the world a letter

Trying to sort out Lao Tzu can be tricky, even in Chinese I understand. So I look at different translations (this place helps, though it is kind of overwhelming) and have an edition which gives a word-by word (ideogram-by-ideogram) breakdown of possible translations. And of course my meditation invests my sense of meaning strongly.

So here's how I suss out verse 71:

Knowing unknowing is health, while
not knowing unknowing is sickness.

Sicken your sickness, and you will grow well;
Wisdom is to live healthy, cultivating no sickness, and therefore enduring none.

Here's that website's 29. I took the above path through this passage because it follows what I understand of the Daoist view of health: that sickness only arrives when one is depleted of good qi, and the maintenance of good qi is most surely dependent on that basic good meditation of mindlessness which allows good qi to flow. That an unhealthy mind inevitably eventually results in unhealthy qi flow lets all the levels of metaphysical understanding the various translations I linked to above work fine. And is the sense, I think, behind what is, in my try, the fourth line of the verse.