Whether we love and need them because it is one of the first facial expressions babies make, the fact that it indicates that someone is pleased to see us, or we have one when we are happy is all open to argument, but nobody can deny a smile isn’t something positive in our lives.
Every painting, photograph, or video we see where one or people are smiling is going to give us far more pleasure and good feelings than any that show frowns and scowls.