Double Dative

The double dative combines two distinct dative relations in one clause. One is a dative of purpose, usually an abstract noun naming a function or result; the other is a dative of reference, advantage, or disadvantage, naming the person or thing for whom that function holds. Thus haec rēs mihi cūrae est is literally “this matter is for a concern to me” and idiomatically “this matter concerns me.” The two forms share a case, not a job.

The two datives

The pattern can be represented as:

subject or object + dative of reference + dative of purpose + governing verb

Word order is flexible. Meaning and lexical type, not first or second position, identify each role.

In the second example, ūsuī names the function, “for use,” and nōbīs names the people who benefited. Magnō is also dative because it agrees with ūsuī; it does not create a third dative role.

Double datives with sum

Forms of sum are the most frequent host. The nominative subject is evaluated as serving a function or producing an effect for the reference dative.

These English translations use an adjective, a verb, and a prepositional phrase. The Latin construction remains structurally parallel in all three. Honōrī, salūtī, and impedīmentō name credit, preservation, and hindrance as results; tibi, cīvitātī, and hostibus identify whose credit, safety, or hindrance is at issue.

The label “purpose” can sound as though a conscious planner must intend the result. That is too narrow. With salūtī or impedīmentō, the dative may describe an actual effect recognized after the event. Traditional “dative of purpose or result” captures this range better.

With coming, sending, and leaving

The pattern also occurs with verbs that place people or things into a role: veniō “come,” mittō “send,” relinquō “leave,” and similar verbs.

In the last example, legiōnēs is the accusative direct object of relīquit. Praesidiō gives the role assigned to those legions, while castrīs identifies what receives the protection. The ending -īs could be dative or ablative in isolation; the paired meaning “as protection for the camp” establishes the dative analysis.

This military and administrative use is common in Classical historical prose and naturally belongs to a (formal) register. It is not a poetic anomaly. Poets may separate the two datives or vary their order (literary), but prose already permits considerable word-order freedom.

Cui bonō?

The compact question cui bonō? is a famous elliptical double dative. Cui asks for the interested person, while bonō is a purpose/result dative: “to whose benefit?” or “who stood to gain?”

It does not literally mean “what good?” That would ask about the value of something rather than the beneficiary. The phrase is especially at home in (formal) forensic reasoning, where motive is inferred by identifying who profited.

How to parse without translating too early

When two apparently dative forms occur, use this sequence:

1. Identify the governing verb. Forms of sum and verbs of coming, sending, giving, or leaving are common hosts.
2. Find the nominative subject and any accusative direct object; do not assign those roles by English word order.
3. Test whether one dative is an abstract functional noun from the established purpose set.
4. Interpret the other dative as the person, group, or thing for whom that function or effect holds.
5. Paraphrase the structure: “X is/comes/is sent as Y for Z.” Only then choose natural English.

This method matters because a single English “for” can express either half. “Reinforcements for the infantry” may describe the functional aid or its beneficiary; Latin peditibus subsidiō states both separately.

Contrasts with neighboring datives

Additions to a sentence can completely change the analysis:

The purpose noun is the decisive extra element. In mihi liber est, mihi places the book in someone’s possession. In mihi liber ūsuī est, mihi is the person with reference to whom the book fulfills the function ūsuī.

The reference dative often has a beneficial or harmful interpretation, so traditional descriptions may call it a dative of advantage or disadvantage. That terminological overlap is real, not an error. What makes the construction “double” is its combination with the purpose/result dative. Compare the components separately on the dative of purpose and dative of reference pages.

Productivity and lexical limits

The syntactic frame is productive in Classical Latin, but the purpose slot is lexically narrow. Common nouns include cūrae “for concern,” ūsuī “for use,” auxiliō “for aid,” praesidiō “for protection,” subsidiō “for support,” salūtī “for safety,” honōrī or laudī “for credit,” vitiō “as a fault,” and impedīmentō “as a hindrance.” The purpose noun is normally abstract and singular. It is usually unmodified except by a degree adjective such as magnō or minōrī, or by a dependent genitive; magnō ūsuī is therefore an established pattern, not permission to add arbitrary descriptive adjectives. Nor is there a reliable license to place any convenient English predicate noun in the dative. Later (formal) Latin keeps the construction alive, but later frequency does not make unattested combinations Classical.

Common Mistakes

1. Making the purpose noun nominative because English uses “is.”

2. Putting the affected thing in the accusative after relinquō.

3. Failing to make an adjective agree with the purpose dative.

4. Reading cui bonō? as “what good?” and changing its cases.

Key Takeaways

The double dative contains one dative of purpose or result and one dative of reference, advantage, or disadvantage. Find the narrow purpose vocabulary first, identify the affected party second, and then translate the whole relation idiomatically. Its compactness is precisely why English may need an adjective, a verb, or an expanded phrase where Latin uses two case-marked nouns.