§ 4. On the Obligation of a Law Founded on Presumption

The things which are here said concerning law we will also to be applied to the sentences of a judge.

190. DEFINITION. A law is said TO BE FOUNDED ON PRESUMPTION, when it prudently supposes something on account of which it is made; and it can be defined: A law prescribing, or forbidding, something on account of a certain circumstance, which the legislator supposes to be connected with the thing. But if the supposition of the legislator does not subsist, the law is founded on a false presumption.

DIVISION. A law can be founded on presumption in a twofold way: 1. On a presumption of fact, when namely from probable judgment it supposes fault, negligence, or another fact to exist in particular in reality, for example, a law prescribing obedience to the sentence of a judge supposes it to be just.

2. On a presumption of common danger, which is also called of right, when with certain knowledge it supposes that from such a work, or from such a manner of working, damage, fraud, or grave inconvenience commonly follows; although perhaps it does not intervene in every particular case, for example, a law requiring the proclamations of banns, the solemnities of testaments, the law of the Index as regards books of harmful reading, etc.

191. PRINCIPLES. I. A law founded on a presumption of fact does not of itself oblige in conscience unless the fact exists. The reason is, because, when the truth of the fact is lacking, the law lacks every foundation. Hence the axiom: Presumption yields to truth. We have said of itself; for it can happen that it obliges on account of the public good, for example, to not disturbing order, to averting scandal (I, 100, 150; III, 927).

Hence: 1. "If in judgment it has falsely been proved that your animal inflicted damage, then you are not bound to pay the penalty; and when sentence has been given that you pay, although externally, so that scandal may be avoided, you are bound to pay, nevertheless you can secretly make compensation to yourself."

2. "The same holds for heirs who, because the inventory was neglected, are fined beyond the hereditary goods in paying the debts of the deceased, when in reality the debts exceed the inheritance" (H. Ap., II, 26).

192. II. A law founded on a presumption of right always obliges in conscience, although, in a particular case, no danger underlies it. The reason is, because the presumption of law is not false, and therefore the law does not lack the foundation of binding. For the cause on account of which it was made always subsists, since it supposes that danger is commonly given; which is most true, although in a particular case it does not underlie it. Then, when the end of the law ceases in the particular case, the law does not by this very fact cease, as the common opinion has it (cf. n. 258). Add that the common good forbids that an exception be given, since otherwise evils would not certainly be averted, nor especially would the danger of hallucination on the part of subjects be excluded (I, 199; ed. G., I, p. 178). Therefore in these laws, judgment in the forum of heaven, that is, of conscience, ought to be the same as in the forum of the court (Lugo, de Just., disp. 13, n. 62).

Hence, you are bound to abstain from the reading of prohibited books, even if no danger of perversion threatens you from reading of that kind.¹ Likewise, you are bound to pay the fine to which you have been condemned on account of damage which your beast truly inflicted, even though the damage was inflicted without your fault. For the end of the law is not only to punish fault, but also to render men more cautious.

Before sentence, however, you are not bound, if the law is merely penal; or if you doubt whether it is founded on a presumption of right or of fact; whether it is invalidating by the fact itself or through a judge, etc. The reason is clear from what was said in the preceding paragraph.