Natural Law says that everything has a purpose, and that mankind was made by God with a specific design or objective in mind (although it doesn’t require belief in God).  It says that this purpose can be known through reason.  As a result, fulfilling the purpose of our design is the only ‘good’ for humans.

  • Created by: Alex
  • Created on: 12-04-11 11:18

The Theory of Natural Law

The theory of Natural Law was put forward by Aristotle but championed by Aquinas (1225-74).   It is a deductive theory – it starts with basic principles, and from these the right course of action in a particular situation can be deduced.   It is deontological, looking at the intent behind an action and the nature of the act itself, not its outcomes.

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The purpose of humans - the Primary Precepts

In four words, 'Do good, avoid evil'. In more detail, Aquinas talked of Primary Precepts. Whilst you probably think of Natural Law as a deontological position (deon- duty; deontological ethical positions have absolute rules that it is our duty to follow), this part is teleological. Telos- purpose. What is our purpose - what are we designed for? What follows is an acrostic, which I have arranged so it makes a word. Some of my students favour PROWL, as 'protect and preserve the innocent' should, they argue, come first. I prefer WORLD...

  • Worship God
  • Ordered society
  • Reproduction
  • Learning
  • Defend the innocent
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Secondary Precepts

These are the rules - absolute deonotological principles - that are derived from the Primary Precepts. For example, the teleological principle "Protect and preserve the innocent" leads to rules such as "Do not abort," "Do not commit euthanasia" etc. These rules cannot be broken, regardless of the consequences. They are absolute laws.

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‘Efficient’ and ‘Final’ Causes.1.

This is Aristotle’s distinction between what gets things done (efficient cause) and the end product (final cause).   With humans, it is the accomplishment of the end product that equates to ‘good’.  An example is sexuality – an efficient cause of sex is enjoyment: because humans enjoy sex, the species has survived through procreation.  However, the final cause of sex (the thing God designed it for) is procreation.   Therefore sex is only good if procreation is possible.

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‘Efficient’ and ‘Final’ Causes.2.

Put another way, the efficient cause is a statement of fact or a description.  If we ask why people have sex, we might talk about attraction, psychological needs etc.    The final cause is a matter of intent – what was God’s purpose behind sex?  The final cause assumes a rational mind behind creation, and as such moves from descriptive ethics (saying what is there) to normative ethics (statements about what should or should not be the case).

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‘Efficient’ and ‘Final’ Causes.3.

Another example – did the soldier shoot well?  The efficient cause deals with the set of events around the shooting – did he aim well, was the shot effective, did the target die?  These are descriptive points, and clearly don’t tell us about the morality of the shooting.   When we look into this area – was it right to kill? -  we are evaluating his intent, and are asking about the final cause.  We can then look at whether that cause is consistent with God’s design for human beings.   We may decide that killing innocent people goes against God’s design for us, so it is always wrong to kill innocent people.

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Real and Apparent Goods

Aquinas argued that the self should be maintained.  As a result, Natural Law supports certain virtues (prudence, justice, fortitude and temperance) that allow the self to fulfil its purpose.  Similarly there are many vices (the seven deadly sins) that must be avoided as they prevent the individual from being what God intended them to be.

Following a ‘real’ good will result in the preservation or improvement of self, getting nearer to the ‘ideal human nature’ that God had planned.  There are many apparent goods that may be pleasurable (e.g. drugs) but ultimately lead us to fall short of our potential.   Reason is used to determine the ‘real’ goods.

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Aquinas believed in life after death, which leads to a different understanding of God’s plan for humans.  Natural Law can be upheld by atheists, but there seems no good reason for keeping to Natural Law without God.   Aquinas holds that the one goal of human life should be ‘the vision of God which is promised in the next life’.  This is why humans were made, and should be at the centre of Natural Law thinking.

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Causistry and Double Effect

Causistry is the name given to the process of applying Natural Law principles to specific situations.   This is done in a logical way, as some principles have logical consequences.  For example, if it is in principle wrong to kill innocent human beings, it follows that bombing civilian targets (such as Dresden in WW2) is wrong.  However, if it is accepted that killing in self defence is okay, we could justify an air attack on Afghanistan on these grounds.  Innocent people might die, but that is not the aim of the action, so the doctrine of double effect comes in to play. 

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Causistry and Double Effect.2.

Double effect refers to situations where there is an intended outcome and another significant but unintentional outcome.  According to Natural Law, it is our intentions that are important, not the consequences of our actions. Double effect would not allow you to perform an action where an unintended outcome had devestating effects. The unintended effect has to be PROPORTIONATE. What this actually means, critics say, is that Natural Law becomes like Utilitarianism.

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