《荀子·大略》
现在那丢了针的人，整天找它都没找到；当他找到它时，并不是眼睛更加明亮了，而是睁大了眼睛才发现它的。心里考虑问题也是这样。
今夫亡箴者，终日求之而不得；其得之也，非目益明也，眸而见之也。心之于虑亦然。
Now the man who lost the needle has been looking for it all day but has not found it. When he finds it, it is not because his eyes are brighter, but because he opens his eyes wide to find it. That's how it is with thinking.