“The laws of nature, as analyzed mathematically and descriptively by Ptolemy and Galen, bore an interesting, and perhaps not entirely accidental similarity to the law of nations and of nature, as discerned by a long succession of Roman jurists. …The concept of an objective law applicable to human affairs, yet operating in accord with Nature and Reason and apart both from divine revelation and from human whim or passion, was peculiar to Rome and societies descended from Rome.”

Six Principles of Political Realism http://www.mtholyoke.edu/acad/intrel/morg6.htm, § 1.
Politics Among Nations (1948)
Context: Political realism believes that politics, like society in general, is governed by objective laws that have their roots in human nature. In order to improve society it is first necessary to understand the laws by which society lives. The operation of these laws being impervious to our preferences, men will challenge them only at the risk of failure.
Realism, believing as it does in the objectivity of the laws of politics, must also believe in the possibility of developing a rational theory that reflects, however imperfectly and one-sidedly, these objective laws. It believes also, then, in the possibility of distinguishing in politics between truth and opinion — between what is true objectively and rationally, supported by evidence and illuminated by reason, and what is only a subjective judgment, divorced from the facts as they are and informed by prejudice and wishful thinking.

28 May 1794
On the Impeachment of Warren Hastings (1788-1794)

governing their formation
As quoted in "On 'computabilism’ and physicalism: Some Problems" by Hao Wang, in Nature’s Imagination (1995), edited by J. Cornwall, p.161-189

"Why the Land Belongs to Bundy," http://www.economicpolicyjournal.com/2014/04/why-land-belongs-to-bundy.html Economic Policy Journal, April 25, 2014.
2010s, 2014

Thus writes Blackstone, to whom let all honour be given for having so far outseen the ideas of his time; and, indeed, we may say of our time. A good antidote, this, for those political superstitions which so widely prevail. A good check upon that sentiment of power-worship which still misleads us by magnifying the prerogatives of constitutional governments as it once did those of monarchs. Let men learn that a legislature is not “our God upon earth,” though, by the authority they ascribe to it, and the things they expect from it, they would seem to think it is. Let them learn rather that it is an institution serving a purely temporary purpose, whose power, when not stolen, is at the best borrowed.
Pt. III, Ch. 19 : The Right to Ignore the State, § 2
Social Statics (1851)

For My Legionaries: The Iron Guard (1936), Politics

The Way Into The Holiest (1893)

Source: Psychology: An elementary textbook, 1908, p. 44

Opening lines, p. 104
Variant translations:
What is God-given is called nature; to follow nature is called Tao (the Way); to cultivate the Way is called culture.
As translated by Lin Yutang in The Importance of Living (1937), p. 143
What is God-given is called human nature.
To fulfill that nature is called the moral law (Tao).
The cultivation of the moral law is called culture.
As translated by Lin Yutang in From Pagan to Christian (1959), p. 85
The Doctrine of the Mean