also: なにゆえに
why; how come
A slightly emphatic or literary way to ask 'why' or 'how come', more formal than なぜ. Often used in rhetorical questions or poetic contexts.
I can't understand why you did such a thing.
Why do people fight?
Kanji spelling is rare and literary; the reading なにゆえに is also possible for this form.
Rare and formal reading; the kanji form 何故に can also be read this way.
Derived from なぜ (why) with the particle に, adding emphasis or a literary tone. The reading なにゆえに is a more literal reading of the kanji 何故に.