Part of the resonance and power of that famous refrain, "a terrible beauty is born," is that this beauty is being born not only in the world but in Yeats's poetry.

部分激发联想的力量,以及那著名的叠唱的力量，一中惊人之美诞生了“,那种美,不仅诞生于现实世界,也诞生于叶芝的诗歌。

耶鲁公开课 - 现代诗歌课程节选

The swan is really only a force, and Yeats's concern is rather with the human experience of that force, which is, again, another manifestation of "terrible beauty."

这天鹅只是一种力量，而叶芝所关注的是,人类对此力量的感受，而这又是，一次，惊人之美，的表现“

耶鲁公开课 - 现代诗歌课程节选