The term “natural law” is open to more than one interpretation. It refers to a type of moral theory, as well as to a type of legal theory, but the base claims of the two kinds of theory are logically independent. According to natural law moral theory, the moral standards that control human behaviour are, in some sense, objectively lacks from the nature of human beings and the nature of the world. While being logically independent of natural law legal theory, the two theories inter link with one another.
Normative ethics involves arriving at moral standards that regulate what is right and wrong. In a sense, it is a search for an ideal test of proper behaviour. 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. Since I do not want my neighbour to steal my car, then it is wrong for me to steal her car. I can theoretically determine whether any possible action is right or wrong. So, based on the Golden Rule, it would also be wrong for me to lie to, harass, victimize, assault, or kill others. The Golden Rule is an example of a normative theory that establishes a single principle against which we judge all actions. Other normative theories focus on a set of foundational principles, or a set of good character traits.
Aquinas establishes a series of virtues, which define how to live a moral life. He differentiates between cardinal values, and revealed virtues. The cardinal values are taken from Aristotle, who defined twelve such virtues which include prudence, temperance, fortitude and justice. Revealed virtues expand upon (but never contradict) the cardinal virtues, they add laws from the scripture. These are said to be “revealed” virtues because they are not logically deducible. The revealed virtues include faith, hope and charity. In this way God is said to endorse and further natural law, but he does not define it himself – the definition comes from purpose, which...