Do you know the story of 'The Selfish Giant?'by Oscar Wilde? It's sometimes taught in the school.There you certainly see how bad selfishness is! Although self love or self respect is good for us, but selfishness is really very bad.A selfish man always thinks of himself.It is the main root of all evils.As a result, he or she loves himself or herself most,thinks only of own happiness and success.
They never loved by others,he is friendless and helpless also.Dishonesty, cruelty and meaness are bitter fruits of selfishness.It ultimately leads to unhappiness and ruin.Because true happiness comes from great sacrifice and selflessness.Thus we find that the Selfish Giant was so unhappy in the story book.Even he was punished also.
So be unselfish and think of others.Thus you will make others happy and happy yourself in life obviously.