Can someone parse or explain this to me:

Dá mhéid é an mian gurb ea is mó an gníomh

I know what it means (The greater the desire was, the greater the deed), but it is difficult to parse in terms of V p P s and S.

ea: should be a subpredicate.

Is mó an gníomh: all this is the predicate?

Or is there in implied relative particle before the "is"?

Or taking: is mó an gníomh - is this VPS?, a copula sentence nested in the wider sentence.

Dá mhéid é an mian: An mian - S, é = p, Dá mhéid = predicate, or something that stands for the predicate.

So then it is PpS+gurb+P+(implied relative)+VPS?

Or is the implied relative nominative to the rest of the sentence, so that "is mó an gníómh" is VP only?

And the "gur" in there - does it connect to some kind of elided verb that is not expressed? If so, what verb?

Is the implied verb "is amhlaidh gur"?

So there are three nested copulas here? Is amhlaidh gur dá mhéid é an mian gurb ea is mó an gníomh?

And why is there no sub-pronoun before "an gníomh"?

It is possible to just accept idiom as it is, but as you can see these three nested copulas are hard to parse and pick apart.

Is mó an gníomh: straightforwardly VPS. Subject = an gníomh, predicate = mó.

Then this VPS is nested within a larger copula of which it is the subject.

XXX gurb ea XXX : P gurb p S (where S is actually VPS itself)

Dá mhéid é an mian is thus, taken as a whole, the predicate of the larger sentence, while itself being resolved as a copula in itself, of the form PsS, where dá mhéid is the predicate and an mian is the subject.

So:

PsS gurb ea VPS>>>P gurb p S.

And then the question still remains, why no subpredicate in "is mó an gníomh"?

According to teanglann.ie, ‘dá’ is a compound of the preposition ‘de’ and the particle ‘a’, which ‘a’ is used with abstract nouns denoting degree. Both words seem to have similar – although apparently not the same – usages.

Here is a basic sentence that uses ‘dá’ (from teanglann.ie): Dá ghéire an scian ní ghearrfaidh sí iad. (Sharp as the knife is it will not cut them.) The sentence consists of two clauses. The first clause (Dá ghéire an scian) could possibly be considered an adverbial clause, with the second clause (ní ghearrfaidh sí iad) being considered the main clause. (Although, if so, one might think there should be a comma directly after the first clause.)

Therefore, you might expect ‘The greater the desire the greater the deed’ to translate to ‘Dá mhéid an mian is mó an gníomh’.

But for your sentence (Dá mhéid é an mian gurb ea is mó an gníomh), my guess is that ‘dá’ has somehow been reinterpreted as a form of the copula.

So maybe ‘méid’ is the predicate of the outermost clause, ‘é’ is the sub-subject, and the rest of the sentence (‘mian gurb ea is mó an gníomh’) is the subject. The subject could then be broken down into the noun ‘mian’ and the adjectival clause ‘gurb ea is mó an gníomh’. Although I'm not sure how you would further parse this adjectival clause.

Focloir.ie gives a few sample sentences that contain the components ‘dá mhéad’ and ‘is ea’ to express what in English would be called comparative correlative sentences e.g. ‘The more the merrier’. (See https://en.wiktionary.org/wiki/the#Etymology_2)

• Dá mhéad é is ea is fearr. (The bigger the better.)
• Dá mhéad a chuala mé is ea is mó buaireamh a tháinig orm. (The more I heard the more concerned I became.)
• Dá mhéad an aclaíocht is ea is lú an strus.
• Dá mhéad a dhéanfaidh na hoibrithe deonacha is ea is lú obair a bheidh le déanamh ag an gcuid eile again.
• Dá mhéad airgead a fhaighim is ea is mó a bhíonn uaim. (The more money I get the more I want.)
• Dá mhéad a fheiceann sí de is ea is mó a cion air. (The more she sees of him the more she likes him.)
• Dá mhéad í an deifir is ea is mó an mhoill (More haste less speed.)

(Only the final example above has what seems to be a sub-subject.)


In the following sentences (also from focloir.ie), ‘is ea’ has been replaced by ‘is amhlaidh’.

• Dá mhéad duine a bheidh ann is amhlaidh is fearr é. (The more the merrier.)
• Dá mhéad é is amhlaidh is fearr é. (The more the merrier.)
• Dá mhéad an scata is amhlaidh is lú an baol. (There's safety in numbers.)

I'm not sure how the rationalise the use of 'is ea' and 'is amhlaidh' in the above sentences.

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Now, your sentence (Dá mhéid é an mian gurb ea is mó an gníomh) seems to be similar in style to the above sentences, except that ‘is ea’ has – for whatever reason – been replaced by ‘gurb ea’.

Dá mhéid é an mian gurb ea is mó an gníomh

Ea is (sub)predicate, a resumptive pronoun for "dá mhéad é an mian" (which is the main predicate. it is made absolute, so grammatically not really part of the sentence).
It is the same sentence structure as "Fear is ea an múinteoir"
P is p S

it is based on a hypothetical "normal" sentence: Is dá mhéid é an mian is mó an gníomh (Is fear é an múinteoir)

gurb ea - usually it is is ea, so this whole sentence is a dependent clause. (... that the greater the desire ...)

is mó an ghníomh is subject as a whole though itself a (relative) clause: "is greater the deed" Its antecedent is missing.
(inside this clause mó is predicate, an gníomh subject)

dá mhéid é an mian - lit. "of its greatness/amount it the desire" figuratively: "by its amount of the desire". (de = by, compare: de trí phunt = by three pounds)
The pronoun é ("it", a subsubject) shows that this phrase is kind of a copula clause itself (an mian subject, dá mhéid predicate).


So: P gurb p S -> [PsS] gurb p [is P S]

Thank you both, and as Labhrás shows it is a copula sentence the subject and predicate of which are both in themselves copula clauses.

Is mó an gníomh - there is no sub-pronoun here (I'm unsure whether it would be VPsS or VPpS if you put a pronoun in, or if it really matters).

Is breá í an fhoighne - there is a pronoun here. I think this is VPsS, with í the sub-subject.

So my conclusion is that there is a sub-subject between an adjectival predicate and the subject, but not if the adjectival predicate is a comparative????

Yes. There is usually never a sub-subject in comparative copula sentences.

There is said to be a difference whether you use a sub-subject or not with basic forms of adjectives:
Is geal é an solas. (= That specific light is bright)
vs. Is geal an solas. (= Light in general is bright)