Summary of The Em Dash

Overview of The Em Dash (99% Invisible)

This episode (hosted by Roman Mars) traces the long literary life of the em dash—its origins, its roles in theater, novels and poetry, the 19th‑century “golden age” of dash usage, and the recent controversy where heavy em‑dash use became a signal (sometimes unfairly) of AI‑written text. The show explains why LLMs began overusing em dashes, explores a design response called the “Am‑dash,” and situates the punctuation debate within a larger worry about outsourcing thought to machines.

Key points and main takeaways

• The em dash is a flexible punctuation mark used for pauses, interruptions, parenthetical thought, censorship/redaction, and rhetorical effect.
• Its lineage goes back to medieval punctuation reforms (Bon Compagno) and evolved through theater (aposiopesis) into novelistic and poetic practice.
• The 19th century saw massive em‑dash adoption (Dickens, Melville, Brontë). Emily Dickinson used dashes extensively; early editors removed most of them.
• Modern LLMs began producing em dashes abundantly (mid‑2024 onward), which led some readers to treat em dashes as an “AI fingerprint.”
• A Sydney design studio (Coco‑Gun) created the “Am‑dash” and two fonts (Times New Human, A Real) as a playful, human‑made alternative—type “am-” + hyphen to insert it.
• The episode emphasizes that em‑dash presence alone is a poor signal of AI authorship; the larger worry is people surrendering thinking to machines.

History of the em dash

• Medieval punctuation: Bon Compagno (Ars Dictaminis) introduced two marks—a vertical slash (pause → evolved into comma) and a horizontal dash (sentence end → ancestor of en/em dash).
• Theater (16th–17th c.): Playwrights used dashes to show interrupted speech and thinking pauses (Shakespeare’s First Folio is full of dashes used for aposiopesis).
• Novelistic adoption (18th–19th c.): Novelists used dashes to reproduce spoken cadence, stream‑of‑consciousness, and to redact names or facts to create realism (e.g., Lawrence Sterne’s Tristram Shandy; Jane Austen used dashes for redaction and effect).
• 19th‑century bloom: Study shows em‑dash usage spiked. Examples cited: Oliver Twist ~1 dash/224 words; Moby‑Dick ~1 per 129 words; Jane Eyre ~1 per 90 words.
• Emily Dickinson: prolific dash user; when her poems were first edited/published (1890), editors removed most of her dashes—only 52 of 1,151 were kept.

Literary uses and controversies

• Functions: substitute for commas/colons/parentheses, indicate interruption, dramatic pause, U‑turn in thought, perform censorship/redaction.
• Critics historically protested overuse (Jonathan Swift, anonymous reviews of Byron). Modern style guides (Chicago Manual of Style) caution against excessive em‑dash use—“if in doubt, edit them out.”
• Supporters argue the em dash makes prose feel more human and mimics real thought patterns.

Em dash and AI

• Observation: By 2024–2025 many readers noticed LLMs (ChatGPT, Claude, etc.) overusing long em dashes—prompting the “ChatGPT hyphen” meme.
• Possible cause: As models expanded training data, companies reportedly performed large‑scale digitization (including scanning print books). Models may have absorbed older literature’s heavy em‑dash style and reproduced it in modern contexts.
• Sam Altman (OpenAI) joked the dash style was a product decision—users liked dashes—while others suspect deeper training‑data effects.
• Important caveat: an em dash alone is not reliable proof of AI authorship. Tone, vocabulary, and a certain blandness are usually stronger hints.

The Am‑dash (design response)

• Creators: Coco‑Gun (Sydney) designed a new glyph—the “Am‑dash”—a stylized em dash with curved/serifed ends (described like a 1920s pencil mustache).
• Purpose: a playful, human signaling device to show text was written by a person and not an LLM; also framed as a cultural rebuttal to AI overreach.
• How to use: download two fonts (Times New Human or A Real) from theamdash.com. Type “am-” + hyphen to produce the glyph.
• Adoption & ambitions: thousands of downloads since its May 2025 launch; creators hope for broader visibility and eventual Unicode acceptance.

Notable quotes and moments

• Keith Houston: the dash “allows you to do a kind of a U‑turn within a sentence” and is “useful for special effects.”
• On theater: dashes in Shakespeare’s First Folio signal pauses, interruptions and expressiveness.
• Fiona Green (Emily Dickinson scholar): Dickinson’s dashes contribute to the poems’ “unfinishedness” and ambiguity; removing them changed the look (though not necessarily the meter).
• Ant Mulder (Coco‑Gun): Am‑dash was “rooted in a real love of writing” and intended as a human‑made response to AI.
• Roman Mars quip: the episode itself contained 68 em‑dashes.

Practical notes / Recommendations

• Don’t assume em dash = AI. Use holistic cues (tone, specificity, structure) to judge authorship.
• If you like em dashes, use them intentionally—avoid overuse that reduces clarity.
• To try the Am‑dash: visit theamdash.com, download fonts, and type “am-” to insert. Understand this is a cultural/design statement as much as a typographic tool.
• Be mindful about outsourcing thinking: educators in the episode stress the value of the process of grappling with complex texts rather than having machines do it for you.

Further reading & resources

• Shady Characters by Keith Houston (history of punctuation).
• Theamdash.com — download fonts and instructions.
• 99percentinvisible.org — episode page and past episodes.

This summary captures the episode’s arc: a punctuation mark with centuries of expressive use became entangled in a modern panic about AI, prompting both design play (the Am‑dash) and broader reflection on what we lose when we outsource thinking to machines.