《新唐书·列传·卷一百一十二》
一五一十地陈述了那人的情形，杨玄萛赞叹说： 不是你辨明是非，从谁那儿弄清这件事？ 
具言其状。玄实叹曰： 非尔明辨，孰由知之？ 
He gave a detailed account of the man's situation, and Yang Xuanxu exclaimed: “If it weren't for you clarifying the right and wrong of this matter, then who could have made sense of this?”
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 具言其状。玄实叹曰： 非尔明辨，孰由知之？  [/INST] He gave a detailed account of the man's situation, and Yang Xuanxu exclaimed: “If it weren't for you clarifying the right and wrong of this matter, then who could have made sense of this?”</s>
Identify the key themes in this Classical Chinese text and explain them in English: 具言其状。玄实叹曰： 非尔明辨，孰由知之？
user
He gave a detailed account of the man's situation, and Yang Xuanxu exclaimed: “If it weren't for you clarifying the right and wrong of this matter, then who could have made sense of this?”
assistant