Optimism is the madness of insisting that all is well when we are miserable.

Madness is to think of too many things in succession too fast, or of one thing too exclusively

Optimism," said Cacambo, "What is that?" "Alas!" replied Candide, "It is the obstinacy of maintaining that everything is best when it is worst.

What is madness? To have erroneous perceptions and to reason correctly from them

What a pessimist you are!" exclaimed Candide.
"That is because I know what life is," said Martin.

One day everything will be well, that is our hope. Everything's fine today, that is our illusion