This is your resident Thomist bringing you a minute from the Bellowing Ox.
What is the natural law? Thomas highlights 4 precepts following Cicero. One of those precepts is self-preservation.
When you got up this morning, did you eat breakfast? Ever heard a bump in the night, and with heart pounding, prepared to hide or defend yourself? If you have, you have followed the 2nd precept of our natures.
Politicians and those with a political agenda often criticize the natural law because many who are religious hold to it. They treat it as mere faith, when in reality it is grounded in experience and human behavior. Usually, those who deny it do so because they want to protect abortion or so called “gay marriage.” The label is applied so as not to have to deal with the impact of the reality.
So how does self-preservation threaten abortion or gay marriage? If we by nature seek to preserve ourselves, it suggests an underlying goodness to our natures, which threatens the dehumanizing tendencies of abortion. Similarly, gender confused or homosexuals tend to have higher suicide ideation and rates, higher rates of drug abuse, higher depression rates, and so on. Self-preservation suggests these things are a problem. So rather than deal with the natural law as something grounded in reality, it is labeled and shunned as fideism.
We can learn a lot from the natural law, first and foremost, we can learn virtue. Virtue is what makes us happy. Maybe we all ought to get out our ear horns and listen to the Bellowing Ox.