明míng察chá秋qiū毫háo

Literal: clear sight that makes out autumn down
Figurative: To be so sharp-eyed that not even the smallest detail slips past; usually praise for someone who judges, investigates or supervises.

Where does 明察秋毫 come from?

It comes from the 《孟子》. Mencius is trying to persuade King Xuan of Qi that he is capable of ruling with benevolence, and puts a case to him: if someone claimed his eyes could make out the tip of the fine down animals grow in autumn, yet could not see a cartload of firewood, would the king believe him? The king says no. Mencius concludes that what the king lacks is not ability but will: his kindness reaches animals but not his people. The idiom kept that "seeing autumn down clearly," and today praises someone who catches the smallest detail, especially when judging or investigating.

Source (出处): 《孟子·梁惠王上》

How is 明察秋毫 used? Two examples

我wǒ只zhǐ动dòng了le一yī下xià他tā桌zhuō子zi上shàng的de笔bǐ，他tā一yī进jìn门mén就jiù发fā现xiàn了le，真zhēn是shì明míng察chá秋qiū毫háo。
All I did was move a pen on his desk, and he noticed the moment he walked in; nothing gets past him.
审shěn计jì员yuán明míng察chá秋qiū毫háo，连lián一yī张zhāng发fā票piào上shàng的de小xiǎo错cuò误wù都dōu没méi放fàng过guò。
The auditor missed nothing; not even a tiny error on a single invoice got past him.

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