Providing definitions/explanations with というのは　～のこと/ということだ


Recently I've been trying to wrap my head around the Tobira textbook grammar
point on というのは and from my understanding [Aというのは Bのことだ/ということだ] essentially
means [A means B]. However, I can't seem to understand the nuances of the
sentence ending のこと/ということ.

> ｢関東地方」というのは東京のことですか。  
>  Does Kanto Region mean Tokyo?

Why is 「のことですか。」 used here? Would ｢関東地方」というのは東京ですか。 and ｢関東地方」というのは東京ということですか。
also be appropriate? Do all three mean the same thing? When would one form be
more appropriate over the other?




AはBのことだ is "A means B". Aというの is "what's called A".

So, ｢関東地方」というのは東京のことですか is "Does what's called Kanto Region mean Tokyo?".
(Incidentally, the answer is no)

｢関東地方」というのは東京ということですか can mean the same thing as …東京のこと… but that という(こと) is
more likely to denote a clause. It sounds like 東京(にいる)ということ or "By saying
'Kanto Region', do you mean you've been to Tokyo?".




AはBのことだ is "A means B". Aというの is "what's called A".

So, ｢関東地方」というのは東京のことですか is "Does what's called Kanto Region mean Tokyo?".
(Incidentally, the answer is no)

｢関東地方」というのは東京ということですか can mean the same thing as …東京のこと… but that という(こと) is
more likely to denote a clause. It sounds like 東京(にいる)ということ or "By saying
'Kanto Region', do you mean you've been to Tokyo?".

