As an atheist, I believe that the concepts of "right" and "wrong" are just illusions used by people in power to manipulate others and keep the general population docile.  People do not like to face the fact that their life is their own, they do not like to take responsibility for defining it, so they accept the oversimplified dichotomy of "good" and "evil" as imposed from outside authorities.  I find myself perfectly capable of operating independent of and such primitive concepts, I am no slave.