《文心雕龙·声律》
一般散文容易写得精巧，但要把一篇散文的声律调配和谐就很难；诗歌写作虽不易精巧，押韵却是比较容易的。
属笔易巧，选和至难，缀文难精，而作韵甚易。
It is easy to write a concise and elegant essay, but it is much harder to balance the euphony of a prose piece; a verse is harder to make concise and elegant, but it is comparatively easier to make it rhyme.