A man without a smiling face must not open a shop. - Dale Carnegie

If we want to make friends, let’s put ourselves out to do things for other people – things that require time, energy, unselfishness and thoughtfulness.

"A good deed, "said the prophet Mohammed, "is one that brings a smile of joy to the face of another."
Why will doing a good deed every day produce such astounding efforts on the doer?
Because trying to please others will cause us to stop thinking of ourselves: the very
thing that produces worry and fear and melancholia.

Happiness doesn’t depend on outward conditions. It depends on inner conditions. It isn’t what you have or who you are or where you are or what you are doing that makes you happy or unhappy. It is what you think about it.