What is the purpose of なの in これらの話は本当のことなのか?


I heard

> これらの話は本当のことなのか

from this [video clip about Gozo Shioda
sensei](https://youtu.be/LD1enmK_5Ak?t=174).

What is the purpose of なの in これらの話は本当のことなのか?

It seems to be redundant because

> これらの話は本当なのか or これらの話は本当ですか

might be sufficient.




> It seems to be redundant because これらの話は本当 _な_ のか or これらの話は本当ですか might be
> sufficient.

Well, if you think the expression これらの話は本当のことなのか has elements that can be
dispensed with, _syntactically_ you are correct.

My guess is that the scenario incorporated the expression in view of
emphasising the subject of the film.




> It seems to be redundant because これらの話は本当 _な_ のか or これらの話は本当ですか might be
> sufficient.

Well, if you think the expression これらの話は本当のことなのか has elements that can be
dispensed with, _syntactically_ you are correct.

My guess is that the scenario incorporated the expression in view of
emphasising the subject of the film.

