Nobilitas sine liberalitate et constantia parum valet.

The subject is nobilitas.

It is a singular noun, so the verb is singular too: valet = it is strong / it is worth much / it avails.

Latin verbs agree with their subjects in number and person, just as English does:

• nobilitas valet = nobility is of little value / avails little
• if the subject were plural, the verb would be plural too

Nobilitas is nominative singular, which is the normal case for the subject of a sentence.

It is a third-declension noun. Its dictionary form is nobilitas, nobilitatis.

So in this sentence:

• nobilitas = subject, nominative singular

They are in the ablative because they follow the preposition sine, which means without.

Sine regularly takes the ablative in Latin. So:

• sine liberalitate = without generosity
• sine constantia = without steadfastness / firmness

This is something Latin learners simply have to memorize with the preposition:

• sine + ablative

It applies to both.

Latin often uses one preposition with the first noun and lets it govern the second noun as well when they are linked by et:

• sine liberalitate et constantia = without generosity and steadfastness

In fuller English, you could think:

• without generosity and without steadfastness

But Latin does not need to repeat sine.

Here parum is an adverb, meaning too little, not much, or only slightly.

It modifies the verb valet:

• parum valet = is worth little, avails little, has little value

This is important because English learners may expect an adjective, but Latin uses the adverb parum with the verb.

Because parum is the adverb, while parvus is an adjective.

• parvus means small and would describe a noun
• parum means little / not much and here it modifies the verb valet

So Latin is not saying that nobility is small. It is saying that nobility counts for little or has little force/value.

Valet comes from valeo, valere, whose basic idea is to be strong or to be well.

Depending on context, it can mean:

• is strong
• is effective
• has value
• avails

In this sentence, the sense is not physical strength but worth or effectiveness:

• parum valet = has little value / counts for little

Nobilitas can mean nobility, but that English word has more than one sense, just as the Latin word can.

Possible shades of meaning include:

• noble birth
• high social rank
• the nobility as a class
• nobleness in a more abstract sense, depending on context

In this sentence, the idea is probably something like high birth or noble status. The point is that such status counts for little if it lacks liberalitas and constantia.

Classical Latin has no articles like English the and a/an.

So nobilitas can mean:

• nobility
• the nobility
• sometimes even a noble status, depending on context

Likewise:

• liberalitate = generosity
• constantia = steadfastness

English has to choose whether to add an article, but Latin does not.

Latin word order is much freer than English word order because Latin uses endings to show grammatical function.

In this sentence:

• nobilitas is the subject because it is nominative
• liberalitate and constantia are ablative because they follow sine
• valet is the verb

That means Latin can arrange the words for style or emphasis. The order here is very natural and elegant:

• Nobilitas — topic/subject first
• sine liberalitate et constantia — the important condition in the middle
• parum valet — the judgment at the end

English relies much more heavily on word order to show who is doing what.

Here is a quick parsing:

• Nobilitas

  • noun
  • nominative singular
  • feminine
  • third declension
  • subject

• sine

  • preposition
  • takes the ablative
  • means without

• liberalitate

  • noun
  • ablative singular
  • feminine
  • third declension
  • object of sine

• et

  • coordinating conjunction
  • means and

• constantia

  • noun
  • ablative singular
  • feminine
  • first declension
  • also governed by sine

• parum

  • adverb
  • means little / not much / too little

• valet

  • verb
  • third person singular
  • present indicative active
  • from valeo, valere

Yes. Meaning does not determine declension.

Constantia is a first-declension noun:

• nominative singular: constantia
• ablative singular: constantia

That can look surprising to English speakers because the nominative and ablative singular are the same in the first declension. But that is perfectly normal.

Its case here is identified by syntax:

• after sine, it must be ablative

Because they belong to different declensions.

• liberalitas, liberalitatis is third declension

  • ablative singular: liberalitate

• constantia, constantiae is first declension

  • ablative singular: constantia

So they are in the same case, but they show that case with different endings because they come from different declension patterns.

Yes. A very literal translation might sound awkward in English.

Depending on style, you might render parum valet as:

• is of little value
• counts for little
• avails little
• matters little

All of these reflect the idea that nobility, by itself, does not amount to much if it lacks the virtues named after sine.