Illa autem fabula non eiusdem generis est; tota enim natura eius diversa est.

Illa is the feminine nominative singular form of ille, illa, illud.

Here it agrees with fabula, which is also feminine nominative singular. So illa fabula means that story.

A learner may expect Latin to always put a demonstrative right next to its noun, but Latin is freer with word order. Here they are next to each other, which makes the connection easy:

• illa fabula = that story

Autem usually means however, but, or on the other hand.

In Latin, words like autem commonly appear in second position in their clause. So instead of beginning the sentence, Latin often puts one word first and then places autem immediately after it.

So:

• Illa autem fabula = That story, however, ...

This is a very common Latin pattern. It may feel strange to an English speaker, but it is normal Latin word order.

Eiusdem generis is genitive singular.

It means:

• of the same kind
• of the same sort

The forms are:

• eiusdem = genitive singular of idem, eadem, idem (the same)
• generis = genitive singular of genus (kind, type, class)

So literally:

• non eiusdem generis est = it is not of the same kind

Latin often uses the genitive with sum to describe kind, category, or value.

So instead of saying something like it is the same kind, Latin often says:

• it is of the same kind

That is why you get:

• eiusdem generis est

This is a standard idiom. English sometimes does something similar with of:

• It is of the same kind
• It is not of the same class

So generis is genitive because Latin is expressing classification.

Non negates the statement that follows.

Here it negates the whole idea:

• non eiusdem generis est = is not of the same kind

Latin often places non directly before the part being denied. In this sentence, it naturally comes before the predicate expression.

Enim usually means for, indeed, or you see. It gives a reason or explanation.

Here the second clause explains the first:

• That story, however, is not of the same kind; for its whole nature is different.

Like autem, enim tends to appear in second position in its clause. So Latin says:

• tota enim natura eius diversa est

rather than putting enim first.

This second-position habit is very common with particles like autem and enim.

Tota natura eius means its whole nature or its entire character.

Breaking it down:

• tota = whole, entire
• natura = nature, character, essential quality
• eius = of it, its

So the phrase is saying that the story is different not just in one detail, but in its entire nature.

In good English, nature here often means something like:

• character
• essential quality
• basic type

Eius most naturally refers back to fabula.

So:

• natura eius = its nature
• that is, the nature of that story

Because fabula is a feminine noun, an English speaker might expect a specifically feminine form meaning her or its. But eius is the regular genitive singular form for is, ea, id, and it can mean:

• his
• her
• its
• of him / of her / of it

The context tells you which one is meant. Here, its is the natural translation.

Both words agree with natura, which is feminine singular nominative.

So:

• tota natura = the whole nature
• natura diversa est = the nature is different

Agreement in Latin means adjectives match their noun in:

• gender
• number
• case

Since natura is feminine singular nominative, both tota and diversa are feminine singular nominative too.

Latin often uses an adjective with sum where English might use either:

• an adjective: is different
• or a verb: differs

So:

• diversa est literally = is different

This is completely normal Latin. It describes the subject by means of a predicate adjective:

• natura ... diversa est = the nature ... is different

Latin word order is much freer because the endings show how words relate to each other.

English depends heavily on position:

• subject + verb + object

Latin can move words around more easily for emphasis, contrast, or style. In this sentence, the arrangement helps highlight certain ideas:

• Illa autem fabula: introduces that story with a contrast
• non eiusdem generis est: gives the main claim
• tota enim natura eius diversa est: explains why

A very literal rearrangement into more English-like order would be:

• Illa fabula autem non est eiusdem generis; natura enim eius tota diversa est.

But the original Latin is more elegant and emphasizes the important words well.

Yes, Latin can sometimes omit a form of sum when it is easily understood, especially in certain styles. But here est is expressed in both clauses:

• non eiusdem generis est
• diversa est

Including est makes both clauses clear and balanced. It also gives the sentence a neat parallel structure:

• it is not of the same kind
• its whole nature is different

So while omission is sometimes possible in Latin, here the repeated est is perfectly natural and stylistically effective.

Yes. The first clause gives the claim in a fairly formal, classificatory way:

• it is not of the same kind

The second clause strengthens and explains that claim:

• for its whole nature is different

So the sentence moves from:

1. classification — it does not belong to the same category
2. explanation — because its entire character is different

That makes the statement stronger than simply saying it is different once. The speaker is saying that the difference is deep and essential, not minor.