Summa summae S. Thomae, Tomus II

I say 1°: The legislator, his successor or superior can abrogate a law, and a fortiori derogate from it; because it belongs to the same power to destroy and to build up.

[Benedict XIV, de Synodo dicc., lib. XIII, c. 5, n. 9, proposes this question, namely: « Whether it be within the competence of the bishop either to delete entirely the synodal constitutions made by himself, or to exempt anyone from them for a just cause, when the same have been confirmed by the authority of the supreme Pontiff? » Having related various opinions, he proceeds, n. 11: « The opinion of Fagnanus seems to be preferred to the others, in cap. Si quis, from n. 11 up to 24, de Confirmatione utili vel inutili, where he teaches that a distinction must be made between confirmation which they call in forma communi and confirmation in forma specifica. It is said to take place in forma specifica in the case of one to which is premised the examination of the cause and each statute is diligently weighed, and then, no condition being added, it is confirmed with apostolic authority, with the clause: motu proprio atque ex certa scientia. Statutes which are not examined singly, nor approved by the Pontiff motu proprio and ex certa scientia, and to which the strength of apostolic authority is not added absolutely but only conditionally, namely if they were made justly, canonically or providently, and provided that they do not run counter to the sacred canons, the Council of Trent, the decrees and apostolic constitutions, are said to be confirmed in forma communi; that latter condition, as the same Fagnanus testifies, n. 18, is wont today to be expressed and set before all confirmations of statutes in forma communi. But now, Fagnanus proceeds, once a statute has been confirmed in forma specifica, since it has put on the nature of a pontifical law, it is not lawful for any inferior to derogate from it. A statute however confirmed in forma communi remains within the competence of those standing to delete, and to withdraw anyone from its obligation for a just cause. For such confirmation bestows on them nothing of law or efficacy which they previously lacked. »]

I say 2°: A general law is considered revoked by a contrary general law. But a particular law, such as are the special customs, statutes and privileges of places, even if there is placed in the general law this general derogatory clause: « Notwithstanding any custom whatsoever, » etc., is not considered revoked unless special mention is made of it, or unless it is otherwise evident that this is the mind of the legislator. So Boniface VIII, cap. Licet, de constit. in 6°,

[Where he says: « Although the Roman Pontiff, who is considered to have all laws in the shrine of his heart, is known to revoke the prior constitution by enacting a later one, although he makes no mention of it; yet since the customs and statutes of special places and individual persons, being matters of fact and consisting in fact, he can probably be ignorant of them, he is not understood by a constitution newly issued by himself to derogate anything from them, so long as they are reasonable, unless provision is expressly made in it. »]

I say 3°: The adequate end of the law simply and absolutely ceasing, and in common, the law ceases; because 1° that is not a law which is not useful to the common good. Therefore, the reason for which it was useful ceasing, it ceases. 2° Because, the reason for which the legislator enacted the law ceasing altogether, he is considered no longer to will it to oblige.

I said: « The adequate end ceasing, and in common; » because, if a law is enacted concerning some work because it is apt to conduce and for the most part does conduce to the common good, although in some particular case, per accidens, de facto it does not conduce, nevertheless the law does not therefore cease, because the end of the law does not cease adequately. E. g., the law prohibits the reading of condemned books, because of the danger of perversion: although you are so disposed that you do not fear perversion in yourself, yet since thence it is apt to follow and for the most part follows, the end of the law remains, nor are you exempted from it.

[You will ask whether the obligation of the law ceases in the particular case if its end then ceases contrarily, that is, if the observance of the law redounds against its end.

I answer. Affirmatively. The reason is, because what is instituted for the common good ought not to fight against it; which would happen if the law were made harmful to the common good, or even to the good of some private person, whose evil redounds against it: as if the law of fasting, which binds when other foods are lacking, or binds anyone because of ill health, were too burdensome; for it concerns the interest of the common good that private persons be kept unharmed.]