from Henry David Thoreau (12 July 1817 – 6 May 1862), an American writer and philosopher:
"Talk of mysteries! — Think of our life in nature, — daily to be shown matter, to come in contact with it, — rocks, trees, wind on our cheeks!
The solid earth! the actual world! the common sense! Contact! Contact!
Who are we? where are we?"
The Maine Woods Ktaadn, Pt. 6 (1848)