An idea called “natural law” or “the law of nature” runs through all political and social philosophy. Natural law is not written down, but it is the standard by which “justice” and “goodness” are measured. Natural law provided the American colonies with a justification for their revolution:

When in the course of human events it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth the separate and equal station to which the laws of nature and of nature's god entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

This unwritten law of nature insists that every person is entitled to dignity and to some degree of autonomy. Natural law demands fairness. It demands that the strong be gentle to the weak. The English king in 1776 ruled the American colonies with a heavy hand and refused them a voice in their own government. That was a violation of natural law.

The Declaration of Independence might have said, “We Americans are not happy with how England treats us. We are revolting because we want to.” But the link to natural law made the Declaration stronger and more persuasive. It insisted that America’s complaints were based on principles shared by people throughout history. Thomas Jefferson knew about natural law. He had studied the great philosophers, including John Locke, who begins his famous Second Treatise on Civil Government with the state of nature:

To understand political power correctly and derive it from its proper source, we must consider what state all men are naturally in. In this state [of nature] men are perfectly free to order their actions, and dispose of their possessions and themselves, in any way they like, without asking anyone’s permission -- subject only to limits set by the law of nature.

Locke’s state of nature is not the law of nature. It is what exists without any rule or government. In the state of nature, every creature, seeking to survive and depending only on its own capabilities, must constantly fight or flee from fighting. Thomas Hobbes thought life in the state of natural was horrible and, in his 1651 book, Leviathan, Hobbes describes it as “solitary, poor, nasty, brutish, and short.”

No sensible creature wants its life to be short, so the law of nature emerges naturally from the common desire of all living things to survive. The most important (and unique) characteristic of the law of nature is that it is universal. The Catechism of the Catholic Church says the natural law is “present in the heart of each man and established by reason.” (#1956) The Roman philosopher Cicero, writing around 50 years before Christ, also insisted that natural law is inescapable: 

No other law can be substituted for it, no part of it can be taken away, nor can it be abrogated altogether. Neither the people or the senate can absolve us from it. It wants no commentator or interpreter. It is not one thing at Rome, and another thing at Athens: one thing to-day, and another thing to-morrow; but it is a law eternal and immutable for all nations and for all time.”

 The modern Christian writer CS Lewis elaborated on the law of nature in several of his books. And, like Cicero, Lewis insists that natural law is universal and inescapable.

 Some people say the idea of a Law of Nature or decent behavior known to all men is unsound, because different civilizations and different ages have had quite different moralities. But this is not true. There have been differences between their moralities, but these have never amounted to anything like a total difference. If anyone will take the trouble to compare the moral teaching of, say, the ancient Egyptians, Babylonians, Hindus, Chinese, Greeks and Romans, what will really strike them will be how very like they are to each other and to our own.

 Lewis backs up his contention by listing dozens of examples (in The Abolition of Man) of the the law of nature found in cultures and civilizations throughout the world and in every century. Generosity, honesty, decency, loyalty, kindness and other universal virtues are respected everywhere.

• “He who is asked for alms should always give.” (Hindu proverb)

•  “I have not brought misery upon my fellows. I have not made the beginning of every day laborious in the sight of him who worked for me.” (Ancient Egyptian)

• “He whose heart is in the smallest degree set upon goodness will dislike no one.” (Ancient Chinese)

•  “Nature urges that a man should wish human society to exist and should wish to enter it.” (Roman Philosopher Cicero)

•  “When the people have multiplied, what next shall be done for them? The Master said, ‘Enrich them.’ When one has enriched them, what next should be done for them? The Master said, ‘Instruct them.’” (Ancient Chinese Analects)

•  “Speak kindness and show good will.” (Babylonian)

• “They will take care of their kindred and the children of their friends.” (American Indian)

•  “Nothing can ever change the claim of kinship for a right thinking man.” (Anglo Saxon)

•  “Every good man who is right thinking loves and cherishes his own.” (Ancient Greek)

•  “Part of us is claimed by our country, part by our family, and part by our friends.” (Cicero)

These good behaviors are taught by various religions as their own special tenets or by cultures and nations as evidence of their superiority. The people in my home state of Indiana prides themselves for “Hoosier Hospitality.” Residents of various southern states talk about “Southern Hospitality.” In fact, neither Hoosiers nor Southerners are as generous and hospitable as African and Asian people. (And I make that statement after traveling the world!)

With other virtues as with hospitality, people think their ways re special. Few of them recognize that, at their best, they are just following the natural law of all mankind. The more honest and intelligent Christian thinkers recognize that people of all beliefs respect natural law. A person doesn’t need to be religious to be good, because they have a share of Common Grace — a blessing of virtues that all mankind partakes of.

The law of nature never changes, but it does get updated. One recent expressions of the law of nature is found the 1984 rock song, Solidarity, by Little Steven Van Vandt: 

Everybody wants the same thing, don't they? Everybody wants a happy end
They want to see the game on Saturday; They want to be somebody's friend

Everybody wants to work for a living; Everybody wants their children warm
Everybody wants to be forgiven; They want a shelter from the storm

 Look at me, I ain't your enemy
We walk on common ground
We don't need to fight each other
What we need, what we need

Solidarity, Solidarity, Solidarity, Solidarity

Nobody likes to aks for money; Nobody likes to play the clown
Nobody likes to wait in a long line; Nobody likes to be pushed around

 Everybody wants their family protected; They want to express themselves
Everybody wants to live forever; Everybody wants to be somebody else

Look at me I ain't your enemy
Don't believe everything you hear
This is no time to be fighting each other
What we need, what we need is solidarity

The law of nature demands basic decency. It demands that workers deserves fair wages. It insists that every person ought to have a safe and comfortable home, enough to eat, and some opportunity to enjoy beauty, truth and goodness. It claims from every citizen a bit of loyalty and service to the community, while leaving the citizen as free as possible to do as he or she wishes. Those ancient and unvarying goals are still the proper goals for all government and all social action.