The short of it:
Knowing is not knowing.
71. The Disease of Knowing.
The best part of knowledge is (conscious) ignorance. The disease of ignorance is (the conceit of) knowledge. If one only takes this disease for what it is, a disease, [they] will thereby be free from it. The sage has not this disease, because [they take] it for what it is, and straightway [they are] free from it.
71. ‘The Disease of Knowing.’
71.1 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.
71.2 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. [They know] the pain that would be inseparable from it, and therefore [they do] not have it.
71. (Untitled).
To know that you do not know is the best. To pretend to know when you do not know is a disease. Only when one recognizes this disease as a disease can one be free from the disease. The sage is free from the disease. Because [they recognize] this disease to be disease, [they are] free from it.
the long of it:
Not-knowing is another variation on Lao Tsu’s non-action (see Chap 43). Every action involves a non-action. And every thing we know involves something we don’t know (see Chap 48). As long as we recognize this, we will be okay. The danger starts when we think we know everything, which we never can.
-TB