" The English word “ethic” or “ethics” comes from the Greek word ethos. The word “morals” or “morality” comes from the word mores. The difference is that the ethos of a society or culture deals with its foundational philosophy, its concept of values, and its system of understanding how the world fits together. There is a philosophical value system that is the ethos of every culture in the world. On the other hand, mores has to do with the customs, habits, and normal forms of behavior that are found within a given culture. "

― R.C. Sproul , How Can I Develop A Christian Conscience? (Crucial Questions, #15)