Q: Whether Isidore's Division of Human Laws Is Appropriate?

A: On the contrary,
The authority of Isidore (Obj. 1) suffices.

I answer that,
A thing can of itself be divided in respect of something contained in the notion of that thing. Thus a soul either rational or irrational is contained in the notion of animal: and therefore animal is divided properly and of itself in respect of its being rational or irrational; but not in the point of its being white or black, which are entirely beside the notion of animal. Now, in the notion of human law, many things are contained, in respect of any of which human law can be divided properly and of itself. For in the first place it belongs to the notion of human law, to be derived from the law of nature, as explained above (A. 2). In this respect positive law is divided into the
law of nations
and civil law, according to the two ways in which something may be derived from the law of nature, as stated above (A. 2). Because, to the law of nations belong those things which are derived from the law of nature, as conclusions from premises, e.g. just buyings and sellings, and the like, without which men cannot live together, which is a point of the law of nature, since man is by nature a social animal, as is proved in
Polit.
i, 2. But those things which are derived from the law of nature by way of particular determination, belong to the civil law, according as each state decides on what is best for itself.

Secondly, it belongs to the notion of human law, to be ordained to the common good of the state. In this respect human law may be divided according to the different kinds of men who work in a special way for the common good: e.g. priests, by praying to God for the people; princes, by governing the people; soldiers, by fighting for the safety of the people. Wherefore certain special kinds of law are adapted to these men.

Thirdly, it belongs to the notion of human law, to be framed by that one who governs the community of the state, as shown above (Q. 90, A. 3). In this respect, there are various human laws according to the various forms of government. Of these, according to the Philosopher (Polit. iii, 10) one is
monarchy,
i.e. when the state is governed by one; and then we have
Royal Ordinances.
Another form is
aristocracy,
i.e. government by the best men or men of highest rank; and then we have the
Authoritative legal opinions
( Responsa Prudentum
) and
Decrees of the Senate ( Senatus consulta ). Another form is
oligarchy,
i.e. government by a few rich and powerful men; and then we have
Praetorian,
also called Honorary, law. Another form of government is that of the people, which is called
democracy,
and there we have Decrees of the commonalty (
Plebiscita
). There is also tyrannical government, which is altogether corrupt, which, therefore, has no corresponding law. Finally, there is a form of government made up of all these, and which is the best: and in this respect we have law sanctioned by the
Lords and Commons,
as stated by Isidore (Etym. v, 4, seqq.).

Fourthly, it belongs to the notion of human law to direct human actions. In this respect, according to the various matters of which the law treats, there are various kinds of laws, which are sometimes named after their authors: thus we have the
Lex Julia
about adultery, the
Lex Cornelia
concerning assassins, and so on, differentiated in this way, not on account of the authors, but on account of the matters to which they refer.

Reply Obj. 1: The law of nations is indeed, in some way, natural to man, in so far as he is a reasonable being, because it is derived from the natural law by way of a conclusion that is not very remote from its premises. Wherefore men easily agreed thereto. Nevertheless it is distinct from the natural law, especially it is distinct from the natural law which is common to all animals.

The Replies to the other Objections are evident from what has been said.

QUESTION 96

OF THE POWER OF HUMAN LAW (In Six Articles)

We must now consider the power of human law. Under this head there are six points of inquiry:

(1) Whether human law should be framed for the community?

(2) Whether human law should repress all vices?

(3) Whether human law is competent to direct all acts of virtue?

(4) Whether it binds man in conscience?

(5) Whether all men are subject to human law?

(6) Whether those who are under the law may act beside the letter of the law?