Simplex sigillum veri
“Simplicity is the seal of truth.”
Motto of Herman Boerhaave
What does “Simplex sigillum veri” mean?
Simplex sigillum veri translates as “Simplicity is the seal of truth.”
The truest explanations are often the simplest ones. It is an elegant reminder for scientists, writers and designers to prefer clarity over complication.
“Simplex sigillum veri” word by word
| Latin | English | Grammar |
|---|---|---|
| Simplex | simple, plain | nominative singular neuter (nominative) of the adjective simplex, “simple”; it agrees with sigillum |
| sigillum | seal, mark of authenticity | nominative singular neuter (nominative) of sigillum, “seal”; the subject of the sentence |
| veri | of truth | genitive singular neuter (genitive) of verum, “truth”, here used as a noun; “of the true” or “of truth” |
How to pronounce “Simplex sigillum veri”
The two differ in the g of sigillum (hard g in Classical, j in Church Latin) and in the v of veri (w in Classical, v in Church Latin). Stress falls on the first syllable of simplex and veri, and on the second-to-last syllable of sigillum.
The story behind it
Word for word the line says “plain (is) the seal of truth”. Latin leaves out the verb “is”, so a sentence like this is simply two nouns side by side, and the English “Simplicity is the seal of truth” spells out what the Latin implies.
It was the personal motto of Herman Boerhaave (1668-1738), the Dutch physician and teacher at Leiden, one of the most influential medical professors of his age. The line is therefore early modern, not ancient: it comes from a scientist writing in the Latin of the learned world of his day.
A seal in this sense is a mark that proves something is genuine, like the stamp pressed into wax on a document. Today the phrase is quoted by scientists, writers and designers who prefer clear, uncluttered solutions.
How to use “Simplex sigillum veri”
A good fit for a desk sign, lab or studio wall, a tattoo, or a motto for anyone who prizes clean, uncluttered work in science, writing, engineering or design. It also works as an epigraph for an essay on clarity or on Occam’s razor.
- Latin
- Simplex sigillum veri
- English
- Simplicity is the seal of truth.
- Source
- Motto of Herman Boerhaave
- Era
- Early modern
- Theme
- Truth
Common mistakes
- Simplex here means “plain, uncomplicated”, so the line does not claim that truth is always easy to find, only that true things tend to be simple in form.
- The Latin has no verb. Do not add est in the middle, as the short form is the traditional wording.
- The ending of simplex does not change for gender, but sigillum is neuter, so the adjective stays as simplex; do not write simplicis unless you want the genitive, which changes the meaning.
- The idea resembles Occam’s razor, but the two are not the same thing and this line is not from William of Ockham.
Questions about “Simplex sigillum veri”
What does “Simplex sigillum veri” mean literally?
“Simple (is) the seal of truth.” The Latin has no verb, so “is” is added in English. A sigillum is a seal that marks something as genuine.
Who said “Simplex sigillum veri”?
It was the personal motto of Herman Boerhaave, the Dutch physician and teacher (1668-1738). It is not an ancient Roman saying.
How do you pronounce “Simplex sigillum veri”?
In Classical Latin: SIM-pleks see-GIL-loom WEH-ree. In Church Latin: SIM-pleks see-JEEL-loom VEH-ree.
Is “Simplex sigillum veri” correct Latin for a tattoo?
Yes. It is a short, correct phrase of three words, and the missing verb is normal in Latin. Keep it exactly as written, since changing endings alters the meaning.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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