On Non-Finite Verbs, Chapter 2: The Basic Infinitive

How much is there to write about the basic infinitive? A surprising lot, really.

The English Infinitive

The English infinitive does happen to be the dictionary form, and is basically the stem of the verb. It has a morphological quirk, in that some auxiliaries lack an infinitive. Such lacks do happen for individual non-auxiliary verbs in some languages, e.g. Finnish lacks one for one of its verbs for 'to itch'.

What does the infinitive do? The typical response would perhaps be 'serves as the subordinate verb for another verb', but this misses several other uses, and also conflates several rather distinct uses into a single category.

Let's start out with the subordinate verb, though.

he will go
he wants to go

Already here we find a nice split - infinitives with and without 'to'. This is mainly governed by the finite verb (a certain class called 'modal auxiliaries' do not take them - but this class is not strictly described by its name - some modal auxiliaries have no modal meaning, some non-modal auxiliaries do, etc.

We do also find e.g. a modal use of the verb 'have' taking to+inf: I have to go.

A different verbal construction where the infinitive is featured is this:

I saw her dance the jig
She listened to him play the cembalo

These don't convey the same thing as a subclause; it's not "I saw when she danced the jig" or "I saw that she danced the jig". More like, "I saw the event consisting of her dancing the jig", having the agent of the subordinate verb be both the object of the main verb and subject of the subordinate one.

And further this:

He wanted us to go away
We asked him to sing a song

These four previous examples differ from earlier ones in having a different agent of the infinitive than of the main verb; this agent is not marked as a canonical subject, however, but by an oblique case. It is not very unusual in languages for infinitives not to be able to take canonical subjects, but rather to take some form of oblique agent.

Infinitives can also act as nouns that are a stand-in for the verb phrase in statements about a verb phrase:

to paint the house is quite the chore
to win is fun
to err is human

In English, both 'to paint' and the participle/gerund 'painting' can serve in this position. These can take oblique subjects, 'for us to pay these debts will take years', 'her singing at the opera tonight will be spectacular'.

The infinitive can also work as an attribute of a noun:

the will to live
the desire to seek revenge
failure to comply
a sight to see
the first woman to serve as judge
the only man to admit to being wrong

Some of these seem to be almost like relative subclauses! Further, sometimes they are passive (a sight to see), sometimes active (the first woman to serve as a judge).

Arguably, English infinitives can mark certain one tense distinction and voice - 'to see' , 'to have seen', 'to be seen', 'to have been seen'. They can also be negated, and depending on your stance, either with the 'not' before or after 'to'. Some positions seem not to license the perfect tense:

*I saw him have hit the jackpot
I saw him be beaten by a gangster
*I saw him have been beaten by a gangster

 There are more ways it is used in English, but I will introduce them later on in this post.

The Swedish Infinitive

The English infinitive has a very similar cousin in Swedish. It has even undergone a similar development after the languages diverged, where both acquired a preposition that marked them, and this preposition indeed splits the auxiliaries mainly along very similar lines. Don't quote me on this, but I suspect Swedish has more 'subtle collocations', here, where some combinations of auxiliary and main verb may deviate from the more regular pattern for an auxiliary.

 All the syntactical details above hold for Swedish as well, but here we get a bit of a deviation: in Swedish, infinitives are more often attributes of nouns than they are in English. Especially in cases where they are not subclause-like in meaning.

konsten att förföra
"the art to seduce"
~ the art of seduction

This is significantly more common in Swedish than English, with constructions like viljan att leva (the will to live), en baddare att sjunga (a whiz of singing), etc being fairly frequent in texts.

 Swedish also likes having infinitives as attributes of adjectives:

han är bra att laga mat
he is good to cook food

hon är rolig att tala med
she is fun to talk to

vi är svåra att slå 
we are hard to beat

Obviously, two of these work in English too! But the first example is weird. English prefers either 'he cooks well', or 'he is good at cooking'. 

Other than these differences, the main differences appear in some raising-structures. We will look more into such things later.

Morphologically though, Swedish differs from English: the infinitive is a particular inflected form of the verb. The suffix that marks the infinitive is -a, but this may be suppressed if the stem ends in a vowel. The imperative happens to coincide with the stem for conjugations I and III, but for II and IV, the imperative does not coincide with the infinitive. C.f. hoppa <> hoppa ('to jump, to hop'); springa <> spring ('to run'). Thus, in Swedish, -a is (sometimes) a morpheme marking the infinitive, sometimes -a is supressed.

The Swedish infinitive can be negated - with the negation going between 'att' and the infinitive (or before the infinitive if 'att' is absent). It can also take the passive -s suffix, or use any of the other passive constructions. It can also be in the perfect ~tense, but this is also restricted in ways very similar to English.

In both English and Swedish, infinitives can sometimes have "non-anaphoric" reflexives: to know oneself is important; att känna sina gränser är viktigt (to know one's own limits is important).

The Finnish Infinitive

Finnish has an awkward nomenclature, including several numbered infinitives. However, the infinitive I is the most similar to the above forms in use: it is used after modal auxiliaries and after some other auxiliaries. It is not used in constructions such as 'I heard him sing', where a participle is used instead. Even for the infinitive I, Finnish does have an analogous formation to the English 'to'-infinitive: -kse.

onnistua -> onnistuakse-

This is not used quite as frequently as the English to-forms - it is for instance not used as a subject of a statement about the verb, or as the subordinate verb of an auxiliary or such. Oftentimes, it corresponds to the English 'so as to [inf]', or 'for to [inf]', but will sometimes correspond to just a 'to [inf]' construction. However! Sometimes this will correspond to infinitive IV instead, so ... this will require further investigation in post focusing on the Finnish system.

 

The -kse-infinitive further requires a possessive suffix corresponding to the subject: onnistuakseni (for me to succeed), onnistuaksesi (for you to succeed), etc.

 

Onnistuakseni tarvitsen apua -> for me to succeed, I need help

Lui-n kirja-n oppia-kse-ni musiikkiteoria-n alkee-t.
read-I book-acc learn-kse-my musictheory's foundation-s.

 

Comparing and contrasting the Finnish non-finite landscape to the English system will be done in a later post.

 

As an attribute, the basic infinitive I is similar to Swedish with regards to things like 'the skill to cook good food' (kyky laittaa hyvää ruokaa), but the infinitive I cannot be used in an active relative subclause  type of way; however, as a passive subclause it can work: 'hyvä kirja lukea lomalla', although a different form might be more idiomatic (luettavaksi or lukemaksi, the first a passive present participle, the second an infinitive IV, both in the translative case). Here, certain adjectives and quantifiers seem to license the use of an infinitive as an attribute or as a complement of the copula. The -kse-infinitive can also be used as an attribute expressing for whom something is for doing something to: eväitä syödäksesi: snacks-part eat-inf-kse-yours: snacks for you to eat. However, the passive present participle is more often used for this.

 

As a complement of the copula, the Finnish infinitive I further signifies 'almost did', often as a near-miss accident. "Olin kompastua" - I was (about to) stumble.

 

Finnish does not use the infinitive I for construction such as 'I saw her dance'. Instead it uses the active present participle in the genitive, thus a bit like 'I saw her dancing', but actually 'I saw her dancing's'.

The infinitive cannot be passive; any passivization would instead use some kind of passive participle. The infinitive cannot be negated using the regular 'ei-' negation strategy; instead, olla +mAttA, i.e. essentially 'be without [verb]ing' is used instead.

 

The infinitive can  take the perfect tense, but this seems very rare to me - I do find an example 'olla syönyt ateria' - to have eaten a meal. Some case shenanigans actually feel more natural to me: 'To have run', for instance, could come out as 'olla juoksuneena', essentially 'to be [in the role of] having run'. The 'olla syönyt' construction does work as subordinate of other verbs, but feels odd when used more nominally.

The Portuguese Infinitive

Famously, Portuguese infinitives can inflect for person. I am not an expert on the syntax of the infinitive in Portuguese, so this will be left here for now as a sort of heads-up.

A tabular representation of some differences of the basic infinitive

This table will grow over time, with all kinds of subcases and differences, and of course several forms per language. I figure colour-coding will also help seeing what's going on once it starts growing unwieldy.

Property	English	Swedish	Finnish I	Portuguese
Citation form	✓	✓	✓	✓
Infinitive marker (like to, att)	✓ (sometimes)	✓ (sometimes)	✗ (infinitive II is structurally similar to such a marker)	✗
Dedicated infinitive ending	✗	✓	✓	✓
Person agreement	✗	✗	✗ (mandatory on infinitive II)	✓
Voice distinctions	✓	✓	✓/✗*	✓
Tense / aspect distinctions	✓ (limited)	✓ (limited)	(rare)	✓
Regular negation	✓	✓	✗	✓

* The Finnish passive is really more of an indefinite person; however,  Finnish has a significant bunch of valency- and transitivity-altering derivative suffixes, which do permit infinitives. IMHO, saying that the Finnish infinitive can't be passive is thus marginally misleading, but 'traditionally' correct.

Summary:

We've seen some differences between infinitives in four languages of Europe; the "basic" infinitives of these languages all have a core of shared uses:

• A sort of noun-like head of a verb phrase
• A verb that is subordinated under another verb in some way.

 However, we find differences as well: the use of markers like to/att, the use of infinitives as attributes, their syntactic distribution in general, and how the roles that one language's infinitive takes is distributed onto other forms in other languages.

Turns out the infinitive is not so much a single thing as a complex of things.