Be yourself; everyone else is already taken.
Whatever the mind of man can conceive and believe, it can achieve.
My dear friend, clear your mind of cant.
Never let the future disturb you. You will meet it, if you have to, with the same weapons of reason which today arm you against the present.
United we stand; divided we fall.
The secret of health for both mind and body is not to mourn for the past, nor to worry about the future, but to live the present moment wisely and earnestly.
Courage is the thing. All goes if courage goes.
Become a possibilitarian. No matter how dark things seem to be or actually are, raise your sights and see possibilities -- always see them, for they're always there.
Isn't it astonishing that all these secrets have been preserved for so many years just so we could discover them!
When it comes down to it, I let them think what they want. If they care enough to bother with what I do, then I'm already better than them.
Be the change that you wish to see in the world.
I'm sorry I wrote you such a long letter; I didn't have time to write a short one.
We are all in the gutter, but some of us are looking at the stars.
It's not whether you got knocked down; it's whether you get back up.
Others have seen what is and asked why. I have seen what could be and asked why not.
Your pain is the breaking of the shell that encloses your understanding.
The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
All thinking men are atheists.
You must find the place inside yourself where nothing is impossible.
People who are unable to motivate themselves must be content with mediocrity, no matter how impressive their other talents.
Anyone who stops learning is old, whether at twenty or eighty. Anyone who keeps learning stays young.