Felix qui potuit rerum cognoscere causas
“Happy is the one who has been able to learn the causes of things.”
Virgil, Georgics 2.490
What does “Felix qui potuit rerum cognoscere causas” mean?
Felix qui potuit rerum cognoscere causas translates as “Happy is the one who has been able to learn the causes of things.”
Understanding how the world works brings contentment.
“Felix qui potuit rerum cognoscere causas” word by word
| Latin | English | Grammar |
|---|---|---|
| Felix | happy, fortunate | nominative singular masculine adjective (nominative case); here it means “the happy one”, with the person left unnamed |
| qui | who, the one who | nominative singular masculine relative pronoun (nominative case), the subject of potuit |
| potuit | was able, has been able | third person singular perfect active indicative of possum, “I am able” |
| rerum | of things | genitive plural of res, “thing, matter”, depending on causas |
| cognoscere | to learn, to come to know | present infinitive of cognosco, “I get to know”, completing potuit |
| causas | the causes | accusative plural of causa, “cause, reason”, the object of cognoscere |
How to pronounce “Felix qui potuit rerum cognoscere causas”
The main differences are the soft c in cognoscere (church: ‑NOHS-cheh-reh, classical: ‑NOHS-keh-reh) and the vowel sounds of the i endings. Stress falls on the first syllable of felix, potuit and rerum, on the second of cognoscere (the o is followed by two consonants), and on the first of causas.
The story behind it
Word for word the line says “Happy who was able to know the causes of things”. It comes from Virgil’s Georgics, a Latin poem about farming and country life written in the 1st century BC, in the second of its four books.
Virgil does not name the person. Readers have long taken the passage to refer to a thinker who understands nature and has overcome fear of fate and death. Some have linked it to Lucretius, the Epicurean poet, though Virgil does not say so.
The shortened form “Rerum cognoscere causas” (to know the causes of things) is used as a motto by the London School of Economics, the University of Sheffield and the University of Guelph. Today the full line is a favourite for anyone who values curiosity, science and learning.
How to use “Felix qui potuit rerum cognoscere causas”
A good fit for a tattoo or engraving for students, scientists and the endlessly curious, for a graduation card, or as a motto above a desk or library shelf. Use the short form “Rerum cognoscere causas” when you want a compact, motto-style phrase.
- Latin
- Felix qui potuit rerum cognoscere causas
- English
- Happy is the one who has been able to learn the causes of things.
- Source
- Virgil, Georgics 2.490
- Era
- Antiquity
- Theme
- Learning
Common mistakes
- Felix means “happy” or “fortunate”, not “lucky” in the sense of mere chance. The line is about the satisfaction of understanding.
- Rerum is genitive plural: “of things”. Rerum causas means “the causes of things”, not “things and causes”.
- The person is not named and nothing in the line says it is a man; felix qui is a general “happy is the one who”. Changing felix to felicior or felices changes the meaning.
- The shortened motto drops the word felix and the verb potuit, so it no longer says anything about happiness.
Questions about “Felix qui potuit rerum cognoscere causas”
What does “Felix qui potuit rerum cognoscere causas” mean literally?
“Happy (is he) who was able to know the causes of things.” The usual English rendering is “Happy is the one who has been able to learn the causes of things.”
Who wrote “Felix qui potuit rerum cognoscere causas”?
The Roman poet Virgil, in the Georgics, book 2, line 490. It was written in the 1st century BC.
How do you pronounce “Felix qui potuit rerum cognoscere causas”?
In classical Latin: FEH-liks kwee POH-too-it REH-room kog-NOHS-keh-reh KOW-sahs. In church Latin the c of cognoscere becomes “ch”.
Which universities use “Rerum cognoscere causas” as a motto?
The London School of Economics, the University of Sheffield and the University of Guelph use the shortened form.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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