From the Internet Encyclopedia of Philosophy: "Normative ethics involves arriving at moral standards that regulate right and wrong conduct. In a sense, it is a search for an ideal litmus test of proper behavior. The Golden Rule is a classic example of a normative principle: We should do to others what we would want others to do to us... The key assumption in normative ethics is that there is only one ultimate criterion of moral conduct, whether it is a single rule or a set of principles. Unfortunately, philosophers do not agree about what precisely that criterion is..."
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