"The mountain, the water's surface, and the ring of forest formed a diametrical middle plane separating two identical, equally spacious and complementary concavities--one above, the other below. I floated, my canoe making a soft indentation in the sky, a portable personal portal connecting me to both hemispheres simultaneously. It was the clearest picture of the universe as we experience it I had ever known. Thoreau's observation, previously obscure to me, that the 'universe is insular, not continent,' sprang into focus. We live inside a sphere as much as on the surface of one."
- Christopher Shaw, Sacred Monkey River: A Canoe Trip With the Gods