Whether humanity will consciously follow the law of love, I do not know. But that need not disturb me. The law will work just as the law of gravitation works whether we accept it or not.
To be kind, honest and have positive thoughts; to forgive those who harm us and treat everyone as a friend; to help those who are suffering and never to consider ourselves superior to anyone else: even if this advice seems rather simplistic, make the effort of seeing whether by following it you can find greater happiness.
If you train your mind to search for the positive things about other people, you will be surprised at how many good things you can observe in them and comment upon.