Latin from scratch #20.39: The morphology and syntax of infinitives

In the thirty-ninth class of the Latin from Scratch course, we’ll study the morphology and the syntax of infinitives, all of which is more complex than in English, because we have six infinitives and they can appear in structures foreign to English.

I explain everything in the following video (⏳ 23m 42s ⌛):

Morphology

English is considered to have only one infinitive (e.g. “to go”), whereas in Latin we have six different infinitives: present active and passive, perfect active and passive, and future active and passive. The most frequent ones are both present infinitives and perfect active.

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Present infinitives

The active present infinitive is formed with the following morphemes:

1. present stem
2. ĕ (3rd conjugation only)
3. re

Thus, we have the following examples: amāre, monēre, ducĕre, capĕre, audīre.

The passive present infinitive is formed in the following way:

1. present stem
2. ri / i
   • ri in the 1st, 2nd, 4th conjugations
   • i in the 3rd and mixed conjugations

So we end up with amāri, monēri, duci, capi, audīri.

Perfect infinitives

The active perfect infinitive is formed by joining the following morphemes:

1. perfect stem
2. isse

So we have amavisse, monuisse, duxisse, cepisse, audivisse.

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The passive perfect infinitive, on the other hand, is periphrastic:

1. accusative of the perfect participle (agreeing in gender and number with the subject)
2. present infinitive of sum: esse (occasionally fuisse may appear)

The result is amatum, ‑am, ‑um / amatos, ‑as, ‑a esse (or fuisse), etc.

Future infinitives

The active future infinitive is periphrastic as well:

1. accusative of the active future participle (agreeing in gender and number with the subject)
2. present infinitive of sum: esse (occasionally fuisse may appear)

So amaturum, ‑am, ‑um / amaturos, ‑as, ‑a esse (or fuisse), etc.

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The passive future infinitive can be expressed in two different ways. The most frequent one is as follows:

1. accusative of the passive future participle (agreeing in gender and number with the subject)
2. present infinitive of sum: esse (occasionally fuisse may appear)

So we would have amandum, ‑am, ‑um / amandos, ‑as, ‑a esse (or fuisse), etc.

The other way is also periphrastic:

1. supine (in the accusative)
2. iri (passive present infinitive of eo)

So it would be amatum iri, etc.

Syntax

The syntax of the infinitives in Latin can be explained in at least a couple of ways, both of which have their own important points. One way to classify infinitives is nominal vs. verbal function; the other way is agreeing vs. non-agreeing.

Nominal vs. verbal function

Both of them may have all kinds of complements like any other verb. The main difference is whether they are translated as a regular English infinitive or more needs to be done.

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Most of the times, nominal infinitives are present infinitives and are translated as infinitives. They are either the direct object or the subject of the main verb:

• Direct object being dependent on frequent verbs such as possum ‘can’, debeo ‘must’, soleo ‘be wont’, coepi ‘start’, constituo ‘decide’, decerno ‘decide’…
• Subject being dependent on expressions with sum or impersonal verbs such as decet ‘it is appropriate’, licet ‘it is permitted’, oportet ‘it is necessary’…

The most important, however, are the verbal infinitives, which create a noun subordinate clause. They have the following features:

• their verb is an infinitive
• the subject is in the accusative (without preposition); also the attribute, if there is one
• there is no conjunction in Latin joining the subordinate and superordinate clauses
• English does have infinitive clauses, but they don’t work to the same extent, so often we need to conjugate the Latin infinitive in order to express the relative time

There is no point in learning by heart a table with correspondences, which is why understanding the relative time is so important and useful. Taking all of this into account, we will soon practice to understand completely the whole thing.

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If the subject is the same both for the superordinate clause and the infinitive clause, the infinitive may be translated as infinitive in English:

Illa missam esse a patre dixit.

She said that she had been sent by her father.

She said to have been sent by her father.

Infinitive clauses can also work as direct object or subject of the superordinate clause, whose verb can be of many types. However, most frequently they work as direct object being dependent on verbs of talking (“say”, “speak”, “command”…), thinking (“understand”, “think”, “believe”, “consider”…) and senses (“see”, “hear”…).

Agreeing and non-agreeing

All this having been said, the most practical thing to do is just considering whether the infinitive is agreeing or non-agreeing. By agreeing we mean that the subject for the superordinate verb and the infinitive is the same (i.e. they agree):

• agreeing: the subject of the superordinate verb and of the infinitive is the same
• non-agreeing: the subject of both verbs is different

Agreeing infinitives, regardless of whether they are nominal or verbal, can usually be translated as an infinitive (simple or compound), whereas non-agreeing infinitives should be converted to express the appropriate relative time.

Infinitives are more complex than it might seem at first, so we need to really practice with them to understand completely what they are about.

Next: The morphology and syntax of infinitives →