《论衡·卷四·书虚篇》
考察鲁国离吴国，有一千多里，假使让离朱来看，最终还是不能看见，何况是叫颜渊，他怎么能看清楚呢？
案鲁去吴，千有余里，使离硃望之，终不能见，况使颜渊，何能审之？
The survey shows that there are more than a thousand miles from the state of Lu to the state of Wu. Even if we let Lijun see, he still cannot see it, so how can we expect Yan Yuan to see it?