This post stems from my difficulties in teaching the natural law to undergraduate and graduate students. One difficulty is the lack of any decent accompanying text (I think mine is an exception, but I’m not writing this to promote my work). Most texts argue along the following lines:
natural law is not about human nature as it is, but about human nature at its best . . . . . . [60,000 words] . . . . . . And so you see that abortion and homosexuality are against natural law.
It is as if the point of natural law is to justify the author’s convictions. An example is Morality and the Human Goods: An Introduction to Natural Law Ethics, by Alfonso Gómez-Lobo, but there are many others.
I’m not sure how to best approach the natural law, but I’m pretty sure it’s best not to use it to justify an agenda.