How We Got to Now: Six Innovations That Made the Modern World

by Steven Johnson

Dynasties fall, armies surge and retreat, the map of the world is redrawn. But the fall of Constantinople also triggered a seemingly minor event, lost in the midst of that vast reorganization of religious and geopolitical dominance and ignored by most historians of the time. A small community of glassmakers from Turkey sailed westward across the Mediterranean and settled in Venice, where they began practicing their trade in the prosperous new city growing out of the marshes on the shores of the Adriatic Sea.

The glassmakers had brought a new source of wealth to Venice, but they had also brought the less appealing habit of burning down the neighborhood.

in an effort to both retain the skills of the glassmakers and protect public safety, the city government sent the glassmakers into exile once again, only this time their journey was a short one—a mile across the Venetian Lagoon to the island of Murano. Unwittingly, the Venetian doges had created an innovation hub: by concentrating the glassmakers on a single island the size of a small city neighborhood, they triggered a surge of creativity, giving birth to an environment that possessed what economists call “information spillover.”

When the mixture cooled, it created an extraordinarily clear type of glass. Struck by its resemblance to the clearest rock crystals of quartz, Barovier called it cristallo. This was the birth of modern glass.

Most materials absorb the energy of light. On a subatomic level, electrons orbiting the atoms that made up the material effectively “swallow” the energy of the incoming photon of light, causing those electrons to gain energy. But electrons can gain or lose energy only in discrete steps, known as “quanta.” But the size of the steps varies from material to material. Silicon dioxide happens to have very large steps, which means that the energy from a single photon of light is not sufficient to bump up the electrons to the higher level of energy. Instead, the light passes through the material. (Most ultraviolet light, however, does have enough energy to be absorbed, which is why you can’t get a suntan through a glass window.)

Those early spectacles were called roidi da ogli, meaning “disks for the eyes.” Thanks to their resemblance to lentil beans—lentes in Latin—the disks themselves came to be called “lenses.”

The condition of “hyperopia”—farsightedness—was widely distributed through the population, but most people didn’t notice that they suffered from it, because they didn’t read.

People were farsighted; they just didn’t have any real reason to notice that they were farsighted.

What changed all of that, of course, was Gutenberg’s invention of the printing press in the 1440s.

You could fill a small library with the amount of historical scholarship that has been published documenting the impact of the printing press, the creation of what Marshall McLuhan famously called “the Gutenberg galaxy.” Literacy rates rose dramatically; subversive scientific and religious theories routed around the official channels of orthodox belief; popular amusements like the novel and printed pornography became commonplace. But Gutenberg’s great breakthrough had another, less celebrated effect: it made a massive number of people aware for the first time that they were farsighted.

What followed was one of the most extraordinary cases of the hummingbird effect in modern history. Gutenberg made printed books relatively cheap and portable, which triggered a rise in literacy, which exposed a flaw in the visual acuity of a sizable part of the population, which then created a new market for the manufacture of spectacles. Within a hundred years of Gutenberg’s invention, thousands of spectacle makers around Europe were thriving, and glasses became the first piece of advanced technology—since the invention of clothing in Neolithic times—that ordinary people would regularly wear on their bodies.

In 1590 in the small town of Middleburg in the Netherlands, father and son spectacle makers Hans and Zacharias Janssen experimented with lining up two lenses, not side by side like spectacles, but in line with each other, magnifying the objects they observed, thereby inventing the microscope.

Before long the microscope would reveal the invisible colonies of bacteria and viruses that both sustain and threaten human life, which in turn led to modern vaccines and antibiotics.

Twenty years after the invention of the microscope, a cluster of Dutch lensmakers, including Zacharias Janssen, more or less simultaneously invented the telescope.

Within a year, Galileo got word of this miraculous new device, and modified the Lippershey design to reach a magnification of ten times

This is the strange parallel history of Gutenberg’s invention. It has long been associated with the scientific revolution, for several reasons. Pamphlets and treatises from alleged heretics like Galileo could circulate ideas outside the censorious limits of the Church, ultimately undermining its authority; at the same time, the system of citation and reference that evolved in the decades after Gutenberg’s Bible became an essential tool in applying the scientific method. But Gutenberg’s creation advanced the march of science in another, less familiar way: it expanded possibilities of lens design, of glass itself.

The lens would go on to play a pivotal role in nineteenth- and twentieth-century media. It was first utilized by photographers to focus beams of light on specially treated paper that captured images, then by filmmakers to both record and subsequently project moving images for the first time. Starting in the 1940s, we began coating glass with phosphor and firing electrons at it, creating the hypnotic images of television. Within a few years, sociologists and media theorists were declaring that we had become a “society of the image,” the literate Gutenberg galaxy giving way to the blue glow of the TV screen and the Hollywood glamour shot.

By the middle of the next century, glass fibers, now wound together in a miraculous new material called fiberglass,

Scientists at Bell Labs then took fibers of this super-clear glass and shot laser beams down the length of them, fluctuating optical signals that corresponded to the zeroes and ones of binary code.

Using fiber-optic cables was vastly more efficient than sending electrical signals over copper cables, particularly for long distances:

Today, the backbone of the global Internet is built out of fiber-optic cables. Roughly ten distinct cables traverse the Atlantic Ocean, carrying almost all the voice and data communications between the continents.

IT’S EASY TO MAKE FUN of our penchant for taking selfies, but in fact there is a long and storied tradition behind that form of self-expression. Some of the most revered works of art from the Renaissance and early modernism are self-portraits; from Dürer to Leonardo, to Rembrandt, all the way to van Gogh with his bandaged ear, painters have been obsessed with capturing detailed and varied images of themselves on the canvas.

Rembrandt, for instance, painted around forty self-portraits over the course of his life. But the interesting thing about self-portraiture is that it effectively doesn’t exist as an artistic convention in Europe before 1400. People painted landscapes and royalty and religious scenes and a thousand other subjects. But they didn’t paint themselves.

Mirrors appeared so magical that they were quickly integrated into somewhat bizarre sacred rituals: During holy pilgrimages, it became common practice for well-off pilgrims to take a mirror with them. When visiting sacred relics, they would position themselves so that they could catch sight of the bones in the mirror’s reflection. Back home, they would then show off these mirrors to friends and relatives, boasting that they had brought back physical evidence of the relic by capturing the reflection of the sacred scene. Before turning to the printing press, Gutenberg had the start-up idea of manufacturing and selling small mirrors for departing pilgrims.

“Self-consciousness, introspection, mirror-conversation developed with the new object itself.” Social conventions as well as property rights and other legal customs began to revolve around the individual rather than the older, more collective units: the family, the tribe, the city, the kingdom. People began writing about their interior lives with far more scrutiny. Hamlet ruminated onstage; the novel emerged as a dominant form of storytelling, probing the inner mental lives of its characters with an unrivaled depth.

Entering a novel, particularly a first-person narrative, was a kind of conceptual parlor trick:

glass mirrors were among the first high-tech furnishings for the home, and once we began gazing into those mirrors, we began to see ourselves differently, in ways that encouraged the market systems that would then happily sell us more mirrors. It’s not that the mirror made the Renaissance, exactly, but that it got caught up in a positive feedback loop with other social forces, and its unusual capacity to reflect light strengthened those forces.

The mirror doesn’t “force” the Renaissance to happen; it “allows” it to happen.

Orienting laws around individuals led directly to an entire tradition of human rights and the prominence of individual liberty in legal codes.

The mirror helped invent the modern self, in some real but unquantifiable way.

create a universe that was exactly like ours, with only one tiny change: those electrons on the silicon atom don’t behave quite the same way. In this alternate universe, the electrons absorb light like most materials, instead of letting the photons pass through them.

On some fundamental level, it is impossible to imagine the last millennium without transparent glass. We can now manipulate carbon (in the form of that defining twentieth-century compound, plastic) into durable transparent materials that can do the job of glass, but that expertise is less than a century old. Tweak those silicon electrons, and you rob the last thousand years of windows, spectacles, lenses, test tubes, lightbulbs. (High-quality mirrors might have been independently invented using other reflective materials, though it would likely have taken a few centuries longer.)

world without glass would strike at the foundation of modern progress: the extended life spans that come from understanding the cell, the virus, and the bacterium; the genetic knowledge of what makes us human; the astronomer’s knowledge of our place in the universe. No material on Earth mattered more to those conceptual breakthroughs than glass.

But the need for silicon is a modern craving. The question is: Why did it take so long? Why were the extraordinary properties of this substance effectively ignored by nature, and why did those properties suddenly become essential to human society starting roughly a thousand years ago?

But surely one answer has to do with another technology: the furnace.

Despite a number of weather-related delays, the ice survived the journey in remarkably good shape. The problem proved to be one that Tudor had never contemplated. The residents of Martinique had no interest in his exotic frozen bounty. They simply had no idea what to do with it.

By his death in 1864, Tudor had amassed a fortune worth more than $200 million in today’s dollars.

There’s an additional, almost philosophical, curiosity to the ice business. Most of the trade in natural goods involves material that thrives in high-energy environments. Sugarcane, coffee, tea, cotton—all these staples of eighteenth- and nineteenth-century commerce were dependent on the blistering heat of tropical and subtropical climates; the fossil fuels that now circle the planet in tankers and pipelines are simply solar energy that was captured and stored by plants millions of years ago.

Americans are far more likely to enjoy ice with their beverages than Europeans, a distant legacy of Tudor’s ambition.)

In less than a century, ice had gone from a curiosity to a luxury to a necessity.

Ice-powered refrigeration changed the map of America, nowhere more so than in the transformation of Chicago.

But meat couldn’t make the journey without spoiling.

transporting entire cows was expensive, and the animals were often malnourished or even injured en route. Almost half would be inedible by the time they arrived in New York or in Boston.

1868, the pork magnate Benjamin Hutchinson built a new packing plant, featuring “cooling rooms packed with natural ice that allowed them to pack pork year-round, one of the principal innovations in the industry,”

It was the beginning of a revolution that would transform not only Chicago but the entire natural landscape of middle America.

the vast, shimmering grasslands replaced by industrial feedlots, creating, in Miller’s words, “a city-country [food] system that was the most powerful environmental force in transforming the American landscape since the Ice Age glaciers began their final retreat.”

The runaway growth of Chicago would have never been possible without the peculiar chemical properties of water: its capacity for storing and slowly releasing cold with only the slightest of human interventions.

This was the middle of the nineteenth century, after all, an era of coal-powered factories, with railroads and telegraph wires connecting massive cities. And yet the state of the art in cold technology was still entirely based on cutting chunks of frozen water out of a lake.

It’s not just a matter of a solitary genius coming up with a brilliant invention because he or she is smarter than everyone else. And that’s because ideas are fundamentally networks of other ideas.

The first thing that had to happen seems almost comical to us today: we had to discover that air was actually made of something,