Aquinas on the natural law, or how to avoid centuries of bloodshed

A redated post

These are my class notes on Aquinas and the natural law. But notice something important. If Christians had realized from the 13th Century on that governments are set up to secure human earthly happiness, how much blood on the hands of Christians could have been avoided?

The Natural Law
How right and wrong are based on reason
I. Human nature and the natural law
We can reflect upon human nature and find those things that will help us actualize our potentialities. This is what Aquinas calls natural law.
Human nature is the same from culture to culture and from century to century. So we can discover the natural law by reason.

II. Using reason to discover the law
How do we discover which objects, circumstances, and ends are good?
The good is determined by reason, what is in accordance with the natural law.
We can derive moral principles by reflecting on what is in accord with nature and our natural inclinations.
Since we have a natural inclination to preserve ourselves, suicide is against the natural law.
It is natural to care for our offspring, so we must educate our young to see that they reach their potential.
Since we are higher than the beasts, we must actualize out potential by pursuing the truth, including the knowledge of God.

III. Why don’t we all agree?
We are blinded by passion, bad habits, and ignorance.
Do we know these things in our consciences? Conscience is not a source of knowledge itself, but is that rational activity of apply moral knowledge to particular cases.
Conscience is fallible, but the best we can do is follow our informed conscience to the best of our abilities.

IV. Aquinas’s Four Laws
Eternal Law
Natural law
Divine law
Human law

V. The Eternal Law
The eternal law is the law by which God governs the universe.
Everything in natural follows the eternal law blindly, but humans have the capacity to obey it or disobey it.

VI. Natural law
Discussed earlier, the law available to reason that governs human moral behavior and is aimed at human happiness on earth. The virtues enjoined by natural law are temperance, courage justice, and wisdom.

VII. Divine Law
The divine law is given to us by revelation, and concerns how to achieve eternal happiness, in other words, how to be saved.
The virtues enjoined by this law are faith, hope, and love, the three holy virtues.
These can only be obtained through the grace of God.

VIII. Human law
Human law is instituted by governments.
If the law is legitimate, it must be rooted in the natural law. To obey such laws is to obey God.
Any human law that violates natural law is not a law at all.

IX. Aquinas and Dr. King
This raises a question of illegitimate laws, such as racially discriminatory laws (Jim Crow laws). Religious leaders in the South had written Dr. King a letter saying that while they approved of his coming to Alabama to work for civil rights, they asked that he obey the laws of the state while he was there. King didn’t follow their advice, and wrote the famous Letter from the Birmingham Jail explaining why. Aquinas says in some cass it is the lesser evil to obey a bad law to keep the peace, but in other cases civil disobedience in the name of a higher law may be necessary.

X. Aquinas an Human Laws
Some laws enforce the natural law  and should be uniform from one society to another (laws against murder and theft, for example).
Other laws set out details left open by natural law for the sake of uniformity in a society. It doesn’t matter if you drive on the right or the left, so long as everyone drives on the same side.
Other laws have to be reached on the basis of situational judgment. How old should a person have to be to drive a car. 16 seems to low of an age in urban Phoenix, but too high for rural Kansas.

XI. The extent of the law
Human law should not attempt to render illegal all kinds of immoral behavior. It should only be concerned with major evils that harm others and undermine and ordered society.

Political legislation should concern matter of justice, and should stay out of issues that concern spiritual matters or private morality. This is because human laws must be grounded in the natural law (aimed at human earthly happiness and not at salvation, and discoverable by reason) and not divine law (known by revelation and aimed at human happiness).

This represents the foundation of the separation of church and state, and on these matters the Catholic Church deviated from Aquinas’s teaching when they used the power of the government to enforce Catholic belief. After the Inquisition and the Wars of Religion (which left 1/3 of the population of Europe dead), we can see that Aquinas had it right.