What are some optimistic quotes you know?

Develop the mind of equilibrium. You will be always getting praise and blame but donot let either effect your poise of mind, follow the calmness, the absence of pride.

In life, there are just two things to worry about.
Either you are well or you are ill.
If you are well, you have nothing to worry about !
If you are ill, there are just two things to worry about.
Either you'll get better, or you'll die !
If you get better, there is nothing to worry about !
If you die, there are just two things to worry about.
Either you'll go to Heaven or you'll go to Hell.
If you go to Heaven, then you've nothing to worry about !
And if you go to Hell. Well, chances are you'll be so busy shaking hands with all your old friends, you won't have time to worry !

"I tell you, we are here on Earth to fart around, and don't let anybody tell you different." Kurt Vonnegut

"I urge you to please notice when you are happy, and exclaim or murmur or think at some point, “If this isn’t nice, I don’t know what is." Kurt Vonnegut

Not really optimistic, but something to consider after taking life too seriously.