Double negation of an i-adjective


Does it exist as such, the double negation of an i-adjective, e.g.: おいしくなくない?
I was told that I should use おいしくなく は ない instead. Is that right? Is it a rule?
Would it depend on context which was a question like: Are the meals at that
restaurant good? Or is it just the style of the person I talked to?

Of course, I could also use e.g. まずくない instead, but this is not the question
here.




The double negation of i-adjectives not only exists, but it is quite commonly
used among us native speakers when expressing opinions **indirectly**.

Take 「おいしい」 ("tasty") for example, by far the most common double-negative form
would be:

> 「おいしくなく **は** ない」

which means:

> "(the food) is okay/passable if not great"

That sounds fairly indirect, doesn't it? The direct phrase would simply be
「まずい」 ("bad-tasting") or 「おいしくない」, which would often be considered too direct
for the Japanese taste (pun intended).

We also say:

> 「おいしくなく **も** ない」

which means practically the same thing as 「おいしくなく **は** ない」.

I do not think that careful speakers would use 「おいしくなくない」 with no particle
between the 「なく」 and 「ない」 to mean the same as the two above. I would, however,
not be surprised if I heard it in careless hurried speech.




The double negation of i-adjectives not only exists, but it is quite commonly
used among us native speakers when expressing opinions **indirectly**.

Take 「おいしい」 ("tasty") for example, by far the most common double-negative form
would be:

> 「おいしくなく **は** ない」

which means:

> "(the food) is okay/passable if not great"

That sounds fairly indirect, doesn't it? The direct phrase would simply be
「まずい」 ("bad-tasting") or 「おいしくない」, which would often be considered too direct
for the Japanese taste (pun intended).

We also say:

> 「おいしくなく **も** ない」

which means practically the same thing as 「おいしくなく **は** ない」.

I do not think that careful speakers would use 「おいしくなくない」 with no particle
between the 「なく」 and 「ない」 to mean the same as the two above. I would, however,
not be surprised if I heard it in careless hurried speech.

