At the TAC colloquium on the common good I attended this June, a disputed question came up regarding St. Thomas's definition of law in question 90 of the Summa:
Law is an ordinance of reason for the common good, made by him who has care of the community, and promulgated
Two scholars put forward an interpretation of that definition I had never heard of, but seemed plausible: that the 4 parts of the definition correspond to the 4 Causes. Thus:
Formal cause= ordinance of reason
Final cause= for the common good
Efficient cause= he who has care for the community
Material cause= modes of promulgation
When I asked the scholars where this interpretation came from, they replied it was not explicitly in the text of St. Thomas, but an interpretation put forward in the excellent “Commentary in the Treatise on Law” by University of Texas professor JD Budziszewski. In his book he says:
St. Thomas is proposing to give an account of the four causes… of the law. His first point of inquiry addresses its form, his second its end, his third its power, and his fourth its matter. In the strict sense of the term, the essence of law is expressed by its formal cause alone, as discussed in Article 1. But St. Thomas brings in its other three causes in Articles 2-4, because the are essentially connected with its formal cause. (12)
Do you buy Budziszewski’s interpretation?
It seems to me: maybe. But does St. Thomas or Aristotle define anything else in terms of the 4 Causes? I think even based on what Budziszewski writes one could argue the definition is all about the formal cause. Arisotelian philosophical definitions usually lay out the genus and specific difference of a thing. Later philosophy demands that a definition lay out the necessary and sufficient conditions of a thing.
Just what was Aquinas up to in defining the essence of law as he did?
Promulgation as the material cause seems like the one which is more of a stretch than the others. Is the posting a law in a town square for people to read really a material cause of something?
Dear Chris, thanks for bringing this up; this has long (I mean "for decades") been an issue for me. To start with your last question first: in Q. 55, the definition of the essence of virtue, Thomas follows the track you lay out: he starts with genus-species thinking in the first three Articles, then in the fourth, he brings in the four causes. I take that to be an exemplary case of essential, that is, definitional, thinking in Thomas. When I encounter a Question with four articles, I assume/expect that Thomas will be attempting to define the subject, and do so, eventually, in terms of the four causes.
It doesn't quite work, however, in connection with the essence of law in Q. 90. I only see three of the four causes, and I see the efficient cause covered twice. I explain: I think we all agree that article one, an ordinance of reason, is the formal cause; and article two, on the common good, is certainly the final cause. That just leaves two causes to cover: efficient and material. But here's the rub. Promulgation certainly seems to be (an) efficient cause. But can "he who has care of the community" be the material cause? No. (I'll get to what I think the material cause is in a second.) It seems to me that three and four go together and together designate the efficient cause as a power (or office) and an act. That leaves the material cause. Well, what matter does law form? Human actions, insofar as they bear upon the common good. One can tidy up this last formulation, but it seems clear to me that the matter that law forms is human beings as agents, members of a perfect community, and their external actions, insofar as they bear upon the community's good life. As we learn later in the Treatise on Law, Thomas is very wary of legislating internal actions, as well as all of human morality, whether vicious or virtuous. He's the first Whig (I say to tweak any number of people who appeal to him for their "common good" agendas.)