Optional Foreword: I understand pronouns such as 'none, no one, nobody', if they're the subject of one independent clause. But the quote below (encountered herein) confuses me.
I ask here (and not on the English SE sites), because my ordeal with this problem also in French and Spanish, betrays a deeper linguistic problem, independent of a specific language.
(TL;DR) [Original Source]
'category' should be used by no-one who is not prepared to state [the following] [...].
I can't pinpoint the source of my confusion; so please advise. However, I suspect that I'm troubled by the use of who (the relative pronoun) to refer to no-one (its antecedent).
How can a pronoun refer to a nonexistent someone or something? Is this nonsensical?
In the sentence above, if 'category' should be used by no-one, then no one exists.
So how can you continue to consider this no-one, especially with a relative clause?
I already deduced, and so ask NOT about, the meaning of the above:
One should use 'category' only if prepared to state [the following].