Natural Moral Law: the foundations in Aristotle and Aquinas, the primary and secondary precepts, the four tiers of law, real and apparent goods, the doctrine of double effect, and strengths and weaknesses of the theory.

What this dot point is asking

You need to explain Natural Moral Law as developed by Thomas Aquinas from Aristotle, including the primary and secondary precepts, the four tiers of law, the distinction between real and apparent goods, and the doctrine of double effect, and then evaluate the theory's strengths and weaknesses. AS 7 is the Religion and Ethics unit, and Natural Moral Law is one of the three normative theories you must be able to explain and apply to medical ethics.

Aristotle, Aquinas and the human telos

For Aquinas, because God created human nature with a purpose, acting in line with that nature is acting morally, and reason is the God-given faculty that lets us read the moral law off our own nature. This makes the theory rational (open to anyone, not just believers), absolutist (its core rules hold always) and deontological (it judges acts by their conformity to the law, not by consequences).

The four tiers of law

Primary and secondary precepts

The heart of the theory is the move from broad purposes to concrete rules.

• Primary precepts are the five fundamental goods that reason identifies as the purposes of human life: to preserve life, to order society, to worship God, to educate the young, and to reproduce. A common memory aid is "POWER" (Preservation, Ordering, Worship, Education, Reproduction).
• Secondary precepts are the specific rules reason derives from the primary precepts. From "preserve life" comes "do not murder" and "do not commit suicide"; from "order society" comes "obey the law" and "do not steal". Secondary precepts are where the theory gains some flexibility, because they are worked out by reason applied to circumstances.

Real and apparent goods, and double effect

The doctrine of double effect allows an action that has both a good and a bad effect, provided four conditions hold: the act itself is good or neutral, the good effect is intended and the bad effect is only foreseen, the bad effect is not the means to the good effect, and there is a proportionate reason. In medical ethics this allows, for example, giving a dying patient pain relief that may shorten life, because the intention is to relieve pain, not to kill.

Strengths and weaknesses

A model evaluation paragraph might run: "Natural Moral Law's great strength is that it is rational and universal: because it grounds morality in a human nature shared by all, it offers clear, stable rules that do not depend on religious belief or shifting opinion, and the doctrine of double effect and the flexibility of the secondary precepts answer the charge that it is merely rigid. Its central weakness is the disputed foundation on which all this rests. The theory assumes that human nature has a single, God-given purpose, yet evolutionary biology suggests human nature is varied and without fixed ends, and G. E. Moore's charge of the naturalistic fallacy claims that one cannot validly derive an 'ought' (how we should act) from an 'is' (how nature happens to be). The judgement, therefore, is that Natural Moral Law offers an admirably clear and consistent framework, but one whose authority stands or falls with a contested view of human nature and purpose."

Try this

Q1. Name the five primary precepts in Natural Moral Law. [3 marks]

• Cue. Preserve life, order society, worship God, educate the young, and reproduce.

Q2. Explain the difference between a real good and an apparent good. [6 marks]

• Cue. A real good fulfils human nature and leads to the telos; an apparent good only seems good and is chosen through faulty reasoning, so no one knowingly chooses evil.

Q3. "Natural Moral Law is undermined by the naturalistic fallacy." Discuss. [12 marks]

• Cue. Explain Moore's claim that you cannot derive an ought from an is, apply it to deriving precepts from human nature, then weigh it against the reply that the theory describes purposes, not mere facts. Reach a judgement.