Date: 1800

"The inner world, his microcosmus, is / The deep shaft, out of which they spring eternally."

— Schiller, Friedrich (1759-1805)

Date: 1818, 1859

"Now this is by no means possible, for as soon as we turn into ourselves to make the attempt, and seek for once to know ourselves fully by means of introspective reflection, we are lost in a bottomless void; we find ourselves like the hollow glass globe, from out of which a voice speaks whose cau...

— Schopenhauer, Arthur (1788-1860)