To know and yet think we do not know is the highest attainment; not to know and yet think we do know is a disease.

It is simply by being pained at the thought of having this disease that we are preserved from it. The sage has not the disease. As shown in Chapter 56, those who know do not speak and those who speak do not know — true knowledge conceals itself. And as Chapter 70 shows, the sage wears coarse cloth while carrying jade within — outwardly unknowing, inwardly luminous. He knows the pain that would be inseparable from the disease of false knowing, and therefore he does not have it.