“There is a written and an unwritten law. The one by which we regulate our constitutions in our cities is the written law; that which arises from customs is the unwritten law.”

The Law
The Note-Books of Samuel Butler (1912), Part VII - On the Making of Music, Pictures, and Books
Context: The written law is binding, but the unwritten law is much more so. You may break the written law at a pinch and on the sly if you can, but the unwritten law — which often comprises the written — must not be broken. Not being written, it is not always easy to know what it is, but this has got to be done.

Thomas Taylor (Tr.) Political fragments of Archytas, Charondas, Zaleucus, and other Ancient Pythagoreans, preserved by Stobæus; and also, Ethical Fragments of Pierocles http://books.google.com/books?id=Kx4PAQAAMAAJ (1822)

Silence is a Commons (1982)
Context: "Commons" is an Old English word. According to my Japanese friends, it is quite close to the meaning that iriai still has in Japanese. "Commons," like iriai, is a word which, in preindustrial times, was used to designate certain aspects of the environment. People called commons those parts of the environment for which customary law exacted specific forms of community respect. People called commons that part of the environment which lay beyond their own thresholds and outside of their own possessions, to which, however, they had recognized claims of usage, not to produce commodities but to provide for the subsistence of their households. The customary law which humanized the environment by establishing the commons was usually unwritten. It was unwritten law not only because people did not care to write it down, but because what it protected was a reality much too complex to fit into paragraphs. The law of the commons regulates the right of way, the right to fish and to hunt, to graze, and to collect wood or medicinal plants in the forest.
An oak tree might be in the commons. Its shade, in summer, is reserved for the shepherd and his flock; its acorns are reserved for the pigs of the neighbouring peasants; its dry branches serve as fuel for the widows of the village; some of its fresh twigs in springtime are cut as ornaments for the church — and at sunset it might be the place for the village assembly. When people spoke about commons, iriai, they designated an aspect of the environment that was limited, that was necessary for the community's survival, that was necessary for different groups in different ways, but which, in a strictly economic sense, was not perceived as scarce.

Wason v. Walter (1868), L. R. 4 Q. B. 93.

Reception in Winder, Georgia, September 11, 2003. http://renewamerica.us/archives/speeches/03_09_11reception.htm.
2009

Speech, United States Senate (11 March 1850).
Context: It is true, indeed, that the national domain is ours. It is true that it was acquired by the valor and with the wealth of the whole nation. But we hold no arbitrary authority over it. We hold no arbitrary authority over anything, whether lawfully acquired or seized by usurpation. The constitution regulates our stewardship; the constitution devotes the domain to union, to justice, to defense, to welfare and to liberty.
But there is a higher law than the Constitution, which regulates our authority over the domain, and devotes it to the same noble purposes.

Book I, Chapter I; slightly modified translation from Norman T. Pratt Seneca's Drama (Chapel Hill: University of North Carolina Press, 1983) p. 140
Controversiae

Assistance
Poetry quotes, New Thought Pastels (1913)
Context: Look to the Great Eternal Cause
And not to any man, for light.
Look in; and learn the wrong, and right,
From your own soul's unwritten laws.
And when you question, or demur,
Let Love be your Interpreter.

Source: Law and Authority (1886), II
Context: Relatively speaking, law is a product of modern times. For ages and ages mankind lived without any written law, even that graved in symbols upon the entrance stones of a temple. During that period, human relations were simply regulated by customs, habits, and usages, made sacred by constant repetition, and acquired by each person in childhood, exactly as he learned how to obtain his food by hunting, cattle-rearing, or agriculture.
All human societies have passed through this primitive phase, and to this day a large proportion of mankind have no written law. Every tribe has its own manners and customs; customary law, as the jurists say. It has social habits, and that suffices to maintain cordial relations between the inhabitants of the village, the members of the tribe or community. Even amongst ourselves — the "civilized" nations — when we leave large towns, and go into the country, we see that there the mutual relations of the inhabitants are still regulated according to ancient and generally accepted customs, and not according to the written law of the legislators.