The spirit desires to remain with its body, because, without the organic instruments of that body, it can neither act, nor feel anything.Leonardo da Vinci
The painter who draws merely by practice and by eye, without any reason, is like a mirror which copies every thing placed in front of it without being conscious of their existence.Leonardo da Vinci
Strange to say, the luminous world is the invisible world; the luminous world is that which we do not see. Our eyes of flesh see only night.Victor Hugo
How can you prove whether at this moment we are sleeping, and all our thoughts are a dream; or whether we are awake, and talking to one another in the waking state?Plato
When brains get sufficiently big, presumably, as human brains have, consciousness seems to emerge.Richard Dawkins