Avus dicit gravitatem sine tristitia servari posse, sed levitatem sine modo saepe nocere.

The main clause is Avus dicit = Grandfather says.

After dicit, Latin uses indirect statement. In this sentence, there are two indirect statements:

• gravitatem sine tristitia servari posse
• sed levitatem sine modo saepe nocere

So the structure is basically:

• Grandfather says [that seriousness can be preserved without sadness], but [that lightness without moderation often harms].

The verb dicit governs both parts.

Because in a Latin indirect statement, the subject of the infinitive is normally put in the accusative.

So here:

• gravitatem ... servari posse = that seriousness can be preserved
• levitatem ... nocere = that lightness harms

Even though gravitatem and levitatem are the logical subjects of their clauses, they appear in the accusative because of this construction.

This is one of the most important features of Latin syntax after verbs like dicit, putat, scit, audit, and so on.

Because servari posse means to be able to be preserved / maintained.

It is made of:

• servari = present passive infinitive of servo (to be preserved, to be maintained)
• posse = infinitive of possum (to be able)

Together they mean:

• servari posse = can be maintained / is able to be preserved

So gravitatem sine tristitia servari posse literally means something like:

• that seriousness can be preserved without sadness

Because gravitas is not doing the action; it is receiving it.

Latin is expressing the idea:

• seriousness can be maintained not
• seriousness can maintain something

So the passive infinitive servari is exactly what we would expect.

Because the meaning is different.

The first half says:

• gravitatem ... servari posse = seriousness can be maintained

The second half says:

• levitatem sine modo saepe nocere = lightness without moderation often harms

This is not about ability; it is a direct statement of what happens. So posse is not needed there.

Sine takes the ablative.

So:

• sine tristitia = without sadness
• sine modo = without measure / without moderation

That is why tristitia and modo are ablative singular.

Modus has a basic sense of measure, limit, or proper bounds.

So sine modo literally means:

• without measure
• without limit

In smoother English, that often becomes:

• without moderation
• without restraint

So the idea is not merely without a method, but without self-control or proper limits.

No. Here they are abstract moral or personal qualities, not physical weight.

• gravitas often means seriousness, dignity, weight of character
• levitas often means lightness, but in moral or social contexts it can suggest frivolity, flightiness, or sometimes a more neutral playfulness

So the contrast is something like:

• seriousness without gloom versus
• lightness without moderation

This is a very Roman-style contrast in values.

Yes, exactly.

The sentence is making a distinction:

• gravitas = seriousness, dignity
• tristitia = sadness, gloom

So it says that true seriousness does not require gloominess. A person can be serious and dignified without being sad or severe in a joyless way.

That contrast is an important part of the sentence’s meaning.

Good question. Levitatem is not the direct object of nocere.

Instead, it is the subject accusative of the indirect statement:

• levitatem ... nocere = that lightness harms

The verb noceo, nocere normally takes a dative for the person or thing harmed:

• alicui nocere = to harm someone

But here no dative is expressed. The sentence simply says that unrestrained lightness is harmful or does harm, without naming a specific victim.

You can think of it that way, yes.

Since nocere often means to harm someone/something, Latin could have added a dative, such as:

• alicui nocere = to harm someone

But the author leaves it general:

• saepe nocere = often to do harm / often to be harmful

This is perfectly natural.

Because Latin often omits a repeated governing verb when it is easy to understand.

So:

• Avus dicit gravitatem sine tristitia servari posse, sed levitatem sine modo saepe nocere

means:

• Grandfather says that seriousness can be preserved without sadness, but that lightness without moderation often harms

The second that-clause is still dependent on dicit, even though dicit is only written once.

Because Latin word order is flexible.

Saepe modifies the idea of nocere:

• often harms

Its position before the infinitive is natural and gives the adverb a little prominence. Latin often places adverbs where they best fit the rhythm or emphasis of the sentence, rather than following a fixed English-style order.

Both infinitives are present infinitives:

• servari
• posse
• nocere

In indirect statement, the present infinitive usually shows action at the same time as the main verb, or expresses a general truth.

Here the sentence is really expressing a general truth:

• seriousness can be maintained without sadness
• lightness without moderation often harms

So the present infinitive fits very well.

Yes. More literally, it is:

• that seriousness is able to be preserved without sadness

But in normal English, we would usually say:

• that seriousness can be preserved without sadness
• or that dignity can be maintained without gloom

The Latin is compact, but the idea is straightforward once you see the indirect statement.

Yes. Avus is the nominative singular subject of dicit:

• Avus = grandfather
• dicit = says

So the sentence begins very simply:

• Grandfather says ...

Everything after that is what he says.