Natural Law

  • Created by: joshway99
  • Created on: 17-02-16 18:38

Background Information

Thomas Aquinas

He was born in Aquino, Italy in 1224 CE. He was an important Christian philosopher and theologian. He developed a fuller account of natural law in the 13th Century.

At age fourteen he studied the liberal arts at the University of Naples. At this university he was exposed to the work of Aristotle. He used Aristotle’s work to show that Aristotle’s arguments could serve to support Christian beliefs.

He wrote a book called ‘Summa Theologica.’ In this book he described natural law as a moral code existing with the purpose of nature, created by God. His ethical theory was absolutist, legalistic and deontological.

He died at the age of 49 in 1274.

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Aquinas' Work

He used Aristotle’s work and put it into a Christian belief. Aquinas supported efficient and final cause and he said that everything had a purpose and this purpose was given by God. Four universal (applicable at all times) and eternal (forever) laws that Aquinas identified included; Eternal – God, Divine – sacred texts, Natural – right and wrong and human – human law (legal system). He also said that unique function of man was the ability to reason. This ability to reason is from God. Aristotle’s work was considered dangerous by the Roman Catholic Church, but Aquinas still used them to show that Aristotle’s argument could support Christian beliefs.

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Background Information

Natural Law

Natural law = this is concerned with the moral law of how human beings should behave. It is understood by reflecting on human and nature and rationally working out what leads to happiness.

Background Summary

In the 13th Century crusaders returned from the East and they brought copies of the works of Aristotle. Aristotle was a Greek philosopher writing from a non-religious perspective. Aquinas used these ideas to support Christian beliefs. The Church viewed these ideas with suspicion but eventually realised that Aquinas made good sense. This was because they could no longer appeal to scripture alone for authority due to rise of Islam.

Aquinas’ work became the official teaching of the Roman Catholic Church in 1879.

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Background Information (Continued)

Natural law can be defined as;


The idea that people should obey religious laws in order to be good.


Acts are intrinsically good – good within themselves. You don’t commit the action for the consequences.


Laws are the same regardless of the situation.

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Background Information (Continued)

For Aristotle, he believed that there was a law written in nature for humans to know how to act morally. He also believed that following these laws would lead to Eudemonia. Eudemonia is successfully fulfilling your purpose which leads to being happy. Aquinas was heavily influenced by this, and he believed that humans lean towards the good. Aquinas also said that eudemonia would be a reward in heaven for good actions on Earth.

Another thing that influence Aquinas was Aristotle’s belief that all humans have a purpose (telos). For Aquinas this was a God given ideal purpose. Similar to Aristotle, Aquinas believed that all humans possess the unique ability to reason. He says that this is a God given reason and it helps humans identify how to act morally. The use of our reason reveals to us the ultimate ‘goods’ in life.

The ultimate aim or final purpose for every human is to re-establish a ‘right’ relationship with God and by doing so gain eternal life. For Aquinas, fulfilling our purpose will lead us to the ‘final cause.’

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Background Information (Continued)

The moral codes are perceived by all humans, although only believes in God acknowledge that it has implications for them beyond the grave. The moral codes is;

Accessible through the natural order

Universal – all around the world

Unchanging – eternal

For all time

Relevant to all circumstances

Given by God – divine law

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Exterior and Interior Acts

This natural law exists to help humans to direct their actions in such a way that they may reach their eternal destiny with God. Aquinas said that there was a basic law, or precept (purpose / reason), within which all the other natural laws play a part.

Basic law = good is to done by and pursued and evil is avoided. All of the other precepts of the law of nature are based on this.

For Aquinas, both the intention and the act are important. To act in a good way for the wrong reason is to perform a good exterior act but a bad interior act. For example to help an old lady across the road (good exterior act) to impress someone (bad interior act) is wrong. It should be done out of charity and not for the sake of admiration of others.

Aquinas believes that acts are intrinsically good or bad because when humans act in accordance with their ultimate purpose, God is glorified.

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Faith and Reason

Aquinas believed that reason was God’s gift to humanity and that humankind’s purpose could be identified through the application of reason. Aquinas stated that humans are created to serve God just like other creatures.

Reason = we can our final cause (Telos / purpose) and then choose to follow it or not.

The eternal law of divine reason is perceived in two ways;

Through revelation, in the form of the word of God (the Bible). Aquinas accepted that the Bible is divine law revealed by God, he accepted it as literal truth. However, we can also discover the same moral truths by using our reason. This possibility is open to all humans. You don’t need to be religious to understand natural law.

Through human reason. Aquinas claims that we are designed by God to be rational creatures, we need to use this ability to work out for ourselves the truths about God that are contained within the created order.

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Faith and Reason (Continued)

A moral life is a life lived according to reason – an immortal life is lived at odds with reason.

This reasoning determines that the ultimate purpose and destiny of human life is fellowship with God. People must avoid being enslaved by non-natural, non-rational desires.

Aquinas says that humans will only find true fulfilment in life when they choose to serve God because by doing so they will be doing what they were created for.

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Aquinas argued that there was link between happiness and virtuous behaviour; reason can guide people in developing the right virtues. These virtues (positive characteristics) are important because they represent the qualities that help us live a moral life and therefore fulfil our true human nature, this then leads to eternal life with God.

Virtue = comes from the Greek word “arête” which means excellence in terms of personal qualities.

Cardinal virtues = comes from the Latin word “cardo” meaning hinge – all other virtues hinges on these, they are of fundamental importance.

Aquinas outline four human qualities he believed to be necessary to form the basis of a moral life. They are also found in the writings of Aristotle. The four cardinal virtues are;

Prudence = ability to judge between actions / wisdom. Justice = balance our interests with the rights and interests of others.

Fortitude (courage) = ability to confront fear in order to achieve ones goals. Temperance = self-control or restraint in order to be considered honourable.

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Primary Precepts

Worship God - Humans question their origins. For Aquinas this means, they want to know God. Therefore, it is natural to be inclined towards worshipping God.

Ordered Society - Who likes arguing? Most people seek to resolve disputes and want to live peacefully.

Reproduce - It is natural to want to have sex, our hormones have an effect on our bodies, which makes us desire it. It makes sense to bring up children in a sable, lawful relationship e.g. marriage.

Learn - Humans have an inclination to want to know everything there is about the universe. It makes sense for each one of us to seek education.

Defend the Innocent - It is natural to create conditions to keep ourselves fit and healthy and avoid situations which threaten life (preserved life).

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Secondary Precepts

Secondary precepts are rules about things that we should or should not do because they uphold, or fail to uphold, the primary precept. Natural law identifies two secondary principles under the primary principles, these are;

Self-evident rules needed to uphold the primary precepts e.g. do not murder, respect your parents.  Rules coming from a more complex process of reasoning, an example of this would be; Reproduction is a primary precept, the purpose of human genitals is reproduction, therefore, masturbation and homosexuality are wrong because they don’t lead to new life and they don’t fulfil their purpose and don’t glorify God. But having heterosexual intercourse is good because it involves using genitals for their purpose, to pursue the primary precept of reproduction and this action glorifies God.

All things must operate in accordance with these principles, to which humans are naturally inclined. God gives human the power to reason to accomplish these purposes, whether they believe in him or not, and everything is created to a particular design and for a particular purpose; fulfilling this purpose is ‘good’. 

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Principle of Double Effect

Aquinas stated that even if a good act which has an intended good effect has secondary bad consequences, it is still right to carry on this act. This is known as the principle of double effect. The thing that is important is your intention when performing the act and you cannot be held responsible for any unintended consequence of an act.

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Real and Apparent Goods

Aquinas believed that human nature was essentially good, as natural law is within everyone. Humans were oriented towards the achievement of perfection and they could never knowingly pursue evil, but rather their use of reason was misguided. He recognised that not everyone clearly perceives what is good. For example, some people don’t have a guilty conscience about making false accusations or about stealing. This is because their desires and emotions override their rational sense of right and wrong and their ability to think virtuously.

Real good = a characteristic that will help people become closer to the ideal human nature that god has planned for them.

Apparent good = a vice or sin that takes people further away from the ideal human nature that God has planned for them.

Sins consists of falling short of God’s intentions for humans. To choose an apparent good is an error. To correctly distinguish between apparent and real goods is to use reasoning rightly and to choose the right thing to do. It isn’t necessarily easy, as we’re tempted by what we like doing, which may not be was is truly good for us.

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Seven Deadly Sins

The Seven Deadly Sins are;

1. Pride

2. Avarice (Greed) - Money

3. Lust

4. Envy

5. Gluttony (Greed) - Food

6. Anger

7. Sloth

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Four Causes

Aquinas agreed with Aristotle’s views on how we determine a “things” purpose. Aristotle believed that knowledge could be sought and found directly from the world of the senses. He also argued that everything that exists has a purpose and if it ‘performs according to its natural intended purpose then it comes ‘virtuous’ or good. In other words, it is fulfilling its function. He says that everything has a goal or ‘telos’ and its purpose is to achieve this goal. For Aristotle everything has four ‘causes’ (which bring it into existence) these include;

1)  The material cause – what something is made of

2)  The efficient cause – the force that brings it into being

3)  The formal cause – the idea

4)  The final cause – the purpose of the thing.

For Aquinas, God is the efficient cause. The primary and secondary precepts helps is live in a way that brings us closer to our final cause (to mend the broken relationship with God). The primary precepts are absolute. We must use our reason to work out the secondary precepts which enable us to achieve the primary precepts. 

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Compatible with Christianity

Aquinas was Christian / priest

The motive for committing an act is important as well as the act (Matthew 6 v2)

It reflects Christian teachings

People sometimes fall short of God’s purpose and sin (John 8 v1-11)

Primary precepts are reflected in the Bible

Goal of every human is to return to God

Absolute laws are recognised as eternal and understood / maintained by divine laws

Teaches God created the world and established a sense of purpose / order

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Non-Compatible with Christianity

Jesus told people to love one another as I have loved you. Natural law is based on reasoning

It conflicts with teachings of Jesus such as turn the other cheek, natural law would allow one to break this teaching in order to                        preserves one’s own                    life

Primary precepts will gain rewards in heaven according to natural law. Jesus said that good actions, should be done for their own sake

Examples in the New Testament where Jesus rejects the legalistic laws of the day

Some people question the idea that there is a universal human nature e.g. gay religious believers would argue that God created them this way

Some denominations such as the Quakers rejects the absolute approach to issues such as homosexuality

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It’s absolutist and deontological, this makes it a strength because it provides clear-cut rules.

It’s based upon human ability to reason and doesn’t rely on unpredictable consequences or emotions.

It creates a link between the creator, our creation and our purpose.

It is simple to follow as it assumes that there is an ideal and universal human nature all humans need to do is strive towards this state.

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Many people would question the idea that there is a universal human nature.

A non-believer would      have no desire to follow a system of ethics based upon a belief in a creator God and fulfilling God’s will

Not all rational people agree with natural law and not everyone bases their moral choices on reason

It fails to consider the situation people find themselves in or the consequences of an action.

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