The Golden Rule, or Ethic of Reciprocity, states that you should treat others as you would like others to treat you. It is present in nearly all spiritual paths that are based on universal love, as well as some secular philosophies.
So… why don’t we practice it?
“Every religion emphasizes human improvement, love, respect for others, sharing other people’s suffering. On these lines every religion had more or less the same viewpoint and the same goal.”
~ His Holiness the Dalai Lama