Commas, semicolons and question marks are so commonplace it seems as if they were always there – but that’s not the case. Keith Houston explains their history.

As readers and writers, we’re intimately familiar with the dots, strokes and dashes that punctuate the written word. The comma, colon, semicolon and their siblings are integral parts of writing, pointing out grammatical structures and helping us transform letters into spoken words or mental images. We would be lost without them (or, at the very least, extremely confused), and yet the earliest readers and writers managed without it for thousands of years. What changed their minds?

In the 3rd Century BCE, in the Hellenic Egyptian city of Alexandria, a librarian named Aristophanes had had enough. He was chief of staff at the city’s famous library, home to hundreds of thousands of scrolls, which were all frustratingly time-consuming to read. For as long as anyone could remember, the Greeks had written their texts so that their letters ran together withnospacesorpunctuation and without any distinction between lowercase and capitals. It was up to the reader to pick their way through this unforgiving mass of letters to discover where each word or sentence ended and the next began.

In early Greece and Rome, persuasive speech was more important than written language

Yet the lack of punctuation and word spaces was not seen as a problem. In early democracies such as Greece and Rome, where elected officials debated to promote their points of view, eloquent and persuasive speech was considered more important than written language and readers fully expected that they would have to pore over a scroll before reciting it in public. To be able to understand a text on a first reading was unheard of: when asked to read aloud from an unfamiliar document, a 2nd Century writer named Aulus Gellius protested that he would mangle its meaning and emphasise its words incorrectly. (When a bystander stepped in to read the document instead, he did just that.)

Joining the dots

Aristophanes’ breakthrough was to suggest that readers could annotate their documents, relieving the unbroken stream of text with dots of ink aligned with the middle (·), bottom (.) or top (·) of each line. His ‘subordinate’, ‘intermediate’ and ‘full’ points corresponded to the pauses of increasing length that a practised reader would habitually insert between formal units of speech called the comma, colon and periodos. This was not quite punctuation as we know it – Aristophanes saw his marks as representing simple pauses rather than grammatical boundaries – but the seed had been planted.

Unfortunately, not everyone was convinced of the value of this new invention. When the Romans overtook the Greeks as the preeminent empire-builders of the ancient world, they abandoned Aristophanes’ system of dots without a second thought. Cicero, for example, one of Rome’s most famous public speakers, told his rapt audiences that the end of a sentence “ought to be determined not by the speaker’s pausing for breath, or by a stroke interposed by a copyist, but by the constraint of the rhythm”.

Books became an integral part of the Christian identity

And though the Romans had experimented for a while with separating·words·with·dots, by the second century CE they had abandoned that too. The cult of public speaking was a strong one, to the extent that all reading was done aloud: most scholars agree that the Greeks and Romans got round their lack of punctuation by murmuring aloud as they read through texts of all kinds.

Writing comes of age

It was the rise of a quite different kind of cult that resuscitated Aristophanes’ foray into punctuation. As the Roman Empire crumbled in the 4th and 5th Centuries, Rome’s pagans found themselves fighting a losing battle against a new religion called Christianity. Whereas pagans had always passed along their traditions and culture by word of mouth, Christians preferred to write down their psalms and gospels to better spread the word of God. Books became an integral part of the Christian identity, acquiring decorative letters and paragraph marks (Γ, ¢, 7, ¶ and others), and many were lavishly illustrated with gold leaf and intricate paintings.

As it spread across Europe, Christianity embraced writing and rejuvenated punctuation. In the 6th Century, Christian writers began to punctuate their own works long before readers got their hands on them in order to protect their original meaning. Later, in the 7th Century, Isidore of Seville (first an archbishop and later beatified to become a saint, though sadly not for his services to punctuation) described an updated version of Aristophanes’ system in which he rearranged the dots in order of height to indicate short (.), medium (·) and long (·) pauses respectively.

Moreover, Isidore explicitly connected punctuation with meaning for the first time: the re-christened subdistinctio, or low point (.), no longer marked a simple pause but was rather the signpost of a grammatical comma, while the high point, or distinctio finalis (·), stood for the end of a sentence. Spaces between words appeared soon after this, an invention of Irish and Scottish monks tired of prying apart unfamiliar Latin words. And towards the end of the 8th Century, in the nascent country of Germany, the famed king Charlemagne ordered a monk named Alcuin to devise a unified alphabet of letters that could be read by all his far-flung subjects, thus creating what we now know as lowercase letters. Writing had come of age, and punctuation was an indispensable part of it.

Cutting a dash

With Aristophanes’ little dots now commonplace, writers began to expand on them. Some borrowed from musical notation, inspired by Gregorian chants to create new marks like the punctus versus (a medieval ringer for the semicolon used to terminate a sentence) and the punctus elevatus (an upside-down ‘;’ that evolved into the modern colon) that suggested changes in tone as well as grammatical meaning. Another new mark, an ancestor of the question mark called the punctus interrogativus, was used to punctuate questions and to convey a rising inflection at the same time (The related exclamation mark came later, during the 15th Century.)

The three dots that had spawned punctuation in the first place inevitably suffered as a result. As other, more specific symbols were created, the distinction between low, medium and high points grew indistinct until all that was left was a simple point that could be placed anywhere on the line to indicate a pause of indeterminate length – a muddied mixture of the comma, colon and full stop. The humble dot was put under pressure on another front, too, when a 12th Century Italian writer named Boncompagno da Signa proposed an entirely new system of punctuation comprising only two marks: a slash (/) represented a pause while a dash (—) terminated sentences. The fate of da Signa’s dash is murky – it may or may not be the ancestor of the parenthetical dash, like those that surround these words – but the slash, or virgula suspensiva, was an unequivocal success. It was compact and visually distinctive, and it soon began to edge out the last holdouts of Aristophanes’s system as a general-purpose comma or pause.

This, then, was the state of punctuation at the height of the Renaissance: a mixture of ancient Greek dots; colons, question marks, and other marks descended from medieval symbols; and a few latecomers such as the slash and dash. By now writers were pretty comfortable with the way things stood, which was fortunate, really, because when printing arrived in the mid-1450s, with the publication of Johannes Gutenberg’s 42-line Bible, punctuation found itself unexpectedly frozen in time. Within 50 years, the majority of the symbols we use today were cast firmly in lead, never to change again: Boncompagno da Signa’s slash dropped to the baseline and gained a slight curve to become the modern comma, inheriting its old Greek name as it did so; the semicolon and the exclamation mark joined the colon and the question mark; and Aristophanes’s dot got one last hurrah as the full stop. After that the evolution of punctuation marks stopped dead, stymied by the standardisation imposed by the printing press.

It is only now, with computers more widespread than printing presses ever were, that punctuation is again showing signs of life. The average 15th Century writer would have little difficulty in identifying the marks of punctuation that grace the computer keyboard, but they might be a little more surprised by the emoticons and emoji that have joined them on our screens. Punctuation, it turns out, is not dead; it was just waiting for the next technological bandwagon on which to leap. Now we’ve found it, it’s up to us readers and writers once more to decide how we’re going to punctuate our words for the next 2,000 years.

Keith Houston is the author of Shady Characters, The Secret Life of Punctuation, Symbols & Other Typographical Marks. More of his work can be found here.

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