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Who really said it

In peace prepare for war, in war prepare for peace

Not Sun Tzu — an anonymous modern maxim Unknown (echoes the Roman maxim “Si vis pacem, para bellum”) Wording anonymous; earliest known Google Books appearance 1920, no attribution
Disputed Rights unconfirmed

This line is listed among Sun Tzu’s misattributed quotations ↗: it appears nowhere in The Art of War and is only “sometimes erroneously prepended” to its opening line. Its first half restates the ancient Roman maxim Si vis pacem, para bellum (“if you want peace, prepare for war”), traced to the writer Vegetius ↗; the neat “in war prepare for peace” reversal is a modern addition with no identifiable author.

Last verified 14 Jul 2026 · how we verify · spot an error?

For presentations

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Disputed credit — copy with the correction

“In peace prepare for war, in war prepare for peace” Anonymous modern maxim, often misattributed to Sun Tzu; echoes the Roman "Si vis pacem, para bellum" (Vegetius).

The slide-ready mistake: crediting this to Sun Tzu. Use the credit shown above instead.

Can you use it?

We couldn’t verify where this wording comes from, so there’s no rights status to give. Safe to present as an unverified or anonymous line — just don’t assert a specific author or source.

Image direction — grounded in this quote’s real context; paste into your image tool

In context

Evoking the world of Vegetius — Roman military writer. Theme: "In peace prepare for war, in war prepare for peace". Atmospheric and restrained, cinematic directional light, a muted period-appropriate palette, fine grain and texture. Compose with generous empty space for the quote and a small credit line. No lettering in the image itself.

Minimalist

Minimalist editorial slide for the quote "In peace prepare for war, in war prepare for peace". Clean background, a single muted accent color, generous negative space, subtle paper or linen texture, no literal illustration — let the words carry it. Reserve clear space for a serif quote and a small credit line. No lettering in the image itself.

Provenance

The record

Claimed author
Sun Tzu (孫子), c. 5th century BC
Verdict
Misattributed — not in The Art of War
Actual root
Roman maxim “Si vis pacem, para bellum”
Earliest known appearance
1920 in Google Books, in a pharmaceutical journal — no attribution given

In peace prepare for war, in war prepare for peace. Not in Sun Tzu’s text

Sun Tzu’s Art of War in fact opens: “The art of war is of vital importance to the State.” The line above is a separate modern saying that gets glued onto that opening.

Wikiquote: Sun Tzu — Misattributed

Why this isn’t Sun Tzu

The exact double-chiasmus wording has no identifiable author — its earliest known Google Books appearance (1920) carried no attribution — so no copyright status can be asserted for this phrasing. The two works it draws on, Sun Tzu’s Art of War and Vegetius’s Roman maxim, are both ancient and long in the public domain, but that does not attach to this particular modern saying.

Fact-check

How Sun Tzu got the credit

A clever, symmetrical war-and-peace line is exactly the kind of aphorism that drifts toward a famous strategist. Here the drift is documented.

Sun Tzu Misattributed

The line does not appear in The Art of War. Wikiquote lists it under Sun Tzu’s Misattributed quotations ↗, explaining it is merely “sometimes erroneously prepended to the opening line ‘The art of war is of vital importance to the State.’”

The Roman maxim / Vegetius Actual root

The first half restates Si vis pacem, para bellum (“if you want peace, prepare for war”), whose documented origin is Vegetius’s De re militari ↗ — a Roman, not a Chinese, source.

Bottom line: an anonymous modern saying that reverses a two-thousand-year-old Roman maxim, later pinned on Sun Tzu. Its earliest traced Google Books appearance is 1920, with no author named ↗.

Context

Why the mix-up sticks

Sun Tzu is one of the internet’s great quote magnets: any crisp aphorism about war, strategy or peace can be draped over his name and few readers will question it. The symmetry of this particular line — peace mirrored against war, war against peace — makes it feel ancient and Eastern, even though it is neither.

In reality the sentiment is Roman. Vegetius’s Si vis pacem, para bellum gave the West its enduring “prepare for war to keep the peace” maxim; the tidy “in war prepare for peace” counterpart is a modern rhetorical flourish that no primary text supports.

An anonymous modern reversal of a Roman maxim — not a sentence Sun Tzu ever wrote.

Explore

Filed under

More provenance-checked quotes on the same theme, each with its reuse status.

Wisdom Change

Go further

Dig deeper

Trusted places to keep pulling the thread — primary archives, fact-checks, and scholarship. We show how we used each one before you leave.

Wikiquote: Sun Tzu (Misattributed)en.wikiquote.org

Lists this line as misattributed and explains its link to the Roman motto.
Si vis pacem, para bellumen.wikipedia.org

Traces the “prepare for war” maxim to Vegetius’s De re militari.
Vegetiusen.wikipedia.org

Biography of the Roman writer behind the original maxim.
The Art of War (Giles translation)www.gutenberg.org

Full public-domain text of Sun Tzu — search it to confirm the line is absent.
Epitoma rei militaris (Latin)www.thelatinlibrary.com

The full Latin text of Vegetius’s treatise — the source of the Roman ‘prepare for war’ adage.

The documented root of the idea

Vegetius, and the Roman maxim behind the line

Vegetius

Late 4th century AD · Roman military writer

Publius Flavius Vegetius Renatus was a writer of the Later Roman Empire whose Epitoma rei militaris (also known as De re militari) is the only intact ancient manual of Roman military institutions. From it descends the famous adage Si vis pacem, para bellum — Vegetius’s own words were “Igitur qui desiderat pacem, praeparet bellum” (“therefore let him who desires peace prepare for war”). That maxim, not anything by Sun Tzu, is the true ancestor of the popular quote.

For writers & researchers

Cite this

Source & provenance

Earliest documented as misattributed in “Sun Tzu — Misattributed,” Wikiquote; underlying maxim from Publius Flavius Vegetius Renatus, Epitoma rei militaris (late 4th c. AD). Per Wikiquote, the phrase’s earliest Google Books appearance is 1920, without attribution.

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Quotle.info. “Who really said ‘In peace prepare for war, in war prepare for peace’?” Last verified 14 Jul 2026. https://quotle.info/who-said/in-peace-prepare-for-war-in-war-prepare-for-peace

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