Tempodivalse:Grammatical cases have a bad rap, but there is nothing intrinsically challenging about them. The problem arises with irregular/unpredictable inflections - e.g., in Russian, you have to memorise a set of new endings for each declension (there are very very many). And with some verbs you have to (arbitrarily) use a non-accusative to mark the direct object.

I agree that cases per se are not challenging, however it is quite challenging to know (and above all to predict) when to use which case. Let me give some examples:

Mi helpis lin.
Eo: accusative.
Fr: accusative (Je l'ai aidé.).
De: dative (Ich half ihm.)
Es: dative = CI (Le ayudé.)
Ru[1]: dative (Я помог ему.)

Mi nomas vin amiko.
Eo: nominative
De: accusative (Ich nenne dich einen Freund.)
Ru: instrumentalis, I guess. No idea thought.

Li(1) ŝatas katojn(2).
Eo: (1) nominative; (2) accusative
De: (1) nominative; (2) accusative (Er mag Katzen.)
Es: (1) dative = CI; (2) nominative (Le gustan los gatos.)
Ru: (1) dative; (2) nominative (Eму нравятся коты.?????)

Even worse when we get to causatives of transitive verbs:
La bebo manĝas kaĉon.
Mi manĝigas la bebon kun kaĉo.
Mi manĝigas kaĉon al la bebo.

When we are talking about a patient (i.e. something or someone directly suffering from an action) it is quite obvious to choose the accusative. In every other case it is not. As in any natural language we have to learn by heart which case or which preposition each verb requires. This is the "bad rap".

I personally looked up "ŝati" many, many times when I started with Esperanto, because I simply couldn't remember if it followed the model of German "mögen" or Spanish "gustar".

And then we have the accusative of measure, the accusative of time and the accusative of direction. Even adverbial accusatives.

Cases just add a completely opaque layer between thematic roles and their representation (or realisation). I don't understand why Esperanto, being artificially created, uses such an obscure mechanism. Why not, for instance, mark thematic relations directly and cut out the cases?

An even more hopelessly complex area is the definite article la - even experienced Esperantists vary in their usage of it.

Quoted for truth.

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[1] Tempodivalse: Please correct my Russian examples. My Russian is more than rusty.

And then we have the accusative of measure, the accusative of time and the accusative of direction. Even adverbial accusatives.

So maybe it's not accustaive but just rolfinaĵo -n.

Cases just add a completely opaque layer between thematic roles and their representation (or realisation). I don't understand why Esperanto, being artificially created, uses such an obscure mechanism. Why not, for instance, mark thematic relations directly and cut out the cases?

Could you give some examples? How to mark thematic relations directly?

nornen:
Mi manĝigas la bebon kun kaĉo.

Wouldn't it be more correct to use the preposition per in this sentence? Mi mangxigas lin per kacxo.
I think all your Russian examples are correct.

nakymatonmies:

nornen:
Mi manĝigas la bebon kun kaĉo.

Wouldn't it be more correct to use the preposition per in this sentence? Mi mangxigas lin per kacxo.
I think all your Russian examples are correct.

Yes, per kaĉo.

@nornen, a lot of the differences between languages you pointed out also are applicable to prepositions (prepositional cases), not just the accusative case.

Fortunately, in Esperanto, you can often express yourself in a variety of correct, normal-sounding ways.

Mi helpis lin.

It is equally correct to say Mi helpis al li.

Li ŝatas katojn.

It is equally correct to say: Katoj plaĉas al li.

Ŝati used to mean "esteem" or "value", which demands an accusative in other languages. Plaĉi, the classical way to say "I like..." follows the Slavic and Romance model (piacere/gustar/нравиться). I suspect the re-purposing of ŝati to mean "like" is due largely to English influence.

Mi nomas vin amiko.

Well, this one just has to be learnt, but it's a simple rule: The predicative goes in the nominative case. In some languages, like Russian, it's the instrumental case.

The accusatives of direction and time are no more confusing than the multiple roles of de - which has at least three uses: possession, physical direction "from", and agent of a passive participle.

In Esperanto, the "opaque layer" of cases is mitigated by the fact you can often continue to use the same prepositions/cases/constructions as in your native tongue and still not sound strange.

nornen:

Li(1) ŝatas katojn(2).
Eo: (1) nominative; (2) accusative
De: (1) nominative; (2) accusative (Er mag Katzen.)
Es: (1) dative = CI; (2) nominative (Le gustan los gatos.)
Ru: (1) dative; (2) nominative (Eму нравятся коты.?????)

I personally looked up "ŝati" many, many times when I started with Esperanto, because I simply couldn't remember if it followed the model of German "mögen" or Spanish "gustar".

And then we have the accusative of measure, the accusative of time and the accusative of direction. Even adverbial accusatives.

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[1] Tempodivalse: Please correct my Russian examples. My Russian is more than rusty.

Thy Russian (and Spanish, by the way) examples are indeed correct.....in regards to case. However, there is a difference: In Esperanto and German, the verb means "to like". In Spanish and Russian it's "to be pleasing (to someone)" and naturally demands a dative to denote who is being pleased. For sxati and to like, the verb is the action of the one who is liking. In the Russian and Spanish examples, the verb is the "action" of the one that is liked.

orthohawk:Plus, it's always, ALWAYS rank beginners that do this! They come swooping in after a few days' of acquaintance with the language and say what amounts to, "Hey, even though I've known (or even known ABOUT) this language only a few days, I think you people that have been speaking it for years (or in some cases decades) are doing it all wrong! Here's the way it SHOULD work, ..........."

This is indeed always the case. I don't blame the beginners, people hear that Esperanto evolves and somehow this puts the idea into their heads that it is up for reforms that they suggest. I try to be nice about it, most beginners grow out of it as they actually learn the language. I had a dalliance with "na" as a beginner, obviously that is long gone now.

It does make it humorous when people suggest the thread should have been put in the Esperanto forums, however. 99% of people who make postings like this aren't capable of expressing their thoughts in Esperanto well enough to put such a post into the Esperanto forum and discuss it intelligently in Esperanto. And our forum's members are too helpful to simply refuse to answer the question and to say "learn the language well enough to post this in Esperanto and then we'll discuss it".

Tempodivalse:Ŝati used to mean "esteem" or "value", which demands an accusative in other languages. Plaĉi, the classical way to say "I like..." follows the Slavic and Romance model (piacere/gustar/нравиться). I suspect the re-purposing of ŝati to mean "like" is due largely to English influence.

English has never had a significant influence on Esperanto till the modern era, in my opinion. I actually think that ŝati underwent a very minor shift in meaning, and if you read old texts with the modern meaning of ŝati, they still make complete sense (unlike the "flugiloj de facila vento", which needs to be explained today). "Esteem" is the translation for it when the Academy officialized it, but you can find a person who "estimas kaj ŝatas" another person in an early work of Zamenhof, which indicates that it's clearly not the same as "esteem" in any case.

erinja:

Tempodivalse:Ŝati used to mean "esteem" or "value", which demands an accusative in other languages. Plaĉi, the classical way to say "I like..." follows the Slavic and Romance model (piacere/gustar/нравиться). I suspect the re-purposing of ŝati to mean "like" is due largely to English influence.

English has never had a significant influence on Esperanto till the modern era, in my opinion. I actually think that ŝati underwent a very minor shift in meaning, and if you read old texts with the modern meaning of ŝati, they still make complete sense (unlike the "flugiloj de facila vento", which needs to be explained today). "Esteem" is the translation for it when the Academy officialized it, but you can find a person who "estimas kaj ŝatas" another person in an early work of Zamenhof, which indicates that it's clearly not the same as "esteem" in any case.

Thanks for that clarification - I wasn't sure exactly how much the meaning had changed. Still, in old texts I tend to see plaĉi used more frequently, whereas today plaĉi seems noticeably less common than ŝati, at least in less formal contexts.

When I speak EO, I notice I'm usually the only one of my interlocutors to routinely use plaĉi. (I was also looked at funny when I said vagonaro instead of trajno.) I guess it's because I learned Esperanto from ancient books, and still read a lot of old texts (e.g. Fundamenta Krestomatio kind of stuff).

Thanks for all your comments and arguments. I'd like to summarize the main arguments (feel free to add or correct):

Negative points

• the accusative is very hard for beginners
  
• usefulness should outweigh tradition
  
• also other languages are changed (e.g. French)

Positive points

• Esperanto is a living language, it cannot be changed
  
• the word order is flexible, which makes it easier to use for different nationalities and for poems, literature, ...
  
• learning the accusative in Esperanto makes it easier to learn it in another language (e.g. Russian)

And because many complained about using English for such a topic, I will try my best to translate the list above into Esperanto:

Malavantaĝoj

• la akuzativo estas malfacilega por komencantoj
  
• utileco estas pli grava ol tradicio
  
• ankaŭ aliaj lingvoj (ekz. la franca) ŝanĝiĝas

Avantaĝoj

• Esperanto estas vivanta lingvo, oni ne povas ŝanĝi ĝin.
  
• la vortordo estas fleksebla, kion faciligas uzi Esperanton por diversaj nacioj kaj por poemoj
  
• lerni la akuzativon faciligas lerni aliajn lingvojn (ekz. la rusan)

I know that I'm a beginner and I feel sorry that my suggested "improvements" angered you.