Thursday, September 29, 2022

The structure of morality

In physics, we hope for the following unification: there is a small set of simple laws, and all the rest of physics derives logically from these laws and the contingencies of the arrangement of stuff.

In ethics, a similar ideal has often manifested itself. While I have a hope for the ideal being realized in physics, I have come to be more pessimistic about the ideal in ethics. Instead, I think we can have a looser unificatory structure. We can have a multilevel hierarchy of more general laws, and then more specific laws that specify or implement the more general laws.

I suspect the looser structure is what we have in Aquinas’s Natural Law. At the highest level we have the general law that the good is to be pursued and the bad to be avoided. This is then specified into three laws about promoting the goods of existence, species-specific life and reason. These three laws, I think, are then further specified.

There is thus a structure to the moral law, but it is not a deductive structure. The higher level laws make the lower level laws fitting, but do not necessitate them.


William said...

Agreed. In mathematics and you hope physics we have deductive structure. But as we move through chemistry to biology the "laws" become less and less tied to underlying principles. You will not derive mammalian behavior from rules at the level of cellular metabolism such as RNA transcription, for example. Social sciences are even less tied to simpler structures. I suppose ethical rules are in that category.

Should we have expected "Natural Law" to be different from the rules in other social sciences, such as jurisprudence, or is that a false expectation caused by the use of the words "natural" and "law" because of their very different meaning in the context of mathematics or physics?

TreyTable said...

In One Body: An Essay in Christian Sexual Ethics, I recall you arguing for a 'strong ethics of love' such that all moral facts in some sense follow from the fundamental duty to love (or even that they are this duty taking other forms). It's been a while since I read that chapter, but that seems like a tighter unificatory structure than you're posing here, so have your views changed since then or is a strong ethics of love compatible with this looser structure?

SMatthewStolte said...

For physics, is ‘contingencies of arrangements of stuff’ enough? I would think we would also need ‘contingencies of kinds of stuff’. So if there were a particle just like an electron but with a charge sqrt(2) times as big, the laws of physics might still be the same but the behavior of matter would be very different. If so, I’m not sure the moral laws are all that different. You might not be able to derive all the moral laws pertaining to human animals straight from the categorical imperative alone (or whatever other law you take to be fundamental), but you can (can’t you?) derive it from a combination of the categorical imperative and a sufficiently detailed understanding of the nature of the human species. What would be the problem with saying that?

Alexander R Pruss said...


But what makes a particular form of love fitting to a particular lover and beloved's nature may not be encompassed by a simple set of rules.


I think one would need not just the descriptive facts about the human species, but the normative ones. And these would include normative facts about the will, and those will include the moral facts.

SMatthewStolte said...

That answer makes sense, but it requires committing yourself to saying that there are non-normative facts. But see here about Aristotelianism and non-normative facts:

Daryl said...

Pruss, for your response to Matthew -- is the idea that all facts are normative but not all normative facts give us practical reason to pursue or promote them?

Alexander R Pruss said...


I was just thinking that Matthew's "sufficiently detailed understanding of the nature of the human species" would require not just a descriptive but also a normative understanding. For instance, it's important that not only do humans tend to have hearts and lungs, but that they ought to have them.