Is "en" a pronoun or preposition in "n’en pouvant plus"?

Question

The question is on en as occurring as highlighted in this excerpt from Voltaire's Candide.

Candide, tout stupéfait, ne démêlait pas encore trop bien comment il était un héros. Il s’avisa un beau jour de printemps de s’aller promener, marchant tout droit devant lui, croyant que c’était un privilège de l’espèce humaine, comme de l’espèce animale, de se servir de ses jambes à son plaisir. Il n’eut pas fait deux lieues que voilà quatre autres héros de six pieds qui l’atteignent, qui le lient, qui le mènent dans un cachot. On lui demanda juridiquement ce qu’il aimait le mieux d’être fustigé trente-six fois par tout le régiment, ou de recevoir à la fois douze balles de plomb dans la cervelle. Il eut beau dire que les volontés sont libres, et qu’il ne voulait ni l’un ni l’autre, il fallut faire un choix ; il se détermina, en vertu du don de Dieu qu’on nomme liberté, à passer trente-six fois par les baguettes ; il essuya deux promenades. Le régiment était composé de deux mille hommes ; cela lui composa quatre mille coups de baguette, qui, depuis la nuque du cou jusqu’au cul, lui découvrirent les muscles et les nerfs. Comme on allait procéder à la troisième course, Candide, n’en pouvant plus, demanda en grâce qu’on voulût bien avoir la bonté de lui casser la tête ; il obtint cette faveur ; on lui bande les yeux ; on le fait mettre à genoux.

Question

Which reading of en is correct? (If neither is, please let me know the way to read it.)

1. en is a pronoun referring to the foregoing situation or, if a definite reference is required, perhaps to course or coups de baguette. pouvant, a participle, modifies Candide. So we get "of-it-no-more-capable Candide."

2. en is a preposition setting up a gerund. We are not told what it is that Candide is incapable of. So we get "Candide, as (because) he was no more capable."

Background

Please kindly explain the general principles behind your answer so I may apply them to new situations.

Perhaps I should identify some issues which I think are contributing to my confusion.

• When should one use a participle alone vs. en + participle? For example, would an en placed before marchant or croyant (as highlighted) change the meaning or be ungrammatical? (General treatment like this has not really helped.)

• Will ne and en be in that order (i.e. n'en and not en ne) if en is a pronoun? And if en is a preposition?

Answer 1

Unfortunately I don't have enough reputation to leave a comment on your question so I'll post a short answer.

In this case, en is a pronoun referring to the punishment Candide is receiving (the coups de baguette).

To answer you other question, ne and en will always be in that order if en is a pronoun (I am 99% sure and can't think of any exceptions but please do correct me if I'm wrong).

You can recognise en as a pronoun by asking the question:

De quoi Candide n'en pouvait plus ?

The answer here is:

Candide n'en pouvait plus des coups de baguettes

So, now I know that en is a pronoun with as function COI (complément d'objet indirect).

If en is a preposition, it will introduce a complément de lieu, de manière, de temps ou de moyen,a complément de nom ou de l'adjectif or it can function as comme. Some examples:

Je vais partir en France. (It introduces a place)
Nous y allons en voiture. (It introduces a way (moyen) of transport)
Un bracelet en or. (It completes the noun bracelet)
Ils se sont quittés en bons amis. (You could replace en with comme)

I hope this helped you understand a bit better.

Answer 2

If you analyze the fragment “n'en pouvant plus” grammatically, en can only be a pronoun. There has to be a verb between the two parts of the negation n' and plus, so pouvant has to be analyzed as a verb form, not as an adjective. If en pouvant was a gerund, the negation would have to be placed inside: “en ne pouvant plus” (this is a valid sentence fragment, but it would normally be followed by a direct complement of the verb pouvant).

The pronoun en normally stands for a complement that starts with de (either the preposition or the beginning of a partitive article). However, you won't find an antecedent here, because n'en plus pouvoir is an idiom, meaning to be at one's limits, to not be able to take any more abuse. The verb phrase n'en plus pouvoir can only be used with this negation (plus). It is not possible to write “*Candide ne pouvait plus de …” (it might have been possible in Old French, but not in anything resembling modern French). It is possible to add a complement, however; that would be an indirect complement introduced by de.

Candide n'en pouvait plus.   Candide couldn't take it any more.
Candide n'en pouvait plus d'être battu.   Candide couldn't take any more beating.

Voltaire's sentence “Candide, n’en pouvant plus, demanda en grâce qu’on voulût bien avoir la bonté de lui casser la tête” could be rephrased as “Candide, à bout de forces, demanda …”. If the thing that Candide could not stand was mentioned explicitly, the sentence could be phrased as “Candide, n'en pouvant plus d'être battu, demanda …” or “Candide, ne supportant plus d'être battu, demanda …”. The complement is a phrase built on a present participle, which qualifies the noun that precedes it (Candide). This complement could be reworded as a subordinate clause with a relative pronoun: “Candide, qui était à bout de forces, demanda …”.

A gerund would be grammatically possible here, though the normal position would be after the verb — a gerund qualifies a verb, not a noun. However doesn't fit semantically in this sentence. An example of a sentence with a gerund would be “Candide demanda en gémissant qu'on arrête de le battre.”