in Thoreau’s Journal:

As I walk the RR causeway, I am, as the last two months, disturbed by the sound of my steps on the frozen ground. I wish to hear the silence of the night, for the silence is something positive to be heard. I cannot walk with my ears covered. I must stand still and listen with open ears…

Silence alone is worthy to be heard. Silence is of various depth & fertility like soil….

A night in which the silence was audible—I hear the unspeakable.