Natural law is an absolutist theory. According to said theory there are easily definable moral absolutes; both right and wrong discovered through reason and observations. These codes are the same in all religions, cultures and times. The laws do not take into account relative situations and do not change to fit the circumstances in which they may be more helpful. The natural order is determined by a supernatural power-most commonly referred to as God. The laws are independent of public opinion and are unchangeable.
The natural law exists to assist humans to direct their actions in such a way that they will reach their final purpose and eternal destiny with God. The natural law theory was developed by St Thomas Aquinas. He was an absolutist and deontological theorist. This means that he believed that actions were intrinsically right or wrong, irrespective of their consequences. He worked through the 12th century bringing different ideas from different cultures together. His work was heavily influenced by a Greek philosopher Aristotle.
The mediaeval church rejected Aristotle’s ideas, as they believed he was trying to replace religion with reason, which the natural law’s basic ideas lie on. However Aquinas showed that if human reason is acknowledged to come from God then faith and reason can provide people with the best tools for living. He said that our reason could be a guide to our virtues and if we follow our reason, others would not suffer, or would suffer less. Aquinas believed that everything existed for a reason, and had a purpose.
He believed that something could be called ‘good’ if it fitted its purpose. If there was a knife, then its purpose would be to cut. A blunt knife would have little reason to survive as it did not fulfil its purpose, however a sharp knife would cut well and its reason for being in the world is to do so. He said that ‘something is good if it does whatever God wanted it to do’. Aquinas distinguished his causes as the ‘efficient cause’ and the ‘final cause’. The efficient cause is that which gets things done and the final cause is the product or the outcome.
Aquinas believed that the world has God’s ultimate purpose as its final end or good. A human’s purpose of existence does not just lie in this life; we have been given reason and freedom and can choose to follow Natural Law. Aquinas presupposed that humans were created by God on purposefully. They have to work out what their purpose is and then aim to fulfil it, if we do, then we are good. Aristotle said that everyone was born with the potential to do something, but many fail to realise it. ‘Potentiality’ refers to the possibilities of change that something has.
For example, someone may not be good at the piano but after many years of lessons they could become a brilliant concert pianist. This is turning potentiality into actuality which is the essence of goodness. Today the Roman Catholic Church uses the views that were adopted from Aquinas. They believe that Christian faith could be shown to be not just a matter of blind faith, but reasonable and logical, fit for intelligent people. For example the church reject the idea of abortion, as although the baby is not fully developed there is the potentiality of life and we should not be allowed to stop the actuality of it.