Natural law ---
Intro
Natural law, which is the subject of the question, is an enduring concept in jurisprudence, ranging from Aristotle, who held that there is a natural law which ‘everywhere possesses the same authority and is no mere matter of opinion’, through Cicero, who taught that ‘Nature herself has placed in our ears a power of judging’, and Aquinas for whom the natural law was ‘the participation of the eternal law in the rational creature’, to today’s natural lawyers such as John Finnis who view law from the perspective of its ultimate moral function which is taken to be the ability of law to co-ordinate human activity for the common good. Natural law is often contrasted with the ‘positive law’, namely, the legal rules promulgated in formal fashion by the state and enforced through defined sanctions. A problem for students is to decide which ‘type’ of natural law is being referred to, since the term has been used in so many different senses. It is essential, therefore, to check the ‘precise historical and juristic context’ of the term, particularly when answering questions on this topic.

Checklist:
Natural and positive law contrasted
Natural law as an aspect of Divine providence
Aquinas’s divisions of law
The link between natural law and modern legal systems (the ‘common good’ view of law)
Finnis’s self-evident human goods.
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What is Aquinas’s theory of law?
Thomas Aquinas (1225-74) was concerned with systematising knowledge, on the basis of Catholic doctrine, so that the cosmos might be understood as a vast unit in which everything had a place and a meaning. Within this system of knowledge, God’s plans for mankind occupied a special place, and the law was to be comprehended as a part of those plans. Aquinas propounded a theory of law based on his conception of ‘reason’, this resulted in a fourfold division of law in which so-called ‘natural law’ is of much significance. The answer given below is based on the following skeleton plan:
Ans:
ST Thomas Aquinas occupies an important place in the history of the development of natural law doctrine. He had studied as Dominican monk under Alberyus Magnus and, in later years, produced works of lasting significance in which he effected a synthesis of the logic of Aristotle, the religious thought of the early Christian Fathers, and some of the patterns of classical Roman law. In his celebrated ‘Summa Theological (c1266)’ he set out a fully systematised approach to law which, even today, dominates the thinking of many Catholic jurists, as evidenced by the growing neo-Scholastic school of jurisprudence. Law is to be understood as part of God’s plan for mankind-this is the belief which is central to the concepts mentioned below.
It is important to remember the context within which Aquinas worked. The authority of the Catholic Church was expanding, and those whose task it was to explain doctrine were guided by a strict pattern of thought, Interpretation of the Scriptures had produced two principles which were of direct relation to attempts at explaining the nature of law. First, the principle of ‘unity’ (based on ‘one God, one Church’) was reflected in the wish for ‘one Church believing in one law’. Secondly, the principle of ‘supremacy of law’, which was seem as an aspect of the unity of the world, taught that all persons, including rulers, were under the law’s dominion. Aquinas’s general approach to law was fashioned with these principles in mind.
At this time, a study of the works of Aristotle was not always welcomed by the dominant church hierarchy, which viewed his ‘scientific rationalism’ as a potential threat to church dogma. Aquinas did not share this attitude. He was deeply impressed by Aristotle’s emphasis on reason and the primacy of intelligence, and was affected profoundly by their elucidation of the part that could be played by reason in the understanding of phenomena such as law.
In the ‘Summa Theological Aquinas’ seeks to establish the