Particle or preposition?

I'm studying Spanish and I have some questions about the grammatical parallels in English.

Le gustan cocinar y hornear.

He likes to cook and (to) bake.

When an infinitive is used in Spanish, there's no ambiguity, because an infinitive has a unique spelling from the rest of the forms of the verb.

So my question is this:

I'm here to help.

Is to part of the infinitive help or is it a preposition?

In Spanish, this type of construction would use a preposition:

Estoy aquí para ayudar.

or

He yells to alleviate stress.

Él grita para aliviar el estrés.

You could rephrase these sentences to say "for alleviating..." or "for the alleviation of..." which is what really makes me want to say it's a preposition, but I'm still doubtful.

This obviously isn't a major issue but it's a thought that pops into my head a lot.

Solution 1:

The Spanish infinitive marker -Vr is part of the same sound unit as the verb stem it attaches to (it affects the placement of stress), and it can only appear after a verb stem, so it is classified as an affix (in this case a suffix).

English to is normally considered to be its own word (rather than an affix) because it is not all that exclusive about where it can appear w/r/t other words: it can come before a noun phrase, it can come at the end of a sentence, or it can come before a verb in its base form:

...to Rome.
...the door she went to.
...to walk.

English verbs have a base form which shows up after modal auxiliaries, and after to in forming the infinitive:

...will walk; ...can walk; etc.
...to walk.

Spanish has no special verb form corresponding the English base form, but the Spanish infinitive is a pretty close fit.

Note also that the English infinitive has more than one function. Just to name a couple:

• The infinitive is required as a complement after certain verbs: e.g., ...hope to walk.
• The infinitive may have purposive meaning: e.g., ...(in order) to walk.
• The infinitive may be used to refer to a verb phrase in the abstract: e.g., to suffer The Slings and Arrows of outrageous Fortune, Or to take Arms against a Sea of troubles

These functions tend to be translated by the Spanish infinitive, but there are some uses of the Spanish infinitive that are better translated with the English present participle (-ing form). But the English present participle itself is sometimes best translated with the Spanish infinitive, sometimes the Spanish present participle (-Vndo form), and sometimes with the Spanish simple present...

Solution 2:

Is ‘to’ a preposition or a particle? Well, in these examples it’s followed by verbs (cook, bake, help etc.) Prepositions are followed by nouns (prepositional phrases are made up of preposition + noun, in other words,) so we can conclude that ‘to’ is not a preposition here. Here are some examples of ‘to’ prepositional phrases as verb complements.

The trail led to the road.

He spoke to the crowd using a megaphone.

Count to ten before you open your eyes.

This is how prepositions are traditionally presented – as words that have NP complements. In a recent treatment of English grammar by Huddleston and Pullum, however, the scope of prepositions has been widened. In their reading, a preposition can itself take another prepositional phrase or even a subordinate clause as a complement. For example,

PP: He called out from behind the sofa.

SC: She went home after the concert had ended.

However, this widening of scope does not extend to verb complements like to-infinitivals. Here is what Huddleston and Pullum have to say about this case (from ‘A Student’s Introduction to English Grammar’ p. 205).

To-infinitivals are marked by the word to, which derives historically from the preposition to (note the strong similarity in meaning between I went to the doctor and I went to see the doctor) but long ago lost its prepositional properties. It is now unique: no other item has exactly the same grammatical properties. We take it to be a member of the subordinator category – a special marker for VPs of infinitival clauses.

There are some parallels between English and German here (e.g. ‘start to help’ = ‘anfangen zu hilfen’), but for instance Russian and some other Slavic languages are like Spanish with only the bare infinitive. Look farther afield to say Chinese and even the concept of ‘infinitive’ becomes meaningless. Minute comparisons like this aren’t particularly fruitful when learning languages, in my view.

Solution 3:

Of course "to" is a preposition, but by definition a preposition (prep) is used before a noun.If the meaning is clear the noun can be dropped, but then the lacking noun is self-evident. In English "to" is also used to indicate the infinitive, neglecting the few cases where a bare infinitive is used.

Now you could invent such terms as "infinitive-prep" or "infinitive indicator", but as we have already the term particle from Latin grammar I tend to see it best to talk of infinitive particle.