This chapter always makes me nervous: “Those who know, do not speak. Those who speak, do not know.” I’ve been writing about, teaching about, and speaking about the Tao for over three decades. Do I know anything anymore? If I had to choose between speaking and knowing – which do you think I’d choose? What am I to do?
William Martin 
My understanding is Lao Tzu chose not to leave in silence, but wrote down the expression of what he saw was the Tao Te Ching. However, this imprint left the warning that what was written did not reflect what actually was. Lao Tzu was an expression of nature. Bill is an expression of nature. Alex is an expression of nature. By stifling and restricting the expression that arises naturally within ourselves merely to avoid sharing with others we are not honouring that which cannot be truly understood (our Self). Once we have expressed ourselves, perhaps then is the moment we heed the suggestion to stay silent. To reflect on the expression offered. Learn from it if needed, or, let it trickle down the stream of life for what it was: a passing moment. By living in a cave alone and silent we would learn nothing of living as part of nature. Thank you for your expression.
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