The Timing of Sages

"Hence the sages did not treat those who were already ill; they instructed those who were not yet ill. They did not want to rule those who were already rebellious; they guided those who were not rebellious. To administer medicines to diseases which have already developed and to suppress revolts which have already developed is comparable to the behavior of those persons who begin to dig a well after they have become thirsty. Would these actions be not too late?"

-Huang Di Nei Jing Yellow Emperor's Cannon of Internal Medicine