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)

Date: 1805-6, published 1833-6

"Knowledge itself is in fact the unity and truth of both moments; but with Kant the thinking understanding and sensuousness are both something particular, and they are only united in an external, superficial way, just as a piece of wood and a leg might be bound together by a cord."

— Hegel, G. W. F. (1770-1831)

Date: 1851

"Just as a spring, through the continual pressure of a foreign body, at last loses its elasticity, so does the mind if it has another person’s thoughts continually forced upon it."

— Schopenhauer, Arthur (1788-1860)

Date: 1867

"As capitalist, he is only capital personified. His soul is the soul of capital."

— Marx, Karl (1818-1883)