Actus dicatur bonus qui est conformis legi et rationi
“An act should be called good when it is in accordance with law and reason.”
Latin maxim of moral philosophy
What does “Actus dicatur bonus qui est conformis legi et rationi” mean?
Actus dicatur bonus qui est conformis legi et rationi translates as “An act should be called good when it is in accordance with law and reason.”
The goodness of an action is measured by two standards: whether it agrees with the law and whether it agrees with right reason. The maxim reflects a tradition in which morality is not a matter of mood but of rational and lawful order.
“Actus dicatur bonus qui est conformis …” word by word
| Latin | English | Grammar |
|---|---|---|
| Actus | act, deed | nominative singular masculine of actus, “act, deed”; the subject of the sentence |
| dicatur | let it be called, should be called | present subjunctive passive, 3rd person singular, of dico, “to say, call”; the subjunctive gives the sense of “should be called” |
| bonus | good | nominative singular masculine of bonus, “good”; completes the verb, so “be called good” |
| qui | which, that | nominative singular masculine relative pronoun (qui, quae, quod); refers back to actus |
| est | is | present indicative active, 3rd person singular, of sum, “to be” |
| conformis | in accordance with, conforming to | nominative singular masculine/feminine of conformis, “conformable, in agreement”; takes the dative |
| legi | to law | dative singular of lex, “law”; the thing the act conforms to |
| et | and | conjunction joining legi and rationi |
| rationi | to reason | dative singular of ratio, “reason”; the second thing the act conforms to |
How to pronounce “Actus dicatur bonus qui est conformis …”
The main differences are the g in legi (hard in Classical, like j in Church) and the ti in rationi (a plain t in Classical, ts in Church). In dicatur the stress falls on the middle syllable, ca, in both.
The story behind it
Word for word the line says “let that act be called good which is conformable to law and reason”. It is a rule for when the word “good” may properly be applied to a human action.
It belongs to the scholastic and moral-theological tradition of the Middle Ages, which judged human acts by their agreement with law and right reason. Its exact first author is not documented, so it is best treated as a maxim of that tradition, not a quotation from one named writer.
The pairing of law and reason echoes a wider tradition in which good action follows a rational order. Today the line suits discussions of ethics, professional conduct and the difference between mere preference and principled judgment.
How to use “Actus dicatur bonus qui est conformis …”
Fits an ethics seminar, a compliance or professional-conduct training, an essay on law and morality, or a motto for someone who wants their choices guided by principle rather than mood.
- Latin
- Actus dicatur bonus qui est conformis legi et rationi
- English
- An act should be called good when it is in accordance with law and reason.
- Source
- Latin maxim of moral philosophy
- Era
- Middle Ages
- Theme
- Virtue
Common mistakes
- Do not read it as “whatever is legal is good”. Reason is named as a second, equal standard alongside law.
- Conformis takes the dative, so it is legi et rationi (“to law and reason”). Writing legem et rationem is incorrect here.
- Dicatur is a subjunctive meaning “should be called”, not a plain statement that all such acts are called good.
- Do not attribute it to Aquinas or any other named author as a verbatim quotation; its first author is not documented.
Questions about “Actus dicatur bonus qui est conformis …”
What does “Actus dicatur bonus qui est conformis legi et rationi” mean?
“An act should be called good when it is in accordance with law and reason.” It gives two tests for calling an action good.
Who said “Actus dicatur bonus qui est conformis legi et rationi”?
No single author is documented. It is a maxim of the scholastic and moral-theological tradition of the Middle Ages.
How do you pronounce “Actus dicatur bonus”?
Classically: AK-toos dih-KAH-toor BOH-noos. In Church Latin the first two words sound much the same, with the i in dicatur closer to “dee”.
Is “Actus dicatur bonus qui est conformis legi et rationi” good for a tattoo?
The Latin is correct as written. It is long, so many people pick a shorter line; if you change it, keep the dative endings after conformis.
More to explore
Translation and grammar checked by Latin Quoter · last reviewed November 2026
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