What's simpler, noun declinations or prepositions?

I think that the most difficult part of learning Spanish, and other romance languages is the dizzying array of prepositions, and prepositional phrases. It seems to be the least structured part of the language(s)- that is to say, that theres no set of rules or logic to follow that governs their use, and you have to tediously go through and learn each instance seperately.

Sometimes I think that the grammatical simplification that romance languages have gone through has made them more irregular, and their use of prepositions is more difficult to learn than the latin noun declinations that they have replaced.

The latin inflectional grammar, however elaborate it may be, seems to be more consistent and logical. Wouldn't it be easier to just decline a noun in the dative or acusative case, than it would be to use the spanish preposition 'a' correctly?

any thoughts?

In my view Spanish prepositions are more predictable than in other romance languages such as French or Italian. Some examples:
(Spanish)
Voy al cine
Voy al teatro
Voy al doctor
(French)
Je vais au cinéma
Je vais au théatre
Je vais chez le médecin
(Italian)
vado al cinema
vado a teatro
vado dal dottore
(English)
I go to the doctor's
I go to the cinema
I go to the theatre
The only exception might be the prepotion A

If there were only one pattern of declensions and no irregularities, they would be good, but as it is they are more difficult.

Well, with declensions you still have to learn which case each verb takes. It's often predictable, but not always, and no more so than prepositions are predictable.

Russian:

Pomogat' KOMU-libo - to help someone (dative)
Ubivat' KOGO-libo - to help someone (accusative)
Zavidovat' KOMU-libo - to be envious of someone (dative)
Zhdat' CHEGO-libo - to wait for something (genetive)
Delat' CHTO-libo - to do something (accusative)
Pol'zovat'sya CHEM-libo - to use something (instrumental)

Not always predictable, you see. To a degree, but no more than prepositions.

The same with verbs which require prepositions:

prinuzhdat' k prestupleniyu - force someone to (towards) crime
tolkat' na prestuplenie - to incite someone to (on) crime

Don't languages with cases and declensions also have prepositions?

"Don't languages with cases and declensions also have prepositions"?

Good question! Generally languages with cases do have prepositions but fewer than languages without cases and their use is on the whole simpler. For instance Slavic languages, which are highly inflected, have no article and fewer prepositions than romance or Germanic languages. Some languages without cases have different types of articles, simple and contracted prepositions, for example Portuguese and Italian. On the other hand, German is a very peculiar language, it preserves a simplified system of cases but it also has lots of articles, prepositions and some contracted prepositions too. As far as agglutinative languages are concerned, such as Finnish, Hungarian, Estonian, Turkish.. They are generally supposed to possess plenty of cases but as a matter of fact those cases are only postpositions which are attached to nouns.

As for Turkish, you have to consider vowel harmony and consonant assimilation, if you attach a case suffix, so I don't think it's correct to say that cases are just postpositions attached to nouns in that kind of languages.

As an English speaker I'd say prepositions... Most languages that I've come in contact with use a combination of the two, but I have a much easier time grasping prepositions (for one reason or another, I'm not really sure why). In fact, I try to think of declensions as post-positions, and for some reason that helps me.

Would any non-native learner say that Latin's declension system is easier than English's use of word order and prepositions. I doubt it.

English is a very tough language, particularly at a high level. Syntax is a nightmare.

What I don't unnderstand is why people consider declensions to be hard? Maybe from a memory point of view or speaking smoothly, but from a grammatical point of view they are SIMPLE!

<<Syntax is a nightmare. >>

Don't all languages have synatx? Wouldn't a simple language (like English) with only syntax, and almost no inflection, be much simpler than a language with ghastly inflectional complexity along with the usual syntax problems?

Lithuanian still has prepositions, you just have to learn which case / inflection goes with each one!

Nom: Lietuva (Lithuania)
Acc: į Lietuvą (To Lithuania)
Dat: iš Lietuvos (From Lithuania)
Gen: Lietuvos (Of Lithuania)

I guess there are fewer prepositions than if there were no declensions though. German seems to be like this as well.

<<What I don't unnderstand is why people consider declensions to be hard?>>

Declensions are not hard, it's just that oftentimes along with declensions also come genders, usually three and a plural, and *this* is what makes declensions hard. 3 + 1 * #of declensions

Otherwise, declensions are probably easier than using prepositions