edited by Meagan Ayer et al.

Other Uses of the Infinitive

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Infinitive with Subject Accusative

459. The infinitive with subject accusative is used with verbs and other expressions of knowing, thinking, telling, and perceiving (Indirect Discourse, § 579).

Dīcit montem ab hostibus tenērī. (B. G. 1.22)
He says that the hill is held by the enemy.
[Direct: mōns ab hostibus tenētur.]


Infinitive of Purpose

460. In a few cases the infinitive retains its original meaning of purpose.

a. The infinitive is used in isolated passages instead of a subjunctive clause after habeō, , and ministrō.

Tantum habeō pollicērī. (Fam. 1.5 A. 3)
So much I have to promise.
[Here the more formal construction would be quod pollicear.]

ut Iovī bibere ministrāret (Tusc. 1.65)
to serve Jove with wine (to drink).

merīdiē bibere datō (Cato R. R. 89)
give (to) drink at noonday.

b. Parātus, suētus, and their compounds, and a few other participles (used as adjectives), take the Infinitive like the verbs from which they come.

id quod parātī sunt facere (Quint. 8)
that which they are ready to do

adsuēfactī superārī (B. G. 6.24)
used to being conquered

currū succēdere suētī (Aen. 3.541)
used to being harnessed to the chariot

cōpiās bellāre cōnsuētās (B. Afr. 73)
forces accustomed to fighting

Note— In prose these words more commonly take the gerund or gerundive construction (§ 503 ff.) either in the genitive, the dative, or the accusative with ad.

īnsuētus nāvigandī (B. G. 5.6)
unused to making voyages

alendīs līberīs suēti (Tac. Ann. 14.27)
accustomed to supporting children

corpora īnsuēta ad onera portanda (B. C. 1.78)
bodies unused to carry burdens

c. The poets and early writers often use the infinitive to express purpose when there is no analogy with any prose construction.

Fīlius intrō iit vidēre quid agat. (Ter. Hec. 345)
Your son has gone in to see what he is doing.
[In prose: the Supine vīsum]

Nōn ferrō Libycōs populāre Penātīs vēnimus. (Aen. 1.527)
We have not come to lay waste with the sword the Libyan homes.

Lōrīcam dōnat habērevirō (id. 5.262)
He gives the hero a breastplate to wear.
[In prose: habendam]

Note— So rarely in prose writers of the classic period. For the infinitive used instead of a Substantive Clause of Purpose, see § 457. For tempus est abīre, see § 504, Note 2.


Peculiar Infinitives

461. Many adjectives take the Infinitive in poetry, following a Greek idiom.

dūrus compōnere versūs (Hor. S. 1.4.8)
harsh in composing verse

cantārī dīgnus (Ecl. 5.54)
worthy to be sung
[In prose: quī cantētur]

fortis trāctāre serpentīs (Hor. Od. 1.37.26)
brave to handle serpents

cantāre perītī (Ecl. 10.32)
skilled in song

facilēs aurem praebēre (Prop. 3.14.15)
ready to lend an ear

nescia vincī pectora (Aen. 12.527)
hearts not knowing how to yield

tē vidēre aegrōtī (Plaut. Trin. 75)
sick of seeing you

a. Rarely in poetry the infinitive is used to express result.

Fingit equum docilem magister īreviam quā mōnstret eques. (Hor. Ep. 1.2.64)
The trainer makes the horse gentle so as to go in the road the rider points out.

Hīc levāre . . . pauperem labōribus vocātus audit (Hor. Od. 2.18.38)
He, when called, hears, so as to relieve the poor man of his troubles.

Note— These poetic constructions were originally regular and belong to the infinitive as a noun in the dative or locative case (§ 451). They had been supplanted, however, by other more formal constructions, and were afterwards restored in part through Greek influence.

b. The infinitive occasionally occurs as a pure noun limited by a demonstrative, a possessive, or some other adjective.

hōc nōn dolēre (Fin. 2.18)
this freedom from pain

Cf. tōtum hōc beātē vīvere (Tusc. 5.33)
this whole matter of the happy life

nostrum vīvere (Per. 1.9)
our life (to live)

scire tuum (id. 1.27)
your knowledge (to know)


Exclamatory Infinitive

462. The infinitive, with subject accusative,1 may be used in exclamations (cf. § 397. d).

Tē in tantās aerumnās propter mē incidisse! (Fam. 14.1)
Alas, that you should have fallen into such grief for me!

Mēne inceptō dēsisterevictam (Aen. 1.37)
What! I beaten desist from my purpose?

Note 1— The interrogative particle -ne is often attached to the emphatic word (as in the second example).

Note 2— The present and the perfect infinitive are used in this construction with their ordinary distinction of time (§ 486).

a. A subjunctive clause, with or without ut, is often used elliptically in exclamatory questions. The question may be introduced by the interrogative -ne.

Quamquam quid loquor? Tē ut ūlla rēs frangat! (Cat. 1.22)
Yet why do I speak? [The idea] that anything should bend you!

Egone ut tē interpellem (Tusc. 2.42)
What, I interrupt you?

Ego tibi īrāscerer (Q. Fr. 1.3)
I angry with you?

Note— The infinitive in exclamations usually refers to something actually occurring; the subjunctive, to something contemplated.


Historical Infinitive

463. The infinitive is often used for the imperfect indicative in narration, and takes a subject in the nominative.

Tum Catilīna pollicērī novās tabulās. (Sall. Cat. 21)
Then Catiline promised abolition of debts (clean ledgers).

Ego īnstāre ut mihi respondēret. (Verr. 2.188)
I kept urging him to answer me.

Pars cēdere, aliī īnsequī; neque sīgna neque ōrdinēs observāre; ubi quemque perīculum cēperat, ibi resistere ac prōpulsāre; arma, tēla, equī, virī, hostēs atque cīvēs permixtī; nihil cōnsiliō neque imperiō agī; fors omnia regere. (Iug. 51)
A part give way, others press on; they hold neither to standards nor ranks; where danger overtook them, there each would stand and fight; arms, weapons, horses, men, foe and friend, mingled in confusion; nothing went by counsel or command; chance ruled all.

Note— This construction is not strictly historical, but rather descriptive, and is never used to state a mere historical fact. It is rarely found in subordinate clauses. Though occurring in most of the writers of all periods, it is most frequent in the historians Sallust, Livy, Tacitus. It does not occur in Suetonius.


1. This construction is elliptical; that is, the thought is quoted in indirect discourse, though no verb of saying etc. is expressed or even, perhaps, implied (compare the French dire que). Passages like hancine ego ad rem nātam miseram mē memorābō? (Plaut. Rud. 188) point to the origin of the construction.