Be kind, for everyone you meet is fighting a hard battle.
Plato (possibly – it is disputed)
[I]in the whole world there are really only two problems. [..] One problem is, “you know what you want but you don’t know how to get it”, and the only other problem is, “you don’t know what you want.”
Not to be absolutely certain is, I think, one of the essential things in rationality. […] When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others.
Bertrand Russell, “Am I An Atheist Or An Agnostic?”
I’m not sentimental – I’m as romantic as you are. The idea, you know, is that the sentimental person thinks things will last – the romantic person has a desperate confidence that they won’t.
F. Scott Fitzgerald, “This Side of Paradise”