It’s basically a «X is Y» sentence, those often have «это» where Enlish has «is».
Well, maybe. I wouldn’t express the thought in this exact way (I’d go for something like «Есть и другая музыка, не только опера и балет»), but the suggested wording doesn’t sound incorrect.
"Not...and" feels like it stretches the bounds of natural English negation. It seems like the natural phrasing would use "or". I'm guessing I could go dig up a rule about logical conjunctions and disjunctions that would express this qualm in formal symbolic logic.
So I'm wondering if somebody can help me understand if negation of "ands" and "ors" in Russian obeys a fundamentally different schema (in keeping with the very different approach to "double" negatives, say)
I think you are correct except when the two items are closely related to one another.
Consider: "Not all the food here is cheese and crackers". This sounds much more natural than "Not all the food here is cheese or crackers". (I hope you agree and see where I'm coming from.)
I think this is the idea that Duolingo is getting at here: that opera-and-ballet is almost a single idea, rather than being two different examples of what the music isn't.
I think that's not because cheese and crackers are closely related, but because they are a "thing", a combination often served. You wouldn't say "Not all food is cheese and yogurt", although it isn't drastically wrong. You'd use "or". Consider set logic: the set of opera music and ballet music is that music which is used in both (intersection), but what you want to express is that not all music is in the union, or "or". (I'm half-serious here, though being analytical about this seems amusing.)
There's also a category error here: Not all music is opera or ballet music. ;)
Oftentimes, languages do not use the regular "operators" of formal logic; consider, for instance. People like to think that double negatives should be positive, but this is only true if the negative operator in a language is the logical-not, it might as well be the operator where you get the following truth-table, where ¤ is a stand-in for the relevant operator:
¤true = false ¤false = false
Such an operator exists in formal logic too, and no one calls that operator "illogical". My point here, basically is: trying to go for any direct analogy between logic or set theory may run foul of the fact that languages are evolved for economy of expression more often than precision of expression.
I do agree there's some kind of a problem with the translation into English here, though.
The naive application of logic to language (e.g. assuming the usual "logical negation" is the only possible "logical" negation) is one of my old pet peeves.
Although I basically agree and extend that to science and engineering ("organic" chicken does not mean it contains carbon atoms), what I was going for was illustration, not proof. In some cases the set theory usage aligns with everyday language - that's where it came from.
In English at least, the music for a ballet is also called a ballet.
See how the Wikipedia article for Swan Lake begins for example:
Swan Lake (Russian: Лебединое озеро/Lebedinoye ozero), Op. 20, is a ballet composed by Pyotr Ilyich Tchaikovsky in 1875–76.
I'm not sure how often the entire genre of music for ballet is called simply "ballet," but it doesn't sound weird to me, and there are some examples online, for example.
As a person who at certain times has listened to lots of classical music, and therefore had a need or desire to make further distinctions within that broad category, I could totally imagine myself talking about listening to "ballet," but I'm far from an expert. I'm just a guy who's got a lot of classical music.
Hi, I am not an expert on Russian, but I already know two Slavic languages, so let's give it a try)) Here the meaning is that there is something more than opera and ballet (both things are present). But in a case where there is none of those two things, I'd rather use 'или'('or'): У меня в городе нет оперы или кино (There is no opera or cinema in my town) У меня нет брата или сестры (I have no brother nor sister)
Looking at this with new eyes, the English idiom "not everything is wine and roses" now comes to mind. Obviously this sentence is tautological when read completely literally [there can be no one thing that is both wine and roses, their being different things and all], but that would be to miss the point. I suppose it's perfectly reasonable to conclude that the Russian version contains the precise same logical ambiguity but clear idiomatic meaning as the English one: "there are kinds of music that are neither opera nor ballet"
But on the other hand people in Russia often say "Мы вашего белорусского и украинского языка не понимаем!" (We don't understand your Belaruassian and Ukrainian"), so it seems that this is not a rule, but only a little suggestion. From my experience, I can say that the intuition will come with time, so don't give up)))
The genitive use you refer to is about non-existence more than simple negation. "Not all" is in fact a statement of existence (of additional kinds of music), not non-existence. Genitive would have been used were the sentence something like, "There is no music that is not opera or ballet."