I must say I am intrigued at the Tao suggestion that there is "no one there to know what cannot be known" . A sort of metaphysical "Catch 22", an endless loop of inscrutability. I understand that a more modern philosopher, Heidegger, suggested that "if there is nothing there" is that "nothing" still "something" in the sense that there must be a reason for the "nothing". What made it? Why is there "nothing" there? See Madam Flora's drunken soliloquy in Menotti's "The Medium" ("But if there is nothing there, why am I so afraid of that nothingness?")
If this posting is "off thread" you may remove it and put it out of its misery. Perhaps you should do the same for whoever who posted it.
W.