《资治通鉴·后汉纪·后汉纪三》
所以说，善于为国家着想的，不敢在小事上马虎，而且经常杜微防渐，能不警惕吗？
是以善为天下虑者，不敢忽于微而常杜其渐也，可不戒哉！
Therefore he said, "A person who is good at thinking of the country does not dare to be careless in small matters, and often stops the micro and prevents the gradual, can he not be vigilant?"