Date: 1701, 1704

"The application of our Thoughts to other Subjects is like looking upon the Rays of the Sun as it shines to us from a Wall, or upon the Image of it as it returns from a Watry Mirrour, but this is looking up directly against the Fons veri lucidus, the bright Source of Intellectual Light a...

— Norris, John (1657-1712)

Date: 1737, 1743

"The best way to prove the clearness of our mind, is by shewing its Faults; as when a Stream discovers the Dirt at the bottom, it convinceth us of the transparency and purity of the Water."

— Pope, Alexander (1688-1744)

Date: 1751, 1777

"They [cruel ideas] still haunt his solitary hours, damp his most aspiring thoughts, and show him, even to himself, in the most contemptible and most odious colours imaginable."

— Hume, David (1711-1776)