Even the most enlightened modern men and women continue to need moral standards. Generally accepted rules of conduct are just as essential as language to the kind of creature we are. They may lack the universality of natural laws like the law of gravity but they are just as much a part of the universe we inhabit as human beings. We cannot do without them. We still need ethical standards because they provide an essential lubricant that reconciles the selfish interests of the individual with the interests of the group.
Moral behavior allows people to get along with each other.
It is an essential ingredient of common sense. It is a common fallacy among those who still cling to the old-fashioned faiths that giving up that faith necessarily involves a descent into amorality, a social jungle where dog eats dog and the devil take the hindmost. Quite the contrary. In our time, as a new humanist spirit slowly infiltrates and supplants old-fashioned theism, modern ethical structures are gradually altering the moral precepts that were codified by the old religions and sanctioned by the common sense of bygone generations. Admittedly it is not easy to replace or modify old ethical principles, ones that have served many previous generations well, with new and untested formulas.