And the sages did not treat those already sick, they treated them before they were sick. In government they did not deal with the catastrophe after it had arrived, they dealt with it before it had happened. This is a commonly known fault.
Therefore when sickness has begun to take hold and you medicate, or when catastrophe has taken hold and you attempt to govern, it is like being thirsty and looking to dig a well, or casting weapons on the way into battle. This is just too late.
— Huang Di Nei Jing Su Wen, The Yellow Emperor’s Classic of Medicine