We are strangely made. We think we are wonderful creatures. Part of the time we think that, at any rate. And during that interval we consider with pride our mental equipment, with its penetration, its power of analysis, its ability to reason out clear conclusions from confused facts, and all the lordly rest of it; and then comes a rational interval and disenchants us. Disenchants us and lays us bare to ourselves, and we see that intellectually we are really no great things; that we seldom really know the thing we think we know; that our best built certainties are but sand-houses and subject to damage from any wind of doubt that blows.
- "The Great Dark"

AI image created by R. Kent Rasmussen

...when all is said and done, the one sole condition that makes spiritual happiness and preserves it is the absence of doubt.
- Autobiography of Mark Twain, Vol. 3 (2015)