The library of Alexandria and the loss of knowledge

Note (Oct. 2023). This article is about the library’s weirdly overblown reputation. I recommend also taking a look at this piece from 2022, which talks about how it got that reputation.

Myth: the burning of the library of Alexandria was "the most destructive fire in the history of human culture".

Alexandria was the chief city of Hellenistic and Roman Egypt, and the most important cultural powerhouse of the ancient Mediterranean. The quotation above comes from this History Channel clip about its famous library, or rather libraries.

The narrator goes on (at the 1 min. 39 sec. mark):

In the battle that followed, Caesar ordered his soldiers to burn the Egyptian fleets lying in the harbour. The fire quickly spread from the waterfront to the great library. The flames consumed a large part of the library's collection, marking the single greatest loss of knowledge in history.

Some historians speculate that the fire set civilisation back by a thousand years. Who knows, if the great library of Alexandria hadn't burned, Columbus may not have sailed to the New World. He might have gone to the moon!

Recently a new library was built in Alexandria, but it can never replace the ancient collection burnt in the fire. It contained rare manuscripts, the comedies of Aristotle, and more than 200 plays by Aeschylus and Euripides — classic works forever lost.

Doctor sitting reading by an armarium holding books early 4th cent. CE; Met. Mus. of Art, New York)

This snippet ranges from absurd to outright false. (Let's do the easy bits right away: Aristotle didn't write comedies, and Aeschylus and Euripides wrote a combined total of about 170 plays.) The only bit that has any basis in reality is the first line, about Caesar burning the Ptolemaic fleet. Everything else is untrue, without any room for doubt on the point.

It's not like the History Channel is conveying an isolated opinion, by the way. It is really widely believed. Here's a full-length documentary that makes similar claims; the Wikipedia article on the subject refers to "the incalculable loss of ancient works"; Joel Levy's 2006 book Lost Histories calls it "the day that history lost its memory"; online forums frequently get questions about just how big a disaster it was.

Important point: I'm not talking today about the historical circumstances of the library's destruction. There certainly was a major fire in 47 BCE, and there may have been other important moments of destruction in later centuries. We're not here to pin down when it disappeared, or who's to blame: this is about the historical significance of the library's loss.

Several kinds of misconception feed into this myth.

1. Misconceptions about the role of libraries in the ancient world.
2. Misconceptions about what kinds of books the Alexandrian library actually held.
3. Misconceptions about the actual causes for the loss of texts from antiquity.

1. The role of libraries

If the loss of the library was "the single greatest loss of knowledge" in history, that would mean the books destroyed were the only existing copies of those books.

Suppose — heaven forfend — that the British Library burned down tomorrow, or the Library of Congress. What kind of a loss would it be? In cultural terms, and purely in monetary terms, it would be catastrophic: millions of manuscripts, autographs, and rare and unique items would be lost, and the cost of replacing the printed collection would be vast.

But barely a scrap of actual knowledge would be lost. Ismail Kadare's novels would survive. The Thirty Years War would not be forgotten. Aeroplanes and computers would not become treasured relics, never to be recreated.

This is because there are lots and lots and lots of repositories of information in the world. And exactly the same was true in Greco-Roman antiquity. There were hundreds of libraries of Greek and Latin texts dotted around the Mediterranean. Alexandria was the biggest, but it was just one fish in a sea of libraries. There were also important centres at Pergamon, Athens, Rome, Constantinople, and many important private collections. Roman aristocrats founded many libraries in the early Principate; clubs and gymnasia in Greece were also centres of learning, with their own libraries, and we have inscriptions cataloguing regular deposits of books in their collections. Caesar's fire did not stop Athenaeus and Julius Africanus from being profoundly well-read more than two centuries later, and the likes of Pliny the Elder and Pausanias did their research privately or in Athens, not in Alexandria.

A fanciful depiction of the library in the Serapeion at Alexandria (Agora, 2009). (Who's in charge of this mess? The scrolls don't even have labels!)

The book trade thrived and had mass audiences. The literacy rate was higher than many modern people would naively expect: nowhere near modern First World levels, to be sure, but there was a big market for things like popular romances, basic reference books, and how-to manuals. Literacy was certainly not limited to a small elite class: almost anyone could scrawl graffiti on a wall without much education. Cicero refers to the publishing business on a scale that, for the time, we may as well consider industrial (Q.fr. 3.6.6; Att. 12.6a). Books travelled from city to city easily: Pliny the Younger is delighted to hear that his own books were on sale at shops in Lyon (Letters 9.11.2). Book prices in 1st century CE Rome ranged from 6 sestertii for a cheap knockoff (Martial 1.66; one or two days' labourer's wage) to 5 denarii for a deluxe edition (Martial 1.117; = 30 sestertii). The amounts don't translate well into modern terms, but they're comparable to the prices of university textbooks: not chicken feed, but certainly not just for the elite either. To save costs further, publishers could recycle used papyrus (Catullus 22.5), or customers could commission copies made on the back of something else.

This last point is directly tied to one important function of ancient libraries. As well as being reading rooms, they were also scribal centres that bypassed the book trade. People could commission a scribe to go and make a copy of a book, and it seems this was a pretty economical thing to do. (Remember copyright is irrelevant in a society where reproduction is labour-intensive.) A beautiful example is the sole surviving copy of Aristotle's Constitution of the Athenians. An estate owner living near Hermopolis, Egypt, recycled four scrolls of his farm and business records by commissioning scribes to make a copy of some fairly high-powered intellectual works on the back, including Aristotle's book. (It's very unlikely that the copying was done at Alexandria, about 200 km away.) The economics of the situation are telling: the owner was willing to hire professional scribes, but not to pay for clean papyrus. In other words, scribes were cheap.

It is unlikely that more than a handful of texts of any consequence were lost in the fire of 47 BCE, for the simple reason that anything important certainly existed in many copies, in libraries and private collections, all over the Mediterranean.

2. The books in the library

In the popular imagination, the library held all manner of arcane knowledge lost in the mists of time — Babylonian mathematical treatises, dictionaries of Linear A, diplomatic correspondence between Egypt and Atlantis, the history of Göbekli Tepe, that kind of thing.

Illustrated edition of a poem about Herakles, probably for a popular audience: Herakles' fight with the Nemean lion (P.Oxy. 2331, 3rd century)

In reality it was not a repository of records left by the Pharaohs of the Old Kingdom. It was a Greek library, of Greek texts, for Greek people, founded around 300 BCE. One late source tells us that there were accessions of Egyptian, Chaldaean, and Roman books, but they were invariably translated into Greek (Syncellus, Chronographia 516,6-10). We don't know if the originals would have been preserved too; it doesn't seem likely that they were prized.

We have a very good idea of the kinds of things that were in the library. This is because surviving books routinely cite and discuss other books, including ones that have been lost. Many important pieces of modern research revolve around gathering together the fragments that we obtain this way: the most important such collection, the Fragmente der griechischen Historiker, lists over 1000 lost authors — and that's just in the genres of history and geography. In some cases we know a huge amount about these books; in other cases we know only titles. But it's more than enough to tell us that what we are missing is, essentially, pretty similar to what survived via the mediaeval manuscript tradition.

The thing that we're really missing out on is the colossal book-writing spree that Greek thinkers all round the Mediterranean went on in the late 4th to 1st centuries BCE: we have comparatively few intact books from that period — we have Aristotle, Euclid, and Dionysius of Halicarnassus, but we're missing out on the likes of Eratosthenes, Hipparchus, and Crates.

3. How ancient texts actually got lost

The destruction of a library is a terrible thing, but it's a drop in the ocean. The disappearance of Greco-Roman texts is a story about culture and economics, not a timeline of specific events. Left to themselves, books vanish over time without any need for someone stepping in to destroy them. Poor storage, poor longevity in the materials, environmental factors, and human agency all hasten that natural decay, but that decay will happen anyway. Over a thousand years, that's plenty to ensure the demise of nearly every book in existence.

Sure, it would be nice if the library of Alexandria had survived to the present day. But that means positing a miracle. No ancient library has survived to the present. Even if the Alexandrian library had survived the fires, eventually it would have gone the same way as the Palatine library in Rome — which suffered its own series of catastrophic fires (the History Channel never talks about those) — and the libraries of Pergamon, Tralles, Athens, and so on. Aristotle's Constitution of the Athenians, mentioned above, is a truly extraordinary case: only a handful of texts have survived by being preserved on an intact ancient papyrus.

Codex and scroll (Pompeii, before 79 CE): left, woman with note-taking codex (wax on wood); right, man with commercial scroll (with titulus)

Books survive if many different people ensure that they're copied. And the people of the past who did that copying weren't operating with any top-down, organised plan; they weren't members of a worldwide Book Preservation Society. They were independent institutions and individuals living in many different places and many different centuries, and their efforts just happen to have the fortunate combined effect that many texts have survived to the present.

Texts were disappearing long before Rome fell. The 2nd century CE is when we really start to notice extant sources treating old texts as things they haven't personally read — they only have second- or third-hand information. In other words, that's when texts start vanishing en masse. J. O. Ward, cited above, points out that many oratorical speeches from Cicero's time were already obscure in Tacitus' time. We have no evidence of any of the Epic Cycle surviving beyond the 2nd century. (Some of them did survive that long: so however they were lost, it had nothing to do with events in Alexandria.) Not a single ancient writer ever cites book 2 of Aristotle's Poetics, other than Aristotle himself: it was never as popular as the similar material in his On poets (also lost), which was intended for a wider audience, and about which we hear a great deal. Poetics book 2 may well have disappeared within a century of being written.

The 2nd-3rd centuries were also the time of a massive technical migration: from scroll to codex. ('Codex' is the word for a modern-style book, with pages sewn together at the spine.) The very biggest hurdle for the survival of books is nothing to do with libraries burning, or fictional stories about religious zealots destroying pagan books. It's about a format shift.

We first begin to hear about commercial use of codices by ancient booksellers in the 1st century CE poet Martial, who is impressed after seeing a codex edition of Ovid's Metamorphoses with the entire text in one volume (Epigrams 14.192):

haec tibi multiplici quae structa est massa tabella,
carmina Nasonis quinque decemque gerit.

Look at this bulk! It's built out of many­-layered leaves,
and holds fifteen books of Naso's poem.

Lionel Casson's Libraries in the Ancient World (2001), pp. 127-8, reports the following proportions in Egyptian papyrus finds:

	Scroll	Codex
1st-2nd centuries CE	98.5%	1.5%
ca. 300 CE	50%	50%
ca. 400 CE	20%	80%
ca. 500 CE	10%	90%

An armarium for codices: the real reason for the loss of Greco-Roman texts. (Codex Amiatinus, early 8th cent. CE)

A format shift doesn't only attach an extra cost to the survival of any text, it also attaches a time­-limit. If the storage units in your library are armaria for codices, scrolls that haven't been transferred by the deadline will simply not get stored in the library. In addition, ancient and mediaeval codices were normally stored flat on their backs — not on end, as in modern bookshelves — and they couldn't be piled high, if they could be piled at all. So even though a codex could hold a lot more text than a scroll, codices took up more space for the same amount of text!

Scrolls were effectively a self-destruct timer. A book published in scroll form might survive a century or three after 300 CE; but if it hadn't been copied into a codex by that date, the text was basically doomed.

Wars and fires don't help of course, but those are pretty minor things in comparison to a format shift that affected all books.

So don't lament for the library of Alexandria: celebrate it for what it was. It's an important chapter in the story of the development of knowledge. But in the story of the loss of knowledge, it barely warrants even a footnote.

Some other popular sources do a perfectly decent job with this topic: Carl Sagan's TV series Cosmos is a bit notorious for being unreliable on history, but it's on relatively steady ground here (1980; episode 1, "The shores of the cosmic ocean") —

Each of those million volumes which once existed in this library were handwritten on papyrus manuscript scrolls. What happened to all those books?

The classical civilisation that created them disintegrated. The library itself was destroyed. Only a small fraction of the works survived. And as for the rest, we're left only with pathetic scattered fragments.

This could be a lot worse. It's not flawless: elsewhere Sagan implies that figures like Aristarchus of Samos and Archimedes had something to do with Alexandria, when there's no evidence they ever even visited the city. But he's absolutely right to emphasise the demise of the civilisations that created libraries, or rather their governments — the Ptolemies in Alexandria, the Attalids in Pergamon — and not any single moment of destruction. If Caesar's Alexandrian War caused a loss of knowledge at all, it wasn't because of a fire: it was because he effectively ended the Ptolemaic dynasty, which had been supporting the library's operations for 250 years. If the Ptolemies had still reigned in 300 CE, it's likely that more work would have been put into preservation efforts.