A smile doesn't cost anything, but it's so precious. It makes someone who accepts it rich without making poor the person who gives it.
It lasts only a moment but its memory is many times forever.
A smile rests a tired person gives courage to a disappointed one comforts the sad one, boosts the hopefulness and creates happiness in the house. And though cannot be borrowed, cannot be stolen, cannot be bought cannot be taken by force, because it's something that has value when it's given. And if one day meets somebody who will not donate the smile you deserve to be generous and higher people and you give yours because nobody needs it more than the person who can give it, too.