Nemo sibi tantummodo errat, sed alieni erroris et causa et auctor est
“No one errs only for himself; he is also the cause and author of another’s error.”
Seneca, De vita beata 1.4
What does “Nemo sibi tantummodo errat, sed alieni erroris et causa et auctor est” mean?
Nemo sibi tantummodo errat, sed alieni erroris et causa et auctor est translates as “No one errs only for himself; he is also the cause and author of another’s error.”
Our mistakes spread. When we go wrong, we often lead others wrong too.
“Nemo sibi tantummodo errat, sed alieni …” word by word
| Latin | English | Grammar |
|---|---|---|
| Nemo | no one | nominative singular; from ne + homo, “not a man”; the subject of errat |
| sibi | for himself | dative singular of the reflexive pronoun sui; dative of disadvantage, “to his own harm” |
| tantummodo | only | adverb, “merely, only”; built from tantum + modo |
| errat | errs, goes astray | 3rd person singular present indicative active of erro, errare, “to wander, to err” |
| sed | but | conjunction; sets up the contrast with the first clause |
| alieni | of another | genitive singular neuter of alienus, “belonging to another”; agrees with erroris |
| erroris | of error | genitive singular of error, “a wandering, a mistake”; depends on causa and auctor |
| et | both | conjunction; paired with the next et as “both … and” |
| causa | cause | nominative singular of causa, “cause, reason”; predicate noun after est |
| et | and | second part of the pair “et … et” |
| auctor | author, originator | nominative singular of auctor, “originator, promoter”; predicate noun after est |
| est | is | 3rd person singular present indicative of sum, “to be”; its subject is nemo |
How to pronounce “Nemo sibi tantummodo errat, sed alieni …”
The two systems differ mainly in sibi (SIB-ee or SEE-bee) and causa (the s is a plain s in Classical, nearer a z in Church Latin). Elsewhere they sound very close. In tantummodo the stress falls on the long vowel in the third syllable from the end, and in erroris on the second-to-last syllable.
The story behind it
Word for word the line says that no one goes wrong only for himself, but is both the cause and the author of another’s mistake. Seneca the Younger, the Roman Stoic philosopher and statesman, writes it near the opening of his essay De vita beata (“On the Happy Life”).
The essay asks how to live well, and Seneca starts with a warning: do not simply follow the crowd. People copy what others do and say, and mistaken opinions pass from one person to the next like a contagion.
That is why the line fits any talk of influence. Whoever follows the herd also adds to it, and so becomes a cause of other people’s errors, not just of his own.
How to use “Nemo sibi tantummodo errat, sed alieni …”
Suited to a speech or essay on influence, peer pressure, leadership or responsibility, or a motto for a teacher, parent or manager. As a tattoo or desk motto it works for someone who wants to think before they set an example.
- Latin
- Nemo sibi tantummodo errat, sed alieni erroris et causa et auctor est
- English
- No one errs only for himself; he is also the cause and author of another’s error.
- Source
- Seneca, De vita beata 1.4
- Era
- Classical
- Theme
- Wisdom
Common mistakes
- The Latin is long and the grammar is tricky: sibi is the reflexive “for himself”, so changing it to “for myself” or “for yourself” means rewriting the sentence, not just swapping a word.
- Do not read nemo as a name. It is the ordinary word for “no one”.
- The line is often shortened to a few words online, which loses the point that the error spreads to others.
- It does not say that all mistakes are someone else’s fault. It says that each of us helps cause the mistakes of others.
Questions about “Nemo sibi tantummodo errat, sed alieni …”
What does “Nemo sibi tantummodo errat” mean literally?
Literally, “No one errs only for himself”. The full sentence goes on to say that he is also the cause and author of another’s error.
Who said “Nemo sibi tantummodo errat”?
It comes from Seneca the Younger, in De vita beata 1.4, an essay written in the 1st century AD.
How do you pronounce “Nemo sibi tantummodo errat”?
In Classical Latin it is NEH-moh SIB-ee tan-TOOM-moh-doh ER-rat. In Church Latin, sibi becomes SEE-bee.
Is “Nemo sibi tantummodo errat” good Latin for a tattoo?
Yes, it is correct and taken from a real source. It is long, though, so check the spacing and spelling carefully, and avoid changing individual words yourself.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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