Cicero, passionately arguing for the grounding of law and justice in nature, points out what happens if one believes that law is instead rooted in the written laws and customs of particular communities at particular times, and individuals are left to obey or disobey as they wish depending on their self-interest. For
then a person will ignore and break the laws when he can, if he thinks it will be to his own advantage. That is why justice is completely non-existent if it is not derived from nature, and if that kind of justice which is established to serve self-interest is wrecked by that same self-interest. And that is why every virtue is abolished if nature is not going to support justice.:”(The Laws I.42, in Cicero: The Republic, The Laws, trans. Niall Rudd [Oxford University Press, 1998], pg. 112.)”:
It should be noted that the reasoning here would apply not just to individual people acting within individual states, but to individual states as well. States can establish laws for pure self-interest as well as any individual can. Positive laws (the existing laws on the books) cannot override the natural law, for this would be to subvert true law and abolish all virtues. Good and bad laws can be distinguished “solely by the criterion of nature.”:”(Ibid., I.43.)”:
But the question may arise as to what the natural law teaches, since one may find men disagreeing over all manner of proposed goods and justices. Cicero considers it axiomatic that a good man cannot fail to love what is intrinsically lovable,:”(Ibid., I.48.)”: and so the reason for men’s disagreements over principles is that pleasure masquerades as goodness and entwines itself with every one of our senses, clouding our minds’ ability to see the things that are naturally good.:”(Ibid., I.47.)”:
How, then, do you know that you’re a good man, and therefore not allowing pleasure to cloud your mind so that you can’t see what is naturally good? The answer is that you must be a philosopher, a man who knows himself, who recognizes the virtues much as all men innately recognize themselves to be creations of the divine,:”(Cicero had earlier said that all men know themselves to be creations of go, even if they disagree about what kind of god, in the same way as every man naturally remembers his place of origin [Ibid., I.25.])”: ceases to serve and gratify the body (thus expunging pleasure “like a kind of discreditable stain,” puts away fear of death, enters into loving fellowship with his fellow man, worships the gods in a pure form of religion, and who has sharpened his moral judgment.
In other words, be a Roman Stoic and you just about can’t help but be a good man and have a life fully in tune with natural reason, natural law, and natural justice. These ideals of Cicero’s had a profound impact upon Christian political thought throughout the Middle Ages, but that is a subject I’ll have to look at another time.