To know yet appear not to know is superior. Knowing how to speak of not knowing is the highest virtue. Not knowing but pretending to know is a sickness. {{To not know yet speak of knowing is the sickness of virtue. Only by regarding sickness as a sickness can one remain free from sickness. Because only those who recognize the illness of many people's overconfidence in knowledge do not fall into their own illness. The sage is free from sickness because he regards sickness as a problem; therefore, he remains free from sickness. The sage does not suffer from this illness of overconfidence in knowledge because he constantly laments that many people have this illness; thus, it is not his own problem, so he does not fall into the same sickness. The sage possesses comprehensive and penetrating knowledge but pretends not to know; this is done in order to encourage all under heaven to remain simple, sincere, and upright, each preserving their pure nature. The petty person does not understand the meaning of the Dao and recklessly engages in acts of overconfident knowledge to show off, thereby harming their spirit and vitality internally, shortening their life span. ---