Aquinas argued that the first priority laid down by natural law concerned ‘self-preservation and the preservation of the innocent’. He also declared four additional ‘primary precepts’ including the ‘continuation of the species through reproduction’, the ‘education of children’, to ‘live in society’ and to ‘worship God’, which conform to the main purpose of human nature. However, he also acknowledged four ‘secondary precepts’ (do not murder, do not abort unborn, defend the defenceless and do not commit suicide) which are further rulings that human beings should avoid, as they do not uphold the primary precepts.
It is also important to confirm that Aquinas distinguished ‘interior acts’ from ‘exterior acts’ and regarded the former of higher importance; an act may be good in itself (exterior concept) but undertaken for the wrong intention (interior concept) – for instance giving to charity may be good in itself but if it is done in order to attract praise then there is a bad intention.
The theory of natural law can applied to various situations. However, it is important to clarify that the concept of this theory is primarily concerned with the ‘act’ and does not take into account the consequences or situations (such as Utilitarianism). For example, Peter Vardy uses the illustration of a woman with heavy periods. If the doctor were to prescribe her the ‘pill’ to stop the pain then the fact that this would also act as contraception is a fortunate consequence and nothing more; it would be seen as acceptable because the purpose of the pill was to stop pain not prevent fertilisation.
It is clearly evident that the strengths that can be ascribed to natural law are a product of its absolutist deontological view of morality. This is to say that it enables people to establish common rules in order to structure communities, which can be viewed upon as an attractive option in our current society, which at present, consists of a relativist era that is suffering from a break down in traditional social structures and moral uncertainty. Furthermore, Aquinas’s view of reason as a tool for moral understanding and his idea of a common nature and morality for all people gives natural law a universality that goes beyond any one religion or culture. This can be seen as a very positive aspect considering the intercultural strife and disharmony that exists between cultures and societies (i.e. the middle-east) which all uphold similar basic principles such as conserving life.
Moreover, natural moral law gives a concrete reason to be moral and provides a firm basis for individuals to refuse to cross moral boundaries. It also provides justification and support for those ideas popular in today’s world such as human rights, whilst condemning actions such as torture, irrespective of consequences. Natural law also provides a way of living, giving guidance on day-today questions of how to live life and then links them to the fundamental principles of life, while avoiding the ambiguities in systems that involve assessing consequences, such as Utilitarianism.
However, the weaknesses of natural law are equally apparent, the largest of which being the ‘Naturalistic Fallacy’. This theory suggests that we should apply information obtained through scientific observation, what life ‘ is’ like, to how we ‘ ought’ to behave. G E Moore considered this jump from scientific observation to moral behaviour to be illogical and declared: “Defining the ‘good’ can’t be done, because good is a simple property. We may list any number of other things or qualities which possess the property good, but thinking of any of these as the only good, or defining good by means of any of these things, commits the naturalistic fallacy..”.
It is also evident that many dispute the presence of a common law (and whether humans have a single nature), and argue that Aquinas’ interpretation of the precepts in incorrect, which would bring into question the idea of a ‘human purpose’.
In addition, it is significant to declare that natural law is a Christian ethic, yet Jesus’ opposition to legalistic morality is apparent in the New Testament, and therefore it can be argued that Jesus rejected this approach to morality (this view is supported by Joseph Fletcher). I would also like to take this opportunity to make reference to Proportionalism which is an ethical theory developed to provide a more balanced approach between Christian natural law and the modern relativist Christian ethic – situationism.
In conclusion, in trying to decide if natural law can be held as a definitive ethical theory one has to realise that although the theory isn’t as rigid as it first appears (i.e. the secondary precepts may change in particular aspects) it is still faced with problems, which may well, be insurmountable. The conclusions of the Roman Catholic Church regarding the prohibition of activities such as artificial contraception and homosexual acts can be subject to convincing challenge. It is also important to note that in the absence of clear guidelines it is impossible to know definitively what is and what is not natural and so therefore rendering the issue entirely subjective. Once an issue becomes subjective (based on a person’s emotions and prejudices), and it is difficult to produce an instance when subjectivity would be absent, and therefore I regard natural law as a failure of a definitive ethical theory.
