Gerunds and gerundives

Both are made from the same stem with -nd-: amandum, monendum, regendum, audiendum. They look alike, but they do different jobs.

• The gerund is a verbal noun, the English “…ing” in “the art of writing”. It is always neuter singular and never agrees with anything.
• The gerundive is a verbal adjective, amandus, -a, -um, “to be loved”. Like any adjective it agrees with a noun in case, number and gender.

hominēs bellandī cupidī
“men eager for fighting”: a gerund, a noun in the genitive after cupidī. (Caesar)

studium bellī gerendī
“eagerness for waging war”: a gerundive, gerendī agreeing with bellī. (Caesar)

Most of the time the two are translated the same way, with an English “…ing”. The difference matters for recognizing the grammar, and above all for spotting the one use that has no English “…ing” at all, the passive periphrastic (“must be done”).

The gerund has only four forms, and no nominative:

• Genitive amandī “of loving”, after nouns and adjectives: ars, spēs, facultās, studium, cupidus, perītus, and with causā.
• Dative amandō “for loving”, which is rare.
• Accusative amandum, only after a preposition, nearly always ad: ad amandum “for loving, to love”.
• Ablative amandō “by loving”, alone or after in, dē, ab, ex.

Where English uses “…ing” as the subject of a verb, or as the object of a verb such as “like” or “begin”, Latin uses the infinitive instead: “Seeing is believing” is said with two infinitives, not gerunds.

Et mihi discendī et tibi docendī facultātem ōtium praebet.
“Leisure gives me the chance of learning and you the chance of teaching.” (Pliny)

Tū Maxumus ille es,
ūnus quī nōbīs cūnctandō restituis rem.
“You are that famous Maximus, the one man who restores our state by delaying.” (Vergil)

Audīte: ecce exiit sēmināns ad sēminandum.
“Listen: see, the sower went out to sow.” (Vulgate)

Older Latin, and writers who like an old-fashioned flavor such as Sallust, spell the ending -undī, -undō, -undum: vigilandō, agundō, bene cōnsulundō prospera omnia cēdunt, “by keeping watch, by acting, by taking good counsel, all things turn out well” (Sallust).

The gerundive declines like bonus, -a, -um and agrees with its noun. Its basic meaning is passive and looks forward: laudandus is “(one) to be praised”, “who ought to be praised”. Standing on its own, especially with a form of sum, it keeps that meaning:

Cuius ratiō etsī nōn valuit, tamen magnō opere est laudanda.
“Although his plan did not prevail, it is nevertheless greatly to be praised.” (Nepos)

But most gerundives you meet sit inside a phrase with a noun, doing the work of a gerund, and there the passive idea disappears in English. A phrase like pācis petendae causā is literally “for the sake of peace to be sought”, but it means “in order to ask for peace”.

Menapiī lēgātōs ad eum pācis petendae causā mittunt.
“The Menapii sent envoys to him to ask for peace.” (Caesar)

When the verb has a direct object, Latin usually does not write a gerund with an accusative after it. Instead it puts the object into the case the gerund would have had, and turns the gerund into a gerundive agreeing with it:

• bellum gerere “to wage war”
• gerund + object: studium bellum gerendī (possible, but avoided)
• gerundive: studium bellī gerendī (the normal Latin)

Both mean “eagerness for waging war”. So cupidus bellī gerendī, not cupidus bellum gerendī; ad urbem capiendam, not ad urbem capiendum. Translate the noun as the object of an English “…ing”: studiō etiam videndae novae urbis, “also out of eagerness to see the new city” (Livy).

The gerundive phrase can stand in any case the gerund could, including the dative and the ablative:

mē Albānī gerendō bellō ducem creāvēre.
“The Albans have made me their leader for waging the war.” (Livy)

Antiochus autem sī tam in gerendō bellō cōnsiliīs eius pārēre voluisset, quam in suscipiendō īnstituerat …
“But if Antiochus had been as willing to follow his advice in waging the war as he had been in undertaking it …” (Nepos)

A gerund with a direct object does occur, most often when the object is a pronoun, and freely in later Latin: ad cōnsulendum tē dēcucurrī, “I have hurried to consult you” (Pliny); potestātem in terrā dīmittendī peccāta, “power on earth to forgive sins” (Vulgate).

One small trap: with the reflexive suī the gerundive is always -ndī, whatever the gender or number of the person meant: dissimulandī causā aut suī expūrgandī, “to hide his intentions or to clear himself” (Sallust).

Two very common ways of saying “in order to” use the gerund or gerundive:

• ad + accusative, placed before the phrase: ad pugnandum “to fight”, ad conventūs agendōs “to hold the assizes”.
• genitive + causā (or grātiā), placed after the phrase: praedandī causā “to plunder”, pācis petendae causā “to ask for peace”.

Quiētā Galliā Caesar, ut cōnstituerat, in Ītaliam ad conventūs agendōs proficīscitur.
“With Gaul quiet, Caesar set out for Italy, as he had decided, to hold the assizes.” (Caesar)

Vīvis, et vīvis nōn ad dēpōnendam, sed ad cōnfirmandam audāciam.
“You live, and you live not to lay aside your recklessness but to strengthen it.” (Cicero)

Quid, quod tū tē in custōdiam dedistī, quod vītandae suspīciōnis causā ad M'. Lepidum tē habitāre velle dīxistī?
“What of the fact that you gave yourself into custody, that to avoid suspicion you said you wanted to live at the house of Manius Lepidus?” (Cicero)

The English is the same as for a purpose clause with ut: “to …”, “in order to …”, “so as to …”. After nouns and adjectives, ad + gerund often means “for …ing” rather than purpose: ad nāvigandum paene inūtilis “almost useless for sailing” (Ritchie).

The gerundive with a form of sum expresses what has to be done: laudanda est, “it is to be praised, it must be praised”. This is called the passive periphrastic. The tense is carried by sum: est “must be”, erat “had to be”, erit “will have to be”. With a negative it means “must not” or “need not”: Nōn est saepius in ūnō homine summa salūs perīclitanda reī pūblicae, “The safety of the state must not be put at risk too often in the person of one man” (Cicero).

The person who has to do the job goes in the dative, the dative of agent. It is usually best to make that person the subject of an active English verb:

Caesarī omnia ūnō tempore erant agenda.
Literally: “Everything was to be done by Caesar at one time.” Naturally: “Caesar had everything to do at once.” (Caesar)

With an intransitive verb, or a verb used without an object, the gerundive stands in the neuter singular, impersonally, and English has to supply a subject from the context, or use “it is time to …”:

Nunc est bibendum, nunc pede līberō
pulsanda tellūs.
“Now we must drink, now the earth must be struck with a free foot.” (Horace)

Nunc quicquid est, quōcumque vestrae mentēs inclīnant atque sententiae, statuendum vōbīs ante noctem est.
“Now, whatever it is, whichever way your minds and opinions lean, you must decide before nightfall.” (Cicero)

In indirect statement the periphrastic takes the infinitive esse, which is often left out: Caesar statuit sibi Rhēnum esse trānseundum, “Caesar decided that he must cross the Rhine”; mātūrandum sibi exīstimāvit, “he thought he must make haste” (both Caesar).

A related idiom: with verbs like cūrō, dō and trādō the gerundive agrees with the object: with cūrō it means “to have something done”, with dō and trādō “to hand something over to be done”: complūrīs praetereā Hispalī faciendās cūrāvit, “in addition he had several built at Hispalis” (Caesar).

• Gerund: an English “…ing”, with the preposition its case suggests: “of …ing”, “by …ing”, “for …ing”.
• Gerundive with a noun (bellī gerendī): turn it round so the noun becomes the object of an “…ing”: “of waging war”, not “of war to be waged”.
• ad … or … causā: “to …”, “in order to …”.
• Gerundive + sum: “must”, “has to”, “had to”, “ought to”, with the dative as the subject if there is one: quid tibi vītandum “what you should avoid” (Seneca).
• Gerundive alone as an adjective: “to be …ed”, or an English adjective in “-able / -ible”: Multa ibi mīranda, multās formīdinēs patimur, “there we experienced many things to marvel at and many terrors” (Pliny).

• Translating every gerundive as “to be …ed”. That is right for the passive periphrastic, but in a purpose phrase it produces nonsense. In ad quiētem capiendam recubuit (Ritchie), Ulysses “lay down to rest”, not “for rest to be taken”.
• Confusing it with the future active participle. Both are verbal adjectives in -us, -a, -um, but the future participle has -ūr- and means “about to”, while the gerundive has -nd- and means “to be …ed”. Compare Peliās magnum sacrificium factūrus esset, “Pelias was about to hold a great sacrifice”, with quid faciendum esset, “what had to be done” (both Ritchie).
• Missing the dative of agent. A dative next to a gerundive + sum is usually the person who must act. Caesarī omnia ūnō tempore erant agenda is “Caesar had to do everything at once”, not “everything had to be done for Caesar”. But check the verb first: with a verb that itself takes a dative, the dative is its object, not the agent: Nūllī nocendum, “one must harm no one” (Phaedrus).
• Taking an -ndō or -ndum form for a gerund when it agrees with a noun. In in gerendō bellō the form agrees with bellō; it is a gerundive, though the English “in waging the war” is the same.