That would be "niente in comune" or "nulla in comune".
No, because, "to have in common" and "to be similar" are two different statements. "Similar" means that two or more objects are identical, or nearly so. "In common" means that two or more objects, not necessarily identical, have at least one attribute of an identical nature between them.
It's "in comm
on" and it means [for groups of people or things] to resemble one another in specific ways.
- Bill and Bob both have red hair. They have that in common with each other.
- Bob and Mary have a lot in common. I can see why they like each other.
To have something in common = to share interests or characteristics
- What these very old objects have in common is that they were all stolen and smuggled out of the country.
- What does the new model have in common with earlier versions?
Usage notes: also used in the forms have nothing in common and have a lot in common.
- The two women had absolutely nothing in common.
- The two men had a lot in common and got along well.
Source: The Free Dictionary
So "Io non ho niente di simile" could be translated to:
- I do not have anything similar
- I have nothing similar
- I have nothing which has something in common with it
"I don't have anything the same" is wrong for two reasons. Syntactically, "(the) same" is either a pronoun or an adjective, so it could be used either without the (pro)noun "anything" or before it (actually it should be simplified to just "thing", because "any" does not work well with "same"):
- I don't have the same
- I don't have the same anything (?!?)
- I don't have the same thing
Semantically, "the same" describes a very strong similarity, either two observations of a single object or two identical objects. Thus, "of the sort" or "similar" are much better for "simile".
Do double negatives exist in Italian? With one of the translations of "niente" being "nothing", this sentence could read "I don't have nothing similar" - bad English I'm aware, but this direct translation contains ambiguity due to the double negative. Presumably the Italian doesn't contain this ambiguity, can anyone explain why not? Can anyone provide examples of actual double negatives in Italian?
Double negation with negative meaning is used a lot in Italian. One notable case for not using double negation is when a negative pronoun such as nessuno/niente is used as a subject.
This is an excellent explanation by Gabriele Petronella:
In Italian double negation is generally used with negative meaning, like in the following examples:
- Non conosco nessuno
- Non guardo mai la televisione
- Non posso farci niente
The way you can think about this is to consider the first negation as not having effect on anything else apart from the verb.
With this "rule", non only serves the purpose of turning the verb into its negative form, but it doesn't affect the rest of the sentence.
This is also coherent with some other examples in which two negations on verbs make the sentence a positive one:
- Non credo di non essere capace
- Non dico che non sia appropriato
In both sentences the negation is attached to the verb, and two negated verbs turn the sentence into a positive one. It's worth noting, though, that although both
- Non credo di non essere capace
- Credo di essere capace
are expressing a positive sense, they are not interchangeable, the former expressing a higher degree of doubt about the subject's abilities.
Finally, as an addition, Italian is not the only language making an extensive use of double negations. Spanish is another notable example:
- No conozco nadie
- No puedo hacer nada