"When Anu the Sublime, King of the Anunaki, and Bel, the lord of Heaven and earth, who decreed the fate of the land, assigned to Marduk, the over-ruling son of Ea, God of righteousness, dominion over earthly man, and made him great among the Igigi, they called Babylon by his illustrious name, made it great on earth, and founded an everlasting kingdom in it, whose foundations are laid so solidly as those of heaven and earth; then Anu and Bel called by name me, Hammurabi, the exalted prince, who feared God, to bring about the rule of righteousness in the land, to destroy the wicked and the evil-doers; so that the strong should not harm the weak; so that I should rule over the black-headed people like Shamash, and enlighten the land, to further the well-being of mankind."
The notion of divine law has arisen more than once to the East of the Mediterranean. The code of Hammurabi, Mosaic law and sharia each embraces a divine origin and authority for the text it provides. In some cases, such divinely written laws were embedded in a form of holy scripture, such as the Old Testament or the Koran. In others, they were written in stone, as if inscribed by the gods. The implication of the authors of such ancient law codes was that they were channeling the will of God which they were defining for all time.
The division between theologically based law and secular law in the Western models of jurisprudence likely began (and is certainly visible) with the arguments of Ancient Greek philosophers. In the secular model, the sense that morality is an intrinsic but abstract feature of nature allows the application of reason/argument to the realm of law.
With the emergence of ideas of natural law, the notion of a fixed code of rules for all time was gradually replaced by an aspirational model. We are seeking (but never reaching) perfect justice. Human beings codify rules which will change over time as our understanding improves and our situation changes. Nature is the source of universal principles. Law is man-made.
At the end of the medieval period, Thomas Aquinas created a hierarchy for different types of law with God's eternal law at the top and human law at the bottom. His view was that the purpose of man-made law is to expand the common good.
The implication of the secular partition: a form of justice that is circumstantial is necessary. People must aspire to create the laws needed to produce such circumstantial justice but they are not endowed with the ability to write perfect law. Human law is doomed to wear with time. Elements of man-made law might even be unjust. Thus law is subject to evolution and disagreement is permissible.
Enlightenment thinkers went further. They challenged the basic tenet of natural law that the universe has some over-arching benign purpose. Instead, all we have is human law, which is intended to organise a society according to its own purposes and in accordance with its needs.
In many ways, scientific developments run in parallel with the progress of law.
Ancient scientific models explain the universe in terms of scripture (near Eastern creation myths, seven Biblical days of creation etc). Whereas in Ancient Greek cosmology, the underlying principles of natural law were in play (perfect circular orbits, crystalline spheres, ideas of harmonious proportion, the music of the spheres).
These ideas are developed through the classical period. They are usually based on the assumption that earth (and hence mankind) is central and the laws of the universe exhibit some form of divine perfection. Ptolemy produced the geocentric model that was widely adopted in Christendom. Abstract underlying rules founded on classical ideas of the perfection of creation were extended into the metaphysical treatment of light as an expression of the divine (an idea which ended up defining the architecture of Gothic cathedrals) and the notion that where beauty is, there God is also:
"For beauty is the cause of harmony, of sympathy, of community. Beauty unites all things and is the source of all things". - Pseudo-Dionysus
In the late medieval period, this divine model of the universe is first run in parallel with the computational/heliocentric explanations of Copernicus and then replaced by the calculations of Kepler and the observations of Galileo. The sense of divine purpose in the architecture of creation is removed in favour of the notion of the machinery of existence, which just is.
Science doesn't limit itself to cosmology, of course. It is interested in life above all. Darwin explains the evolution of life in scientific terms as a process of survival through modification in the face of contingent circumstances. In the twentieth century we discover DNA and see its instructions as the primary force of variation in life.
Mysteries remain. But in both the laws of man and of nature, no divine explanation is necessary. Although it is beautiful in our eyes, the universe does not seem designed to be benign. Nor is there is a set of perfect principles of justice designed to encompass all situations for all time.
And yet we choose altruism as our brightest virtue. Indeed, curiously, in the way mathematicians view game theory, in the way populations cooperate, in the way economics produces efficiency, it seems intrinsic.
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