You know when you’re, like, in that, like, frame of mind when things, just, like, aren’t, you know, aren’t mixing… No, not mixing. Joining. Converging. No, what’s that word? Means, um… coalescing. That’s not it either, but that’s good enough. Anyway, you know how in that kind of, like, situation, when things just aren’t going your, like, way, and things are just, like falling apart all around you and stuff?
Sucks, huh?
From that famous and deep thinker/cowboy Curly Washburn (played by Jack Palance) in the movie City Slickers. Its the secret to being happy in life. Something to the effect of:
“Its that one thing. Figure out that one thing and you’ll be happy”
But, that “one thing” may or may not be a specific thing. It may well be totally different for different people…its your personal thing and you need to figure it out.
“If you’re going through hell, keep on going.”
“Fall down seven times, get up eight.”
(I’m an author, so this is especially significant to me.) “Go to your studio and make stuff.” (Write stuff, in my case.)
Makes me think of this one:
“No single snowflake thinks it’s responsible for the avalanche.”
Anyway, here’s one that comes to mind often when I deal with defendants who blame everyone and everything but themselves for their situation:
“What have you done today to make your life better?”
And one from Sports Night that has stuck with me:
“If you’re stupid, surround yourself with smart people. And if you’re smart, surround yourself with smart people who disagree with you.”
“I disagree with what you say, but I will defend to the death your right to say it.” - attrib. to Voltaire
“Ask not what your country can do for you, but what you can do for your country.” - John F. Kennedy
“Most people are just about as happy as they decide to be.” - Abraham Lincoln
“The law is reason free from passion.” - Aristotle
“Golf is a good walk spoiled.” - attrib. to Mark Twain
“Where everyone thinks alike, none think very much.” - Chester Bowles
“Do a good turn every day.” - Robert, Lord Baden-Powell
Dunno who first said these, but they’ve stuck with me:
“Democracy means paying attention.”
“Nobody on his deathbed ever wished he’d worked more.”
“If you want a friend, be a friend.”
A kind of odd one that has held true so far:
“It could be worse; you could be on fire.”
“Slumbering in every human being lies an infinity of possibilities, which one must not arouse in vain. For it is terrible when the whole man resonates with echoes and echoes, none becoming a real voice.” -Elias Canetti, Notes from Hampstead
Oh, yeah. I love Twain quotes as well. You can look at the quote from Shaw and see it in various people. Perfect example is Steve Jobs. Now, I am no Apple fanboi, but I have to admit that Steve Jobs did things his way and did change the world with his vision (to the extent that portable electronic devices are going to do so). These people are relatively rare and I always feel I should work to become more unreasonable.
Some days I need to remember this one! 
“Life ain’t always what you think it should be.”
“In matters of style, swim with the current; in matters of principle, stand like a rock.”
The second is Thomas Jefferson. The first is from some country song. An unlikely source, perhaps, but damn if it’s not true.
“The summit of Mt Everest is marine limestone”.
“Heat is caused by vibrating molecules. The faster they vibrate, the hotter they are.”
For musicians, but also applicable to other activities:
Good players practice until they get it right. Great players practice until they can’t get it wrong.
I’ve never heard that before. I like it!
My father used to tell me, “Good musicians can still make mistakes, but they keep on going and cover skillfully.”
“All my possessions for a moment of time.”-Elizabeth I
“He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you.”- Fredrick Nietzsche
“A coward is afraid and does nothing. A brave man is afraid, but does it anyway.”
B. Serum and Stoid, I’ve always heard it as “Extraordinary claims require extraordinary evidence” and it is attributed to Carl Sagan in Cosmos.
My own contribution:
“In three words I can sum up everything I’ve learned about life — it goes on.” --Robert Frost
When you do things right, people won’t be sure you’ve done anything at all - my favourite line from Futurama, and also true.
There shall be but one mistress here, and no master - Elizabeth I. I like this because I don’t think it’s just about her reluctance to marry, I think it can be about being accountable to yourself.
Have patience with everything unresolved, and try to love the questions themselves - Rilke. To which Irvin D. Yalom adds: Try to love the questioners as well.
“There are two classes of human beings. One has ideas, which it believes in fully, perhaps, but modifies to bring about “success”. The other class has ideas which it believes in and must carry out absolutely; success or no success. The first class has a tremendous majority, and they are all slaves. The second class are the only free people in the world.”
“The true measure of a man is how he treats someone who can do him absolutely no good.” - Samuel Housing (maybe)
“It is better to know some of the questions than all of the answers.” ~~James Thurber
“Believe those who seek the truth; doubt those who find it.” ~~Andre Gide
“Life is what happens while you are making other plans.” ~~John Lennon
“Every normal man must be tempted at times to spit on his hands, raise the black flag and begin to slit throats.” ~~H.L Mencken
“The older the violin, the sweeter the music.” ~~Augustus McCrae