"Is a myth a kind of philosophy?"

Translation: Είναι ένας μύθος ένα είδος φιλοσοφίας;

[PhilSimmonds]

it also gives ενας μυθος which seems to be more correct.

[Dimitra956826]

Both are equally correct. ^.^ In this case, "o" instead of "ένας" doesn't make the context more specific than it should be, so no need to worry. ^.^