A History of Parentheses

So, let’s pull back the curtain (or, perhaps, open the parenthesis) on one of typography’s most versatile players.

Before the Curve: The Need for an Aside

To understand where parentheses came from, we first have to appreciate a time when they didn’t exist. In ancient Greek and Roman texts, sentences often ran together without spaces or punctuation, a style called scriptio continua. Reading was a laborious act of deciphering a solid block of letters. Over centuries, scholars and scribes began introducing marks to make texts easier to read and interpret.

One of the earliest conceptual ancestors of the parenthesis was the diple (Greek for “double”), a chevron-like mark (>) placed in the margin. Around the 2nd century BCE, the famed librarian Aristarchus of Samothrace used it to mark lines in Homeric poems that he considered questionable or noteworthy. While the diple didn’t enclose text, it was one of the first formal systems for flagging a piece of information as separate from the main narrative. It established the *need* for a way to say, “Hey, reader, pay attention to this bit—it’s a little different.”

The Birth of the Bracket: A Humanist’s Innovation

Fast forward over a millennium to late 14th-century Florence, a hub of the Renaissance. Here we meet the person largely credited with inventing the parenthesis as we know it: the Italian humanist and chancellor Coluccio Salutati. Around 1399, while annotating and copying classical texts, Salutati needed a way to insert his own corrections or explanatory notes directly into the text without confusing them with the original author’s words.

His solution was ingenious. He began using angular brackets () or half-box-shaped marks ⌊ ⌋ to set off his own additions. It was the perfect tool. The enclosed text was visually distinct, clearly an insertion by the scribe or commentator. It was like he was leaning in to whisper a helpful but non-essential clarification directly to the reader.

The name itself, “parenthesis”, tells us everything about its function. It comes from the Greek words para- (“beside”), en- (“in”), and thesis (“placing”). A parenthesis is, quite literally, a “placing in beside.”

The Age of Print and the Rise of the “Little Moons”

Salutati’s invention might have remained a niche scribal tool if not for another world-changing technology: the printing press. As printers like Aldus Manutius began mass-producing books in the 15th and 16th centuries, they needed to standardize punctuation for legibility and consistency.

During this period, the sharp, angular brackets gave way to the softer, curved form () we use today. These elegant curves were known to printers as lunulae, or “little moons.” The influential Dutch scholar and humanist Erasmus was a huge fan, and he used parentheses extensively in his widely published works. His adoption helped cement their place in the standard toolkit of Western typography.

By the 17th century, the parenthesis was a fully established grammatical mark. Its role was clear: to enclose information that was supplementary, an aside that could be removed without destroying the sentence’s fundamental meaning. It offered a different flavor of interruption—softer and more subtle than the abrupt stop of an em dash, and more detached than a clause set off by commas.

Consider this example:

The Queen (who was known for her love of Corgis) greeted the ambassador warmly.

The information about the Corgis is interesting context, but it’s not essential to the main point. The parentheses signal to us that this is a “by the way” comment.

Beyond Grammar: The Parenthesis in the Digital Age

For centuries, the parenthesis played its grammatical role dutifully. But the 20th and 21st centuries gave it a dazzling new array of jobs, transforming it from a purely literary device into a powerhouse of technical and social communication.

In Math and Code

In mathematics and science, parentheses became absolutely critical for denoting the order of operations. Everyone who has taken a basic algebra class knows that (2 + 3) * 4 gives a very different result from 2 + 3 * 4. They eliminate ambiguity and enforce a logical sequence.

This logical function made them a natural fit for computer programming. In countless languages, from Python to Java to C++, parentheses are used to:

• Enclose arguments for functions: print("Hello, world!")
• Group expressions for evaluation: if (userIsLoggedIn && userHasPermissions)
• Define the structure of the code itself, most famously in LISP, which earned the affectionate (and sometimes frustrating) nickname “Lots of Irritating Superfluous Parentheses.”

In Digital Conversation

Perhaps the most radical evolution of the parenthesis happened with the rise of the internet. In the plain-text world of early email, forums, and chat rooms, users needed a way to convey tone and emotion without body language or vocal inflection. The parenthesis stepped in to help.

The most iconic invention was, of course, the emoticon. In 1982, Scott Fahlman proposed using :-) and :-( on a university message board to distinguish jokes from serious statements. The parenthesis, once a “little moon”, was now half of a human smile.

From there, its informal uses exploded:

• Tone Indicators: Adding (jk), (sarcasm), or (seriously) to clarify intent.
• Action Descriptions: Mimicking stage directions to add a layer of action or internal thought, as in (waves) or (slowly backs away).
• The “Hug”: Using parentheses to enclose a person’s name or a word to signify a virtual hug, like (((hugs))) or (you).

A Mark of a Thousand Faces

From a scribe’s marginalia to a programmer’s function call, from a grammatical aside to a digital smile, the history of the parenthesis is a story of evolution. It shows how a simple mark can be adapted, reinvented, and repurposed to meet the changing demands of human communication.

So the next time you type a pair of these humble curves, take a moment to appreciate the journey they’ve taken. They are more than just punctuation; they are a testament to our ongoing, collective effort to make our words clearer, richer, and more human—even (and especially) through a screen.