform note: As Harari notes, the ways in which technology makes information more accessible have always been tied to shifts in power: The advent of written language helped governments enforce laws, hand-produced books allowed experts to [curate and disseminate...

Nexus Summary How Is AI Changing Our Relationship With Information?

Harari explains that we’re living in an “information age,” where knowledge is proliferating, access to information is democratized, and everyone with a smartphone and internet access can share their ideas with the world. As we develop tools like AI, we’re increasing the speed at which stories can be shared. When you consider what makes a human society free, equitable, or democratic, having more information sounds like an inherent good. (An especially American expression of this is the idea, written down by Thomas Jefferson, is that a well-informed electorate plays a vital role in keeping authorities in check and guarding against tyranny.)

But, counter to that notion, Harari worries that recent developments that make information more accessible to us threaten to tip the balance toward the most extreme, least truthful, and most divisive messages.

(Shortform note: Even before AI entered the scene, some experts questioned whether our increasing access to information is an inherent good. Early internet idealists envisioned a digital utopia where open access to knowledge would lead to more informed, rational...

Shortform Exercise: Analyze Your Information Diet

Our information consumption habits shape how we understand the world. Use these questions to examine how AI might be influencing your perspective through the content you consume.

Think about where you get most of your news and information. List your top three sources (social media platforms, news sites, and so on). For each one, does an AI algorithm determine what content you see?