Thomas offers two descriptions of Natural Law – as summarized by the authors:
What is natural law? One description of it is: the peculiarly human participation in the eternal law, in providence. All creatures are ordered to an end, have natures whose fulfillment is what it is because of those natures.
This is true not only of humans, but of all things. However, other things are ordered to ends of which they are not conscious. Only humans are aware of the good and freely direct themselves toward it – more precisely, one is free to direct himself, or not, toward his true end.
We can very much see Aristotle here, as everything has an end or a purpose, inherent in it due to its material and form – its nature, if you will.
A second description of natural law is: the first principles or starting points of practical reasoning.
What is this starting point? Our first conception is of being: we call “mama” or “dada” or “hot.” It “is a specification or an instance of that which is, being.” So too regarding first judgment: “You took my mitt.” “No, I did not.” While they certainly disagree on this point, they both agree that one did not both take the mitt and not take the mitt at the same time.
It is on an analogy with these starting points of thinking as such that Thomas develops what he means by natural law. In the practical order there is a first concept analogous to being in the theoretical order and it is the good. The good means what is sought as fulfilling of the seeker. The first practical judgment is: the good should be done and pursued and evil avoided. Any other practical judgment is a specification of this one and thus includes it.
So there is being and there is judgment, and these are the starting points of practical reasoning. These are aimed at the good – the ends to which humans are ordered. And the manifestation of this good is Jesus.
These will be fashioned with reference to constituents of our complete good—existence, food, drink, sex and family, society, desire to know. We have natural inclinations to such goods. Natural law precepts concerning them refer the objects of natural inclinations to our overall or integral good, which they specify.
Does this suggest that there is only one possible set of means by which to achieve the ends for which humans are aimed? Not at all.
…there are innumerable ways in which human beings lead their lives in keeping with the ultimate end. … So the lives of human beings will show a great deal of variation in the ways they pursue the human end in accord with these general principles.
We have liberty in the means, but nature (if you will) gives us the ends.
The authors offer a comment on Thomas, and following Aristotle, in claiming that man is a social or political animal. “[H]e does not mean that each of us has a tendency to enter into social contracts or the like.”
The natural in this sense is what is not chosen, but given, and what is given about human life is that we are in the first place born into the community of the family, are dependent on it for years in order to survive, and that we flourish as human beings within various larger social and political communities.
We don’t enter into social contracts; we are born into a social condition and we are dependent on the stability of this social condition for our survival. I am reminded of something from Murray Rothbard:
Contemporary libertarians often assume, mistakenly, that individuals are bound to each other only by the nexus of market exchange. They forget that everyone is necessarily born into a family, a language, and a culture.
It seems to me that any political theory – certainly one focused on liberty – should take this reality and necessity into account.
The moral consists in behaving well in these given settings.
The implications for liberty are significant, but it is too early in this study to dive into this – I still have other sources through which I want to understand Aquinas, let alone dive into the implications.
However, what strikes me is the following: say it’s true – Plato’s Form of the Good; this Form found in being as per Aristotle; Jesus is the perfect example made manifest for humans; we aim at good as outlined by Aquinas; from all of this we can derive Natural Law.
So say this is so. It is all in us – just as these philosophers suggest. It is natural for us to want to act on such a basis and in such a manner. It makes one wonder: if this is how we are intended to act, can you imagine the tension in us and in society when we purposely act otherwise – when we set our own ends, in defiance of our nature?
Sure, it might sound like liberty. But this seems quite superficial, and a superficial definition of liberty. It is also unsustainable – what being can constantly and continuously go against its natural ends or purposes and survive as the being it was intended to be?
I am reminded here of C.S. Lewis, from The Abolition of Man:
They are not men at all. Stepping outside the Tao, they have stepped into the void. Nor are their subjects necessarily unhappy men. They are not men at all: they are artefacts. Man’s final conquest has proved to be the abolition of Man.
Many libertarians base their libertarianism on selective natural law; it is not a natural law grounded in Aristotle and Thomas; it is not a natural law that respects the entire man, thus ensuring his abolition. I don’t believe liberty will be found down this road.
Thomas's teaching came under attack, largely by Franciscans, immediately after his death.
This would begin to change in 1879, when Pope Leo XIII called for the revival of the study of Thomas. This was not for the purposes of choosing one school over the other; he was looking for a defense against the modern thought that came into being since Descartes. The response to Leo’s call was global.
This came to an end with Vatican II in the early-to-mid-1960s. The timing was fortuitous – just at the same time that cultural Marxism and deconstruction into nothingness took root.
Now with the vogue of the notion that modernity has failed and the Enlightenment Project come a cropper, many, Catholics and non-Catholics alike, are turning to Thomas as a spur or foil for their thinking.