Natural law is divided into two different aspects. There is the natural law theory of morality which dictates what is right and what is wrong and there is the natural law of positivity which dictates what is legal and what is illegal. These two aspects of natural law are independent of each other. The two aspects carry rival views of what is law and the relationship between law and justice. The function of any legal entity is to safeguard justice. Legal systems have a function to secure justice. Everything including non-living things has their purpose for existence, and the fulfillment of anything is the achievement of its function. The fulfillment for people is their entire happiness. Entire happiness is in our nature; it is in what we humans do best. Human beings have virtues that help in fulfilling their true nature. Natural law is, therefore, a set of truths about morality and justice that human beings must follow to live a good happy life. As such, acts of immorality are against natural law and are therefore considered unnatural where unnatural means they are opposite to our purpose. In the same light, virtuous behavior is natural where natural means it is in-line with its purpose. Unjust laws are not considered to be laws, but serious perversions of law and are unnatural. Therefore, there is no moral authority or obligation to obey unjust laws. Natural law theory has many criticisms. One of the major criticisms is that for natural law theory, the term “nature” can easily be taken to mean different things by different people and by different circumstances. This should not be the case if the natural law theory is known by natural human reason. Another problem concerns how we can determine the most important characteristics of human nature. If human beings are found to be essentially selfish, therefore one can easily conclude that lying is morally right. According to Aquinas, the order of natural moral law theory is there because God has put it there. It, therefore, is consistent that for the law to hold its water there has first to be the belief that God exists and rewards those who seek Him. But, then, what about those who do not believe in the existence of God? (Finnis, 2001) Natural law falls short again in establishing laws for the acceptable behavior for human beings and in the same way establish laws for the behavior of animals. This is inconsistent with human behavior is shaped by his environment such as training and education which can be deliberate or not deliberate. Law is expressed as the desire to do something backed by a legal use of force or a threat of punishment. The source is an essential part of anything. For a particular rule or law to have a legally binding obligation for human beings to comply with it, it has to come from a valid source. This means that for a law to be valid, it has to come from a source which is from a certain person or group of people such as kings or governments. This person or group of people or institution has to be obeyed or revered by many people living in a particular area, and this person does not obey anyone else. The law has to be in accordance with certain procedures that the society upholds. A rule can be put in place and enforced even though it is seriously unjust. It follows that to have a legal right to perform a certain action or deed does not mean that one has a moral right and the opposite holds true that for one to have a moral right does not mean that the action is legal. One can have the legal right to do what is morally wrong such as the right to own a slave. The issue of legality is considered a completely separate issue from moral issues. Legality is therefore separable from morality. This creates a very simplistic law. A problem emerges when a society’s member is the supreme and gets to set the rules that prevail over ordinary cases of conflict and setting boundaries of validity such that establishing priorities and canceling invalid norms are made by an official who posses great authority. Although it is acceptable in the society, and is accepted as being legal by some of the people whom they apply to it creates a legal bias especially in issues affecting the authority. Also the creation of separation of morality and legitimacy creates another issue (Gardener 2001). There are basic rules that inform persons on what they are required to perform in regard to certain actions or prohibiting of certain actions and then there are rules that provide persons to have liberty to take those rules and modify their functioning and limit their scope. This may create a variety of duties and obligations. Therefore, Barbeis (2016) notes that only a society of closely knit people can live under this rules. If doubts arise as to what the rules are or as to the precise scope of some given rule, there will be no procedure for settling this doubt, either by reference to an authoritative text or to an official whose declarations on this point are authoritative. Natural law argues that each object is essentially material, formal, and efficient and has purpose. This reasoning, when applied to reproduction in human beings, brings out the point that giving birth is the natural purpose whereas abortion is the counteractive therefore unnatural and as such a wrong choice or action. Therefore according to natural law, abortion is wrong. Natural law further argues that we, human beings, have the God given intellect to make decisions on moral issues. Also, there is the belief that we are created in God’s image and what this essentially means is that morally abortion is forbidden as it means ending life. For natural law, life both in the womb and outside the mother’s womb holds the same and equal value. This, therefore, means abortion is equal to murder. Abortion, furthermore, goes against the core principles of natural law of reproducing and the preservation of life (George 2000). However, according to the natural law, there is a circumstance that makes abortion legal and right in the eyes of the law. This is through the doctrine of double effect. The doctrine states that an action that has an unnatural result, an immoral outcome, can be allowed and performed if the action is not intended and the result of the outcome is not the intended objective. This is to say that if a woman is found to have complications that threaten both the life of the child and the mother, an abortion can be procured to save the life of the mother. The objective is therefore to save the mothers life, and the secondary outcome is the murder of the child. A case where this can be applicable is in an instance of ectopic pregnancy. The natural law, which was propagated by St. Thomas Aquinas, follows that there is a direct relation between moral behavior and a supreme being known as God who created the whole universe and everything in it. The natural law is a code of conduct that was instilled in human beings as a legal framework to help mankind live and build their societies around these concepts. Natural law further demands that in instances where there is a conflict between the moral code and man-made laws, the natural law takes precedence as the natural law is made to enhance the common good in the society. It further follows that a law that does not promote the common good is an unjust law and should therefore not be followed. The concept of legal positivism, on the other hand, opposes the notion that morality and legality are connected and therefore separates the two concepts. It further states that laws are made by human beings for the use by human beings. It states clearly that legal entities are manmade and therefore are not good or bad in consideration to morality. The laws are formulated by persons that have total authority over the people in a region where they govern. The persons uphold legislation by use of force or threats of punishment. This use of force and threats of punishment make subjects to comply with laws whether they are good or bad.References Barberis M & Bongiovanni Giorgio (2016). Neoconstitutional Challenges to Legal Positivism. Springer NetherlandsFinnis, J. (2011), Natural Law and Natural Rights 2nd edn. Oxford: Oxford UP.Gardener,J(2001). Legal Positivism:51/2 Myths. 46 America Journal of jurisprudence.George, R. & Wolfe, C. (2000)Natural Law and Public Reason. Kluwer P.