だ versus な in causal subordinate clauses

Question

Why do causal subordinate clauses ending in -から take だ as a means to connect nouns and な adjectives (e.g. 日本人だから), whereas causal subordinate clauses ending in -ので take な (e.g. 日本人なので)?

I read that だ derives from て+ある, whereas な derives from に+ある, but why would one causal conjunction require で, whereas another one requires に?

Just trying to make sense of it all…

Thank you!

Possibly related https://japanese.stackexchange.com/questions/12097/etymology-of-the-copula-%E3%81%A0 — Leebo, Jul 23 '18 at 09:08

score 3 · Accepted Answer · answered Jul 23 '18 at 13:13

3

This explanation is tautological but I just have to say it's because から follows a terminal form, which of the copula is だ while の is a kind of noun, which needs an attributive form to be modified, which of the copula is な.

Their etymology has nothing to do with this issue.

answered Jul 23 '18 at 13:13

user4092

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I think the OP wants to know why there are two forms though... that's the question. – Leebo Jul 23 '18 at 14:15
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@Leebo That's because many verbs originally had two forms, which later got merged into one except the copula. – user4092 Jul 24 '18 at 03:30
That actually kinda clears it up… Thank you! – Pregunto Jul 24 '18 at 07:57

だ versus な in causal subordinate clauses

1 Answers1