According to the myth, handsome Narcissus once gazed at himself in a pool of water and fell in love with his own reflection, a self-obsession that would ultimately doom him.

While we can be grateful to this cautionary tale for inspiring the term narcissism, it seems a tad unfair for us to fault one Greek youth for being fascinated by his own appearance. After all, humans have been obsessed with their reflections for millennia, and that obsession would trigger the development of one of the greatest inventions in the history of our species: the humble mirror.

Like Narcissus, early humans probably first became acquainted with their reflections by seeing them in a pool of water. Although they likely didn’t use this discovery for grooming or self-introspection, at some point they would have understood that they were looking at themselves.

This is no trivial ability: Being able to identify your reflection as you and not some other creature is uncommon in nature — sure, some animals like elephants, dolphins and other primates can pass the so-called mirror test, but it’s a pretty short list. And among humans, recognizing your reflection as your reflection — in short, having a basic sense of self — is a foundational aspect of cognition and an important part of human development.

From a modern perspective, the invention of the mirror must seem like something that was inevitable, almost pre-ordained. But like so many other inventions, developing the modern mirror as we know it was a long, imperfect and sometimes expensive process. Let’s pause now to reflect on the history of the mirror and what its evolution has meant for our evolution.

Early Mirrors From Obsidian Rock

Humans have known how to make glass in one form or another for about 4,000 years, but we’ve known how to polish naturally occurring glass for a lot longer. The earliest known mirrors were just that: polished glass — specifically, the volcanic glass known as obsidian. Discovered in burial sites at Catalhoyuk, one of the oldest cities in the world (located in what is now modern-day Turkey), these hand-sized objects date to around 6000 B.C.

These proto-mirrors were highly polished and shaped on one side, revealing not only a surprisingly reflective surface, but also an impressive level of skill and technology for people of that time period.

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As humans got better at working with metal, several civilizations came up with the idea of hammering bronze or copper flat, then polishing the surface until it was reflective — or at least as reflective as polished metal could be.

Some of the oldest surviving examples include bronze mirrors made in Egypt around 2900 B.C., although metal mirrors of almost the same vintage have been found in China, India and elsewhere. Greeks and Romans loved their mirrors, too, and the wealthy could afford to have theirs plated in silver. 

When Were Mirrors Invented?

By the 1st century A.D., humans had apparently advanced the art of glassmaking and glassblowing sufficiently that it finally occurred to someone to create a really good reflective surface by coating the back of a piece of glass with lead or even gold.

Roman writer and naturalist Pliny the Elder recorded that such mirrors were being made at that time, and they exhibited highly reflective surfaces. However, no archaeological evidence of early glass mirrors would turn up for another few hundred years. Even then, the examples found from that era were probably used as jewelry since they likely would have been too small to gaze at one’s own reflection or use for grooming.

While the art of quality glassmaking waned as the Roman Empire declined, it would enjoy a resurgence. Around the late 13th century, Italy — specifically Venice and the island of Murano — would become renowned for the quality of its glass. By the 1500s, Venetian mirrors were the gold standard of glass mirrors, coveted for both their size and quality, and desired throughout Europe and beyond by those who could afford such expensive luxuries (which at the time was mostly nobles and royalty).

Over time, fine glass mirrors did become somewhat more affordable, but were still costly and prized possessions for the middle or merchant classes that began to acquire them. Some manufacturers used an amalgam of tin and mercury which, while cheaper, were toxic and dangerous. But many examples survive and you can still find antique mercury mirrors selling at auction today. 

When Did Mirrors Become Widely Available?

It wasn’t until the 1830s that the modern, affordable mirror as most of us would know it finally appeared. It was in 1835 that a German chemist, Justus von Liebig, perfected a method of applying silver nitrate to glass which, through chemical means, was converted into a thin, reflective layer of silver.

This process resulted in a highly reflective surface that adhered well to glass, creating an effective, stylish, affordable mirror of almost any size. When you hear anyone talk about the process of “mirror silvering” today, it dates back to von Liebig’s innovation. But these days, silver really isn’t used in the making of mirrors — aluminum is the preferred metal. 

Why Do We Love Mirrors?

Today, mirrors are everywhere, no longer a showpiece or luxury item, but now a fixture to the point of obscurity. Aside from their many scientific, industrial and even mystical uses, we can find mirrors almost anywhere: in our bedrooms and bathrooms, our cars, our purses and even online, whenever we sign into a video chat and see ourselves reflected on-screen.

We take mirrors for granted and yet: Try to imagine a world where mirrors didn’t exist — or at least were not commonly available. It really wasn’t all that long ago that this was the case, when humans had no easy way to see ourselves reflected back at us.

Scientists and philosophers have devoted a surprising amount of time and thought to the power and influence of mirrors over the human psyche. And the overarching impression is that our civilization, and indeed our very existence, would be quite different if we didn’t have mirrors around.

As best-selling historian Ian Mortimer noted in his well-regarded book, Millennium: From Religion to Revolution: How Civilization Has Changed Over a Thousand Years, mirrors reshaped humanity’s idea of what it means to be an individual. “The very act of a person seeing himself in a mirror … encouraged him to think of himself in a different way. He began to see himself as unique,” Mortimer writes.

Let that sink in for a minute. Because before mirrors were widely available, Mortimer and others argue, we thought of ourselves as relatively insignificant individuals, mere component parts of a society, drones among the masses. But in redefining our personal sense of identity, mirrors both enabled and literally reflected a modern sensibility about humanity and individuality, one so ingrained in our species now that it would be hard to envision civilization today without it.

Think about that the next time you take a look in the mirror and ponder how far we’ve advanced because of what a simple looking glass could show us. Maybe Narcissus was right after all to be so fascinated by his own reflection.

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