Moral Theology / A Complete Course Based on St. Thomas Aquinas and the Best Modern Authorities

by John A. McHugh; Charles J. Callan

Art. 3: A CERTAIN CONSCIENCE

(_Summa Theologica_, I-II, q. 57, a. 5; II-II, q. 47, a. 9.)

640. As was said above, only that conscience is a safe guide which is not only good—that is, in agreement, as far as one’s efforts can secure this, with the external law—but also certain. A certain conscience is one which, without any prudent fear of erring, judges that a particular act is obligatory or unlawful, and hence here and now to be done or omitted.

641. Necessity of Certitude.—We must be sure we are right before we act; otherwise, we expose ourselves to the danger of sinning, and therefore commit sin (see 582). Hence, it is necessary to act with a certain conscience, and unlawful to act with an uncertain conscience. “If the trumpet give an uncertain sound, who shall prepare himself to the battle?” (I Cor., xiv. 8) may be accommodated to conscience. In Rom., xiv. 22, 23, the Apostle declares that he who acts with conviction is blessed, whereas he who acts in uncertainty is condemned. Examples: Sempronia doubts whether it is sinful to sew on Sunday; she is not sure, but has grave suspicions that sewing is servile work; if she goes ahead, she will be guilty of violating the law, as being willing to take the risk, and therefore the responsibility. Titus offers another a drink, being uncertain whether it has poison in it or not; he is guilty of sin, since he has no right to expose himself to sin and his neighbor to the danger of death.

642. Those persons who act with a doubtful conscience, and later discover that what they feared might be wrong was not wrong, or not so bad as they suspected, must bear in mind: (a) that their past conduct is not to be judged by their newly acquired knowledge, for that conduct must be judged by the knowledge had at the time. Example: Sempronia does some work on Sunday, doubting whether she is committing a grave or a slight sin. Later she discovers that it was really only a venial sin, and she congratulates herself that she did not sin seriously. Her judgment is wrong, because she did not know at the time of the work that it was not a grave sin; (b) that they must guide themselves in future acts by their newly acquired knowledge.

643. Kinds of Certitude.—Judgments may be certain in a greater or less degree.

(a) They are metaphysically certain, when error is absolutely impossible, the opposite of what is held by the mind being a contradiction in terms which omnipotence itself could not make true. Example: The judgments that the same, identical act cannot be both good and bad, that good is to be done and evil to be avoided, that God is to be honored, are metaphysically certain, since they result immediately from the very concepts of being, of goodness, and of God.

(b) Judgments are physically certain, when error is impossible according to the laws of nature, the opposite of what is held by the mind being unrealizable except through intervention of another cause. Example: The judgments that he who takes poison will destroy life, that he who applies fire to a house will destroy property, are physically certain. because natural agencies, like poison and fire, act infallibly when applied to suitable matters and under suitable conditions and left to their course, unless they are overruled by superior power.

(c) Judgments are morally certain, when error is impossible according to what is customary among mankind, the opposite of what is held by the mind being so unlikely that it would be imprudent to be moved by it. Examples: One is morally certain that what a reputedly truthful and competent person relates to one is true. A person is morally certain that a conclusion he has drawn about his duty in a particular instance is correct, if he believes that he has overlooked no means of reaching the truth. Testimony and inference, since they come from free and fallible agencies, may lead into error; but, when they appear to have the requisite qualities indicative of truth, they are for the most part reliable and in practical life have to be considered as such.

644. As to the certainty that is required in the judgment of conscience, the following points must be noted:

(a) Metaphysical certainty is not required, since conscience does not deal with primary propositions, but with deductions about particular acts. The first moral principles, which are the object of synderesis, and at least some of the general conclusions, which are the object of moral science, are metaphysically certain (see above 145, 300), as they are based on necessary relations; but the particular conclusions, which are the object of conscience, are concerned with the contingent and the individual.

(b) Physical certainty is not required for the judgment of conscience, since conscience is not concerned with the activities of natural agents, but with the activities of moral agents that act with freedom and responsibility.

(c) Moral certitude, therefore, is sufficient for the conclusions drawn by conscience. That a higher kind of certitude is not necessary should not surprise us, for it would be unreasonable to expect that the same degree of assent be given to judgments that are concerned with particular and contingent cases as to those that are concerned with universal and necessary principles.

645. Moral certitude is of two kinds: (a) certitude in the strict sense, which excludes not only the fear of error, but every doubt, prudent and imprudent, great and small, Example: Titus thinks of a way in which he could easily make money dishonestly; but his conscience sees that the thing is manifestly wrong and decides without the slightest fear or doubt that it must not be done; (b) certitude in the wide sense, which excludes all fear of error and every serious or prudent doubt, but not one or other slight and imprudent doubt. Example: Caius was baptized by an excellent priest, but the date was omitted in the register. The doubt occurs to Caius that perhaps something essential was also omitted, and that it may be his duty to seek another Baptism. His doubt is unreasonable.

646. Moral certitude in the wide sense is sufficient for a safe conscience, even in matters of great importance, since it is frequently the only kind of certitude one can have, and he who would strive to be free from every slight and baseless suspicion would be soon involved in a maze of scruples and perplexities. Example: If the Caius above referred to were to yield to his doubt and be rebaptized, a similar doubt about the second Baptism might easily arise in his mind, and he would be no more contented than before.

647. From the point of view of its object, certitude is twofold. (a) Speculative certitude refers to a judgment considered as a general law, abstraction being made from particular circumstances. Example: It is speculatively certain that farm work on a holyday is a forbidden kind of work, and that clerics are obliged to say the Divine Office. (b) Practical certitude refers to a judgment which is an application of a general law to a particular case, consideration being given to all the pertinent circumstances. Example: It is practically certain that Titus may make hay on a holyday, if otherwise he will suffer great loss; and that a cleric is excused from the Divine Office, if his physician has warned him that he is physically or mentally unable to perform it.

648. Speculative certainty is not sufficient for conscience, but practical certitude is required, since conscience refers not to abstract laws but to concrete cases—not to what is right if only the object of the act is considered, but to what is right when one considers the object, the motive, and all the circumstances here and now present.

649. From the point of view of the arguments on which it is based, certitude is of two kinds. (a) Demonstrative certitude is the assent that rests on a conclusion logically drawn from certainly true premises. Example: Caius argues that he is obliged to go to Mass on Sunday, because the law is certain, and it is also certain that the law applies to him. (b) Probable certitude, which is the assent that rests on a conclusion, whose premises, though not certain, seem to be true, and against which there is no counter conclusion, or none that cannot be readily answered (see 703). Example: Caius is pretty sure that he is seriously ill, because he perceives a number of alarming symptoms; the possibility that these may be due to imagination is excluded by the fact that they are new and sudden. Caius, therefore, concludes that he may hold himself excused from attendance at Mass.

650. Probable certitude is sufficient for conscience, for in moral matters it is impossible to have at all times reasons that amount to a demonstration, and hence a person acts prudently in following a decision that is solidly probable and unopposed by any contrary serious probability. What is called “probable certitude” here is very different from probable opinion, about which there will be question below (662 sqq.)

651. From the point of view of the manner in which it is obtained, certitude is again twofold. (a) Direct certitude is that which is obtained from principles that are intrinsic to the case by applying to the matter the law concerning it. Examples: A judge who decides according to the evidence and proofs given in court that an accused is guilty, and a son who concludes from the Fourth Commandment that he is bound to help his parents in necessity, have direct certainty in their judgments, because they argued from principles that deal with the question before them. (b) Indirect certitude is that which is obtained from principles that are extrinsic to the case by applying to the matter in hand reflex principles (i.e., rules that direct how one should act in doubt) or the principle of authority (i.e., the argument drawn from the opinion of those who are acknowledged as competent to decide). Examples; If a judge is not able to form a certain judgment from intrinsic reasons concerning an accused, because strong arguments have been given both for guilt and for innocence, he has recourse to principles that have reference to his own state of doubt, and which declare that he must acquit when he is not certain of guilt. If a man is not able to decide whether the Fourth Commandment obliges him to keep his grandparents or mother-in-law in his home, when they upset his family and are able to take care of themselves, he can have recourse to the external principle of authority by consulting his confessor.

652. Direct certitude is not necessary for the judgment of conscience, for often, as in the cases just mentioned, it is not possible. Moreover, indirect certitude suffices to give one who is in doubt such practical assurance that one’s fears become unimportant and one is able to act prudently in spite of them.

(a) The principle of authority—that “in doubt we can safely follow the advice of those who are experts and truthful”—is reliable, as both the conditions required for authority (viz., knowledge and truthfulness) and also daily experience show.

(b) Reflex principles likewise, although they do not prove what is deduced from them, are well founded, and point so clearly the side to be taken when judgment is suspended between alternatives that they enable one to act with all the certitude that prudence demands. Example: The principle that “in doubt decision should be given in favor of the accused,” is based on the fact that a man’s right to his life and liberty is so certain that he does not forfeit that right unless it is proved convincingly that he is guilty.

653. Examples of uncertain and certain consciences are the following:

(a) Uncertain conscience: It is lawful to make a just contract (major premise certain); but this contract is just (minor premise a matter of doubt or opinion); therefore, this contract is lawful (conclusion a matter of doubt or opinion).

(b) Conscience directly certain: It is lawful to make a just contract (certain); but this contract is just (certain); therefore, I may make this contract (certain).

(c) Conscience indirectly certain: It is lawful to follow competent advice or a moral system approved by the Church (certain); but a competent spiritual adviser or an approved system of Moral Theology holds that this kind of contract is lawful (certain); therefore, it is lawful for me to make this contract (certain).

654. An Uncertain Conscience.—Uncertainty of conscience can be understood in two senses.

(a) Conscience is uncertain in a more strict sense, if the verdict of the moral judgment on a question of lawfulness or unlawfulness is that no decision can be given either way, either because there are no reasons of importance on either side (negative doubt), or because the opposing reasons balance so perfectly that it is impossible to choose between them (positive doubt). Examples: Titus, wishing to do some drawing on Sundays, asks himself whether drawing is servile work. Not knowing the definition of “servile,” he can only reply to his doubt that he has no reasons either for affirmation or for negation. Caius reads moral authors on the same question, and the pros and cons seem to him so equally strong that he cannot pronounce for either side.

(b) Conscience is uncertain in a less strict sense, if the verdict of the moral judgment on a question of lawfulness or unlawfulness is that the mind inclines to one side more than the other, but cannot decide in its favor (suspicion), or that it decides for one side, while perceiving that the arguments for the contrary are not to be despised (opinion). Example: Titus decides to spend a good part of Sunday taking photographs. Caius argues that this is unlawful; Sempronius, that it is lawful. Titus thinks the arguments of both are strong, but is better pleased with those of Sempronius. If he feels he cannot act on either opinion, his state of mind is what we called suspicion; if he feels that the opinion of Sempronius has prevailed, his state of mind is one of opinion.

655. From what was said above concerning the certitude requisite for conscience (see 641 sqq.), it follows that: (a) when the state of mind is positive or negative doubt, one is not allowed to act; for a person who is ignorant of what he should do, or who is fluctuating between opposites, runs the risk of sin and its consequences, if he acts blindly; (b) when the state of mind is suspicion, one is not allowed to act, for conscience must be more than conjecture or inclination; (e) when the state of mind is opinion, one is or is not allowed to act, according as the opinion has or has not the qualities required for certitude that is moral and practical (as explained above in 643 sqq.).

656. Doubt and Suspicion.—The following are the duties of a person whose state of mind about his obligation is one of doubt or suspicion:

(a) If he has no time to resolve his hesitation but must decide at once, he should follow the rules given for a perplexed conscience (see above, 611 sqq.). Example; Sempronius is ordered by his father to go on an errand; by his mother, to remain at home. He does not know whom he should obey, but argues that there can be no harm in performing the errand, since he feels that he is forced anyway. Sempronius’ impromptu decision proceeds from a sense of moral responsibility; it is good, and as certain as he is able to make it.

(b) If a person has time to resolve his hesitation, he should not trust to common sense, but should consult moral theology, if he is competent to understand and apply it, or should have recourse to his confessor, if he is not a theologian. The attention given to his problem should be proportionate to the gravity of the duty in question, its importance for third parties, etc. (see below, 667 Sqq.). Example: If a layman is uncertain whether a practice he follows in his business is dishonest, he should consult a priest; if the priest is uncertain, he should refer to his theology and study the matter until he is able to give a well-founded, morally certain judgment.

657. Reflex principles by the aid of which a negative doubt may be solved, when the question is about the existence or non-existence of some fact connected with obligation, are the following:

(a) If the fact at issue is one about which presumption may be had from general or personal experience, the doubt may be settled by the principle: “In uncertainty decide according to what usually happens.” Examples: Titus is uncertain whether his boy of seven years has the use of reason and is bound to go to Mass. As a rule, children attain discretion at the age of seven; and hence Titus should take his boy to Mass. Fr. Caius is uncertain whether he has said Terce. His experience is that such uncertainties on his part have always been baseless in the past; hence, he may consider that he has said Terce as usual.

(b) If the fact at issue is one about which no presumption is afforded, either from general or personal experience, recourse may be had to the principle: “A fact should not be taken for granted, but must be proved.” Examples: Sempronia doubts whether her practice of saying the Rosary daily was the result of a vow; but, as there is no proof or circumstantial evidence of a vow, it may be held that her practice originated in a resolution. Caius, a stranger, claims that Titus owes him for an unpaid debt of his father. Titus knows nothing of the alleged debt, and the only substantiation for its existence is the word of the stranger. Titus is not obliged to pay.

658. Presumption of a fact is of three kinds according to Weight:

(a) Violent presumption is based on indications so significant or numerous that it leaves only slight room for evasion. This kind of presumption suffices, but is not essential in solving doubts. Example: Caius has no direct proof or disproof that he paid Titus in a certain business transaction, because all the papers have been lost. But he remembers distinctly that he drew the money and went personally to the office of Titus on the day payment was to be made, and that the latter, up to the time of his death several months later, always acted as if full settlement had been made.

(b) Strong presumption is based on circumstances or signs so moving that they permit one to infer a fact as being their natural or usual accompaniment or result. This kind of presumption suffices in solving the doubts we are considering. Example: If Caius, spoken of above, has no individual recollection of any circumstances bearing on the payment of his debt to Titus, but knows that it was his invariable custom to pay all his debts promptly, the presumption that he paid this debt is strong.

(c) Light presumption occurs when the reasons are so slight, that they hardly ever suffice to permit us to infer a given fact from them. Example: If we suppose that Caius was dilatory in paying debts, and that he has no better indication of payment having been made than the fact that Titus gave him a cigar about the time of their business transaction, there is little presumption that the debt was paid.

659. Reflex principles that may be used to settle negative doubts about the quality of an act performed are the following:

(a) If there is an individual presumption, the quality of the act may be inferred from what usually happens. Example: Sempronius cannot remember whether a certain good work he undertook was prompted by zeal or ambition. But, as he usually tried to keep his motives pure, it may be concluded that the work in question proceeded from a right intention.

(b) If there is no individual presumption, the quality of an act may be settled from general presumptions or principles. When the act was according to law, and the doubt concerns its validity or sufficiency, one may take it that all was rightly done; for it usually happens that he who complies with the substance, also complies with what is accessory. Moreover, the welfare of the public and of individuals require that an act done outwardly according to law should be deemed as rightly performed unless the contrary can be proved. Hence the rules: “In doubt decide for the validity of what was done”; “What has been done is presumed to have been rightly done.” Examples: Caia cannot remember whether she really consented when she married Titus. Sempronius cannot remember whether he had sufficient attention in hearing Mass on Sunday. The presumptions are that Caia married validly and that Sempronius heard Mass properly, if they acted in good faith.

660. Reflex principles that may be used to settle negative and invincible doubts concerning law or obligation are the following:

(a) If no serious reasons can be found to prove or disprove the existence of a law, or its gravity or application to a present case, use may be made of the principle: “Invincible ignorance of the law excuses from sin.” Example: Titus on an ember day consults all the sources of information he has to discover whether it is a fast day; but all he can learn is that some vigils are fast days, others are not.

(b) If no serious reasons can be found to prove or disprove that a law bears a certain meaning, recourse may be had to such principles as the following: “A law obliges only in so far as it is knowable”; “The interpretation may be made against the legislator who could have spoken more clearly”; “Things burdensome to the subjects of the law should be construed narrowly; things favorable, broadly.” Example: Caius, who supervises workingmen, has no notion regarding the meaning of the word “workingman” as used in an indult on fasting—viz., whether it applies to supervisors of work or exclusively to laborers.

(c) If no serious reasons can be found to prove or directly disprove that a certain law has ceased or been abrogated, the principle to be followed is: “In doubt decide for that which has the presumption.” In this case the presumption is for the continuance of the law, since it was certainly made, and there is no probability for its non-continuance. Example: Sempronius learns that certain mitigations have been made in the law of fasting, and wonders whether the same is true as regards the law of abstinence; but he has no reason to think that any change has been made on this latter point.

661. In the above cases negative doubt was solved generally in favor of non-obligation as against obligation. But there are two cases in which negative doubt must be settled in favor of obligation, according to the rule: “In doubt follow that which is safer.” The two cases are:

(a) Negative doubt must be settled in favor of obligation, when the doubt is about a matter of such importance that it does not permit the taking of risks in its performance, as when there is question of laws that safeguard the supreme rights of man, or of laws that prescribe the essentials to be used in the administration of the Sacraments. Example: Sempronius adopts a newly-born infant abandoned at his door. As there is nothing to indicate whether the baby has been baptized or not, Sempronius takes the safer course and has it baptized.

(b) Negative doubt must be settled in favor of obligation when it persists because no reflex principle is found, or none that seems to be suitable for the case. Example: Titus wavers between uncertainties about the existence of a law; he can discover no reasons pro or con, and he knows no principle or presumption to guide himself by in his difficulty. He does not know or even think that he may act as if the law were non-existent, and hence he must inquire further, or else act as if the law did exist.

662. Opinion.—The duty of one whose state of mind is opinion is as follows:

(a) If he is able to remove every objection against his judgment or to make unimportant such objection or objections as remain, his opinion has become moral certainty (see above, 644 Sqq.), and he may follow it as a safe guide. Example: Caius promises to marry Sempronia, but his parents forbid the marriage. Caius opines that he should keep his promise, but to be sure he consults his pastor. The latter shows him that the opposition to his marriage is unreasonable, and thus sets at rest the difficulties of Caius.

(b) If a person is not able to remove one or more important objections against his judgment, his opinion has not become moral certitude, and he may not follow it as a safe guide. Example: If Caius’ pastor holds that the parents are right and Caius wrong in the question of marriage with Scmpronia, so that Caius, while still thinking he should keep his promise, has serious fears that it would be a wrong step, the young man should not follow his own view.

663. Those who act when their state of mind is doubt, suspicion, or uncertain opinion are: (a) guilty of sin, for they do not act in good faith (Rom, xiv. 22, 23), and they are imprudent and lovers of danger (Ecclus., iii. 27); (b) guilty of the species and gravity of sin which they fear may be in their act; for they interpretatively wish that to which they expose themselves. Example: If Titus takes an oath, fearing that his act is perjury, he is guilty of perjury before God, even though what he says is true.

664. Fears or objections against an opinion are unimportant as follows: (a) if they have only a slight probability (e.g., Titus opines that he is not obliged to say the second lessons, because he knows that he began them, and therefore must have said them; but he fears he may be obliged to say them, because he cannot remember the details of the lessons, and hence has probably not said them); (b) if they are improbable (e.g., Caius fears that he may have omitted Sext, although he recalls going to choir to chant at the regular times.)

665. Fears against an opinion are important, when they are not merely possible, but have such an appearance of truth that even a prudent man would consider them as worthy of support.

(a) Intrinsic signs of this solid probability are the good arguments by which the fear, or contrary of an opinion, is supported. Example: Titus after careful examination of conscience decides that he is not obliged to mention a theft in confession, because it happened just before his last confession; yet, he fears that he is obliged, because he does not remember having thought of restitution.

(b) Extrinsic signs of solid probability are the good authorities by whom the contrary of the opinion is defended. Example: Caius opines that he is not obliged to confess a calumny, because he is not certain that it is unconfessed; he fears that he is obliged, because St. Alphonsus, whose authority is great in Moral Theology, teaches that a grave sin must be confessed unless it is certain that it has been confessed already.

666. He who is moved by unimportant fears or difficulties is scrupulous, but not so he who hesitates in the face of an important difficulty. Examples: Balbus fears he may be guilty of murder, because he left a sick person for a moment and the latter unexpectedly died in his absence (scrupulous conscience). Sempronius fears he may be bound to restitution, because by his ridicule he made Titus lose his means of livelihood (disturbed conscience).

667. What is to be done by one who holds an opinion as to what he may or may not do here and now, but who has a serious fear that his opinion is wrong?

(a) If the fear persists as serious, when the means to remove it (such as consideration and consultation) have been duly resorted to, he should delay, if this is possible, or follow the safer course, if delay is not possible. Example: Titus must go to confession now, but he cannot recall whether or not a past theft was ever confessed; he thinks he is not obliged to mention it now, but is far from feeling certain about this, because of a serious doubt which he cannot resolve. The thing for him to do is to resolve to confess the theft as one that was perhaps unconfessed before.

(b) If the fear is removed or made unimportant, by direct means (such as theological argument from moral principles) or by indirect means (such as consultation or the use of reflex principles), the opinion may be followed. Example: If Titus, mentioned above, learns from his confessor or deduces from reliable reflex principles that he is not obliged to confess the theft, he may act with a safe conscience in following this decision.

668. The authority that may be safely followed by a lay person who holds an opinion, but fears that the opposite may be true, is that of anyone whom he knows to be pious, instructed and prudent; for, as it is impossible for him either to settle the question for himself or to remain in perpetual uncertainty, he must acquire certainty here as in other important affairs by consulting those who are expert and reliable. Hence, if the conscience is merely opinionative, a dependable adviser should be conferred with to make it certain.

(a) In the case of an accusing or excusing conscience, it is at least advisable that the doubtful sin be mentioned in confession, and especially by those who are not strict in their lives and who are inclined to judge their own acts and motives with leniency.

(b) In case of a forbidding or permitting conscience, it is necessary that one seek reliable information where it can be had, as from parents or teachers, and if these cannot give it, from a pastor or confessor or other priest. Example: Sempronius thinks he has a right to drink a glass of wine now and then to be sociable; but he fears he has no right to do so, as the drink occasions excitement or foolish remarks, and sometimes makes it difficult for him to get to his home safely.

669. The authority that may be safely followed by confessors and other priests in resolving important doubts against a moral judgment is as follows:

(a) If the opinion is supported as morally certain by all or nearly all of the approved text-books on moral teaching, it may be followed; for surely there would not be such unanimity, if the objections were really formidable.

(b) If the opinion is supported as morally certain by a goodly number (say, six or seven) of those who are considered as preeminent in Moral Theology, and who independently arrived at the same conclusion, it may be followed; for the judgment of many is better than that of one, and the certainty of authorities should prevail over the doubt of one who has not the same authority.

(c) If the opinion has the support as certain of only one theologian, it may be followed without further investigation, if he has received special mention from the Church as an authority and a safe guide. Thus, the Holy See has expressly declared that the doctrine of St. Alphonsus may be safely followed by confessors, and the approbation given to St. Thomas Aquinas as Universal Doctor makes his word more convincing than a contrary argument based on one’s own reasoning. Of course, this does not mean that these or any other private Doctors are infallible in their judgments, or that one should not depart from their teaching in a point where the Church has decided against them, or where there is a manifest reason for doing so; it simply means that they are so conspicuous among moralists for the correctness of their teaching that one who is in doubt may safely follow them unless the contrary is known to him.

670. But one may be unable to settle one’s difficulty by appeal to authority, as such, as in the following instances: (a) when the particular case to be decided is not considered at all in text-books, or is not considered under the circumstances that exist; (b) when the authorities speak hesitatingly about the question, and say that the opinion in question is at most probable, etc.; (c) when the authorities are about equally divided, as when a few great names are opposed to many names of inferior rank, or when those who are equal in knowledge so disagree that half are on one side, half on the other. In counting authorities, however, it is not always easy to decide who should be included, as a writer may himself be arguing from the authority of an individual or of a school, and thus he is not a distinct witness in favor of what he holds.

671. When a priest or other person sufficiently instructed in theology is not able to change through recourse to authority an opinionative or doubtful conscience into a certain conscience, he can still obtain certitude: (a) directly, by reexamining the question diligently and with entire impartiality, until he has discovered reasons strong enough to settle it convincingly one way or the other; (b) indirectly, by submitting the question to the arbitrament of a reflex principle that really appears true to him, and permitting it to decide between the opinion and the objection, or between the contending doubts.

672. The Moral Systems.—There are two general systems regarding reflex moral principles:

(a) Tutiorism, which teaches that the only principle which can change uncertainty into certainty is: “When one is undecided between the safer and the less safe, he must always choose the safer,” because only what is safer excludes the uncertainty of sinning;

(b) Anti-tutiorism, which teaches that the principle given above is true in a few exceptional cases on account of special reasons, but untrue as a rule. The general principle which it substitutes for that of Tutiorism is: “When one is undecided between the safer and the less safe, one may choose the less safe if it is morally certain.”

673. Of two moral judgments that are compared, it must be noted:

(a) that one is safer which departs more from the danger of sin by deciding for the stricter side. Example: In doubt whether a law exists, whether it obliges in a present case, whether its obligation is grave, the safer opinion is that which holds for the affirmative;

(b) that moral judgment is more likely which is supported by stronger arguments. Example: That a law has ceased, or does not apply in a certain case, or does not oblige under sin, is a more likely opinion if the arguments in its favor outweigh those against it.

674. Thus, it may happen that an opinion which is safer is less likely. Example: The opinion that the precept of repentance obliges under pain of new sin from the moment a sin is committed is safer, but less likely than the opposite opinion.

675. Danger of sin is twofold. (a) Danger of formal sin (see 249, 258) is a risk taken which involves, not only that an act may be unlawful, but that the doing of it may be unlawful. Example: Caius eats meat, doubting whether the day is one of abstinence and whether he is obliged to abstain or not. (b) Danger of material sin (see 249, 258) is the danger that an act may be unlawful, not in the concrete or as to its performance, but in the abstract as to itself. Example: Titus is unable to discover whether this is a day of abstinence, but he is of the opinion that it is not. Hence, he takes meat, arguing that, while this may be a violation of the law, he himself is not guilty of sin, since he feels that he has a right to eat meat under the circumstances.

676. Tutiorism.—This system has been condemned by the Church, and with good reason, for the following motives:

(a) If by that which is safer, Tutiorism intends that which is better, it contradicts the Gospel, which distinguishes between counsel and precept (see 364 sqq.), commanding what is good, but only recommending what is better.

(b) If by that which is safer Tutiorism means that which favors law against liberty, it imposes an intolerable yoke on the consciences of men; for, while law obliges only in so far as it is promulgated and known, Tutiorism would bind one to observe, not only what was not known to be obligatory, but what was held to be most probably not obligatory.

677. A modified form of Tutiorism taught: “When one is undecided between the safer and the less safe, one must choose the safer, unless the less safe is most probable.” This system has not been censured by the Church, but Catholic theologians with hardly an exception have rejected it, for the following reasons:

(a) Most probable, as understood by the defenders of this system, is that which has such likelihood and such appearance of truth as to remove every probable danger of even material sin. Thus, in reality this system requires absolute certitude and agrees with the rigorous tenet of Tutiorism that even a most probable opinion against the law may not be followed.

(b) Most probable, as commonly understood, is that side of a question which so far excels the other side that no answer can be given to any of its arguments, while all the arguments of the other side can be answered. To require this in moral difficulties is to require the impossible, for even the greatest theologians have to be content at times with less.

678. We are obliged always to follow a safe course, that is, not to expose ourselves to the danger of formal sin (see 249, 258); but Tutiorism errs when it teaches that we are also obliged always to follow the safer or safest course, that is, never to expose ourselves even to the danger of material sin. There are cases, however, when we are obliged (because some law requires it) to follow a safer course, that is, not to expose ourselves or others to some great harm. Thus, we must follow the safer side in the following cases:

(a) when there is question concerning something essential for the salvation of ourselves or of others, for the law of charity forbids that any risk be taken in this supremely important matter. Example: Titus instructs the dying Caius only concerning the existence of God and of the future life. He should also instruct him about the Trinity and the Incarnation, which is the safer course, since it is more probable that an explicit faith in these two mysteries is a condition of salvation;

(b) when there is question of some great spiritual loss or gain for ourselves or others, for justice or charity forbids that we take chances in such affairs. Examples: Sempronia doubts whether she is excused from the law of abstinence, and whether she will be guilty of sin if she eats meat. Caius doubts whether attendance at a certain school will do harm to the religion of his son. Balba doubts whether she is bound to inquire about the truth of her sect. As long as their serious doubts remain, these persons should follow the safer course;

(c) when there is question of the validity or invalidity of a Sacrament, for the virtue of religion requires that the Sacraments be administered with fidelity, and be not exposed to the peril of nullity. Example: It is not lawful to consecrate matter that has probably been substantially adulterated;

(d) when there is question of some temporal good or evil to oneself or another, and one is certainly obliged to promote the former or prevent the latter. Examples: Caius suspects that a drink before him is deadly poison; Titus suspects that an object at which he is preparing to shoot is a human being. Neither may disregard his suspicion, even if its contrary is more probable, because the safer side must here be taken. The Fifth Commandment forbids one needlessly to imperil one’s own or another’s life.

679. In emergency one may expose a Sacrament to nullity by taking a course that is less safe for the Sacrament, but safer for the subject, relying on the axiom that the Sacraments are for men, and not men for the Sacraments. Example: Titus is called to baptize the dying Caius. No water can be procured except rose water, whose sufficiency is doubtful. Titus not only may, but should, use the doubtful matter, since no other can be had.

680. Laxism.—The extreme opposite of Tutiorism is Laxism, whose principle is: “When one is undecided between the safer and the less safe, one may choose the less safe, if it is only slightly or uncertainly probable,” because whatever seems at all probable may be prudently followed, and so forms a certain conscience. Example: According to Laxism, one would be justified in following an opinion, because it was defended by one theologian, even though he was of little authority.

681. This system has been condemned by the Church for the following reasons:

(a) It is contrary to the teaching of the Gospels and of the Fathers, which requires one to observe the laws of God with understanding and diligence;

(b) It leads to corruption of morals. The Laxists of the seventeenth century were called in derision those “who take away the sins of the world,” and it was against their loose teachings that Pascal inveighed;

(c) Its argument is of no value, for no prudent person would feel that he should follow what was only slightly above the improbable, or that a law should be deemed uncertain because an opinion of uncertain probability could be quoted against it.

682. The true system of reflex principles will lie between the extremes of Tutiorism and Laxism. As already said, these two doctrines have been censured by the Church; but there are other systems that are moderate, and that are permitted by the Church and defended by theologians. These systems are:

(a) Probabiliorism, whose principle is: “When one is undecided between the safer and the less safe, one may choose the less safc only when it is more probable”;

(b) Equiprobabilism, whose doctrine is: “When one is undecided between the safer and the less safe, one may choose the less safe only when it affirms the non-existence of the law, and is at least equally probable with the opposite”;

(c) Probabilism, whose doctrine is: “When one is undecided between the safer and the less safe, one may choose the less safe whenever it is certainly and solidly probable”;

(d) Compensationism, whose doctrine is: “When one is undecided between the safer and the less safe, one may choose the less safe whenever it is certainly and solidly probable, and there is a proportionate reason to compensate for the risk taken.”

683. Probabiliorism.—The arguments in favor of Probabiliorism are as follows:

(a) extrinsic or from authority. This system is more ancient, and, when the controversy over systems began in the seventeenth century, this was the one that was most favored by the Church and theologians;

(b) intrinsic and direct. An essential note of certitude is that it should exclude all doubt, for as long as doubt remains there is only opinion. But one who is undecided cannot exclude all doubt, unless the arguments against the doubts not only balance, but outweigh the latter (i.e., unless one has greater probability on one’s side). Hence, he who acts against the safer, which is always certain enough, when his own opinion is not more probable, acts with an uncertain conscience;

(c) intrinsic and indirect. In all other matters a man is not prudent if he assents to that which is less safe and less probable. Thus, in things speculative no scholar would think of accepting a theory which to his knowledge was further removed from the truth; in things practical no man of common sense would prefer a road that seemed less likely to lead to his destination. But we should not be less prudent about the good than we are about the true and the useful. Hence, in doubt we should always decide in favor of the law, unless the arguments for liberty are more convincing.

684. The answers given to the above arguments are:

(a) Probabiliorism is not more ancient as a system, since none of the moral systems were formulated before the sixteenth century; if Patristic and medieval authorities can be quoted who decided cases probabilioristically, others who were contemporary can be named who decided according to milder principles. Moreover, the passages cited are frequently obscure, and do not necessarily bear a Probabilioristic sense. That Probabiliorism enjoyed more favor at the beginning of the controversy is not wonderful, since other systems were more or less identified with Laxism, and the question at issue had not been studied thoroughly. Today Probabiliorism has few defenders.

(b) That which is more probable by far, or most probable, does overcome all doubt, and is even speculatively certain; but he who would require the more probable in this sense does not differ from the Tutiorists spoken of above. That which is more probable, but not to a notable extent, does not exclude all doubt, for the very definition of the more probable is “that judgment which appears more likely to be true than another, but which does not exclude all fear that the other may be true.” Hence, if Probabiliorism calls for the notably more probable, it does not differ from Tutiorism; if it calls for the moderately more probable, it wrongly claims that there is no probability on the opposite side.

(c) The true is that which is in harmony with facts, the useful that which conduces to the obtaining of an end, the good that which is in conformity with law. Certainly, a man is not a prudent seeker of truth if he arbitrarily prefers the less to the more true-seeming, nor a prudent seeker of the useful if he chooses the less safe way of obtaining what is a necessary end; but a man can be a prudent seeker of the good, even though he prefers the less safe and less probable, when the law itself, the norm of good, does not demand more from him. Hence, one who makes a judgment according to the anti-Probabiliorist systems does not feel that he is yielding assent to what is speculatively less probable; but that he is making a decision that is practically certain; not that he is choosing a perilous way, but one that is absolutely safe.

685. Arguments against Probabiliorism.—(a) Theoretical Objection.—The principle of Probabiliorism that it is lawful to act against the safer side when the less safe side is more probable, cannot be justified except on the ground that invincible ignorance of obligation exists, and hence that the law does not oblige. But the same argument can be used in favor of milder systems; for even if the less safe side is only probable, it makes one invincibly ignorant that one is obliged. Hence, the basis of Probabiliorism is fatal to its own claims.

(b) Practical Objection.—A system for the direction of conscience should be so simple that it can be easily applied in the everyday affairs of life. Abstract questions may receive attention from moralists for days and months, but concrete cases have to be decided as a rule without delay. But Probabiliorism is such a complicated system that it is unsuited to everyday life. St. Alphonsus declares that he found by the experience of many years that this system cannot be profitably used in the guidance of souls, for it imposes an intolerable burden on both confessors and penitents. And how few are so skilled as to be able to decide quickly, without scruples, and correctly about the relative degrees of probability in opposite opinions!

686. Answers of the Probabiliorists.—(a) A probable opinion against the existence of obligation does not create invincible ignorance, but only doubt; nor does a more probable opinion against obligation create invincible ignorance, since it excludes the less probable opinion for obligation, and makes one assent unwaveringly and in good faith, even though erroneously, to the judgment that one is not bound.

(b) It is no more difficult to decide what is more probable than to decide what is equally probable, or truly and solidly probable; nor is the same skill and attention expected in all persons and cases, but each person must judge according to the best light he has, and each case must receive the measure of attention its importance calls for. If Probabiliorists may become scrupulous, may not Probabilists become lax?

687. The debate between Probabiliorism and its adversaries is not often heard today, as most modern moralists give their allegiance either to Equiprobabilism (a modified Probabiliorism) or to Probabilism.

688. Equiprobabilism.—The doctrine of Equiprobabilism is a middle way between Probabiliorism and Probabilism. Thus: (a) it agrees with Probabiliorism in holding that it is not lawful to follow the less safe, if the safer is more probable, or if the safer is equally probable, and the question is about the cessation of the law; (b) it agrees with Probabilism in holding that it is lawful to follow the less safe, if the safer is only equally probable, and the question is about the existence of the law.

689. The principle that “it is not lawful to follow the less safe, if the safer is equally probable and the question is about the cessation of the law,” is defended as follows by Equiprobabilists:

(a) In real doubt we should decide in favor of that side which is possession. But, when doubt is about the cessation of a law, the law is in possession; for there is no question that it was made. Therefore, in such a doubt we should decide for the safer side, that is, that the law has not ceased.

(b) A certain obligation is not complied with by a doubtful fulfillment. But doubts about the cessation of the obligation of law usually arise from a probability that one has already fulfilled the law. Therefore in such cases we should decide that the law has not been fulfilled—that is, that its obligation has not ceased.

690. The Probabilists reply that: (a) it is not true that, in equiprobability about the cessation of law, the law is in possession; for liberty is naturally prior to law, and hence has possession in doubt; (b) nor is it true that an obligation that has probably been complied with or removed is certain.

691. The Equiprobabilists answer: (a) liberty was in possession, until it was dispossessed by the making of the law; (b) an obligation that certainly existed must be held as certainly in existence, until the contrary is proved; whereas a fact, such as dispensation, abrogation, or fulfillment, is not proved if it is only probable.

692. The principle that “it is lawful to follow the less safe side, if the safer is only equally probable and the question is about the existence of the law,” is defended as follows by Equiprobabilists:

(a) In real doubt we should favor the side that is in possession. But when doubt is about the existence of a law, liberty is in possession; for liberty is prior to law. Therefore, in such doubt we may decide that there is no obligation.

(b) An uncertain law does not oblige, if one is invincibly ignorant of its existence. But, when there are equiprobable reasons against the existence of a law, one is invincibly ignorant of its existence. Therefore, in such cases one is not obliged.

693. The principle that “it is not lawful to follow the less safe side if the safer side is more probable,” is defended as follows by Equiprobabilists:

(a) In doubt improperly so called—that is, in that condition of mind in which there is no fluctuation between equal arguments, but only some indecision between the more and the less probable—we should decide in favor of the more probable, as being morally certain. Hence, it is not lawful to follow what is less safe and less probable.

(b) A law sufficiently promulgated obliges. But, when it is more probable that a law was made or is in force, such law is sufficiently promulgated to the conscience. Hence, the safer side must be followed, if it is more probable.

694. Probabilist Criticism of the Foregoing Arguments.

(a) If the excess of the more probable over the less probable is so great that the latter is only slightly or doubtfully probable, the more probable is equivalent to certitude; for certitude is assent without fear of the opposite, and the fear of the opposite in such a case would be so slight that it may be considered as non-existent. If the excess is not so great, the less probable remains solidly and certainly probable, and the more probable is not certitude, but opinion (that is, assent with fear of the opposite). The Equiprobabilists are speaking of greater probability in the second sense, and hence they are wrong when they identify it with certitude (see above, 654).

(b) A law must be so promulgated to the conscience that one knows the law or could know it with sufficient diligence; it does not suffice that one can get no further than opinion. It would be unreasonable to oblige one to observe not only what is the law, but also what seems to be the law. Now, he who has only more probable opinion that he is bound by some law, does not know that such obligation exists; he only knows that it seems to exist.

695. Reply of the Equiprobabilists.-(a) The more probable always removes the appearance of truth from the less probable. Hence, he who recognizes an opinion as more probable can assent to it without any fear of error.

(b) One who holds it as more probable that he is obliged by a certain law, does not know for certain that he is obliged by reason of that law; but he does know for certain that he is obliged by reason of a higher law. Superior to every particular law is the general law that nothing may be done that will deprive law of its efficacy. But law loses its efficacy if each one is free to decide that he is not bound even when the greater weight of probability is to the contrary.

696. General Arguments in Favor of Equiprobabilism.—(a) From Authority.—St. Alphonsus Liguori, who holds a unique place in the Church as a moralist, preferred Equiprobabilism to every other moral system; and his views are followed not only by his own Congregation, the Redemptorists, but by many others.

(b) From Comparison with Other Systems.—Truth lies midway between extremes; for truth is lost either by exaggeration or by defect. But Equiprobabilism is a happy medium between Probabiliorism inclining to Rigorism, and Probabilism inclining towards Laxism. Hence, the relation of Equiprobabilism to other systems is in its favor.

(c) From the Character of Its Teaching.—According to principles of justice universally admitted as true, a judge should pronounce sentence in favor of the more probable when there is evidence of unequal weight and in favor of that which is in possession when there is evidence of equal weight. But these principles ought to be of universal application. Therefore, Equiprobabilism does right in making these the guiding principles for the court of conscience.

697. Probabilist Criticism of these Arguments.—(a) St. Alphonsus is one of the greatest moral theologians of the Church. Whether in his later years (1762-1787) he taught Equiprobabilism, is a matter of dispute among those who are familiar with his writings. But there is no doubt that in his mature age (1749-1762), when he wrote his Moral Theology, he was a Probabilist.

(b) Probabilism can likewise claim that it stands midway between the extremes of Rigorism (represented by Probabiliorism and Equiprobabilism), on the one side, and of Laxism, on the other side.

(c) The principle of possession invoked by Equiprobabilism applies to matters of justice, because there is a presumption that he who holds property has a right to it, and also because human laws must favor him who is in possession, lest property rights be left uncertain and disputes be multiplied. The principle of possession does not apply, however, to other matters; if the law obliged one yesterday, how can that create a presumption that it obliges one today, if one has good reasons for thinking the obligation has ceased? And as for human ordinances, while they have jurisdiction over external goods and may award them in case of doubt to the possessor, they have not, and have never claimed, the right to make the principle of possession a rule for solving all difficulties about duty.

The principle of Probabiliorism for which the Equiprobabilists claim the authority of judicial practice certainly does not apply to criminal cases, for in these preponderance of evidence against an accused is not to be followed if there is a reasonable doubt. In civil cases judges apply the principle of probabiliorism, but it does not follow that conscience should do the same, for the circumstances are different. The judge is seeking to decide which of two litigants has the more likely claim, and hence he is bound to declare for the side that has stronger evidence. Conscience is seeking to decide whether an obligation is certain or uncertain, and hence it is not obliged to decide for obligation when this is more probable, but still not certain.

698. Answer of Equiprobabilists to this Criticism.—(a) Granted that St. Alphonsus once held Probabilism, he rejected it later emphatically, and when dying declared that his former defense of Probabilism was the only thing that gave him anxiety.

(b) Equiprobabilism is further removed from Rigorism than Probabilism is from Laxism. It hears both sides of the question—that for liberty and that for law—before it decides. Probabilism is satisfied to hear one side, that for liberty; or at least it does not compare the two sides.

(c) The principle of possession is applied more strictly in cases of justice; for, since justice implies a more exact equality and a more rigorous right than other virtues (see 154), disputes in matters of justice demand stronger proofs. But every virtue renders to someone his due, and hence there is no reason why principles applicable to justice should not be applicable to other virtues also. The principle of Probabiliorism, likewise, is just as applicable to the court of conscience as to the civil court, since in both courts the aim is to get the truth as nearly as possible.

699. General Arguments Against Equiprobabilism.—(a) Theoretical Objection.—If we judge Equiprobabilism by its arguments, we find it unconvincing, for that which is old in it does not agree with that which is new, and that which is new argues equally well for Probabilism. Thus, the old arguments for Probabiliorism mean in the last analysis that the greater probability deprives the opposite side of all solid probability; logically, then, one should conclude that equal probability deprives both sides of all solid probability, since one neutralizes the other. The new arguments are drawn from the principles that in doubt one should decide in favor of the side in possession, that a doubtful law does not oblige, etc.—all of which principles, as we shall see, favor Probabilism.

(b) Practical Objection.—If we judge Equiprobabilism by its adaptibility for use, we find it wanting. A moral system should be one that can be easily understood and applied, otherwise it is unworkable and useless. But Equiprobabilism is so complicated and abstruse that even the professional theologians who hold it are often at a loss how to apply it, and are found to give inconsistent decisions. How can it be expected, then, that anyone else will be able to decide whether the law or liberty is possession, whether the degree of probability on one side is greater than or equal to that on the other, whether the question has to do with the existence of the law or its cessation, etc.?

700. Replies of the Equiprobabilists.—(a) The old (i.e., probabilioristic) principles of Equiprobabilism are not contrary to the new. A more probable opinion not only balances the opposition by its equal arguments, and thus puts away doubt, but it also wins assent by the surplus in its favor, and thus certitude is had. When the two opposites are equally probable, there is a state of true doubt, but certitude is had by recourse to the principles of possession and doubtful law. These principles proper to Equiprobabilism do not favor Probabilism, if one is impartial in one’s use of them, and willing to use them against as well as for liberty.

(b) Equiprobabilism is not more difficult in its application than Probabilism. It does not require that one determine minutely and exactly the greater or equal probability of the arguments for law and for liberty, or that one devote extraordinary diligence to the solution of the problem. All it requires is that one consider the matter seriously, weigh the arguments on both sides impartially, and decide to the best of one’s ability which side appears to be more probable or to have the presumption in its favor.

701. Probabilism.—The meaning of Probabilism can be seen from a comparison with the opposite systems. (a) Unlike Probabiliorism and Equiprobabilism, Probabilism does not require a greater or equal probability, but permits one to follow what is less probable; (b) unlike Laxism, it does not allow one to follow what is only slightly or uncertainly probable, or to apply the system to all cases of doubt.

702. A judgment is probable when it is supported by arguments that make it seem true, although there may remain reasons for doubt. Examples are conclusions based on analogy, on hypothesis, on the opinions of others, or on the calculus of probabilities.

703. Probability is of various kinds. (a) It is absolute or relative, according as the supporting reasons are grave, either when considered alone, or when compared with the objections. Even the Probabiliorists admit that an opinion that is merely probable may be followed, if it is solidly probable and there is no argument against it (see 649). (b) We have solid or slight probability, according as the supporting motives are or are not such as would move, if not convince, a prudent man—that is, a man who shows good judgment in most things. (c) We have certain or uncertain probability, according as a person is sure or not, after reasonable consideration, that the arguments seem valid and the opinion likely. (d) Probability is internal or external, according as the arguments are drawn from the matter at issue itself (i.e., from its nature, properties, causes, effects, etc.) or from the authority of the doctors who have defended an opinion.

704. Relative probability according to logicians remains even when a lesser is compared with a greater probability. (a) If the opposing arguments are drawn from different sources, the more probable does not attack the less probable, and hence does not weaken its probability. Example: An intrinsic argument has more weight than a mere appeal to authority, but it does not attack the opposite argument, and hence does not diminish its probability. (b) If the opposing arguments are drawn from the same source, each one weakens the opposite, since there is direct opposition. But the more probable does not destroy the less probable, since, in spite of the greater appearance of truth on the one side, there still remains room for the possibility that the other side may be true.

705. A moral judgment is solidly probable when the following conditions are present:

(a) For the judgment there must be an intrinsic or extrinsic argument that would be considered weighty by a prudent man. Example: An opinion that has the support of a universally acknowledged authority is strongly probable, whereas, if it has only the support of one obscure writer, it is only slightly probable.

(b) Against the judgment there must be no decisive argument from authority or reason. Example; The judgment that a certain course of action is lawful because St. Alphonsus permits it, is ordinarily solidly probable; it is not probable, however, if the opinion of St. Alphonsus (e.g., that Catholics may act as sponsors in non-Catholic baptisms) has been disallowed by the Church, or if the argument he uses (e.g., that concerning the amount that constitutes grave matter in theft, which reasons from conditions in his day) is not strong.

(c) The arguments for the judgment must retain their probability, if they are set over against the arguments for the opposite. Manifestly, if the arguments are all satisfactorily answered by the opposite side, the judgment based on them ceases to retain the appearance of truth. Probabilism does not require, however, that one determine the relative degrees of probability in opposite opinions.

706. It is not sufficient according to the Probabilists that another be certain of the probability of an opinion; but the person who follows the opinion must himself be certain that it is solidly probable.

707. Regarding the kind of authority necessary to make an opinion solidly probable from external evidence, Probabilism teaches:

(a) that absolute probability (that is, such a weight of authority as would appear strong even to the most learned) ought to be estimated by quality rather than quantity—by the learning, prudence, impartiality, and independent study of the authors, rather than by their numbers. If five distinguished moralists arrive by separate study at the same conclusion (i.e., that an opinion is probable), or if one of special reputation in a matter under question supports the probability of an opinion, the argument from authority is strong;

(b) that relative probability (that is, such a weight of authority as suffices for one who is unlearned, such as a child, a halfwit, an uneducated person) is had sufficiently through the word of only one person who is looked up to as a guide or instructor, such as a parent, confessor, or teacher.

708. Probabilism supposes that one regards the opinion one follows as truly probable, and that one is convinced that it is lawful to follow such an opinion. Hence, the system does not apply in certain cases.

(a) It does not apply to cases in which there is no probability on either side—that is, to cases of negative doubt (see 656 sqq.), whether the doubt be of law or of fact.

(b) Probabilism does not apply to cases in which there is only slight or uncertain probability for the less safe side. Example: Caius has heard that a certain novel opinion is defended by a recent author, but he is uncertain of the author’s standing as a theologian, and he realizes that the fact that a man has written a book does not make his ideas solidly probable.

(c) Probabilism does not apply to cases in which there is solid probability for the less safe side, but one doubts whether one can lawfully follow it; for it is always sinful to act with a doubtful conscience (see 641 sqq.). Example: Caius has read in a reliable work of theology that a person in certain circumstances, which are his own, is probably excused from Mass. But the word “probably” makes him uncertain whether he can follow this opinion.

709. For the above-mentioned cases, to which their principle does not apply, Probabilists refer to the rules for a doubtful conscience (see 656 sqq.). The following special rules are given for cases of negative doubt:

(a) If the doubt is one of law and insoluble, one is free to act; for it is a general principle that an act may be considered lawful, as long as there is no serious reason to the contrary. Example: Sempronius goes out into the country on Sunday afternoon. An opportunity to fish presents itself, but Sempronius begins to doubt whether there is or is not a church law against fishing on Sundays. As no argument for either side is known to him, he may act on the general principle that what is not forbidden is lawful.

(b) If the doubt is one of fact and insoluble, and a prohibitory law is involved, one is free to act; for it is commonly admitted that legislators do not intend their prohibitions, which are restrictions of liberty, to be interpreted with the utmost rigor. Example: Titus is eating a chicken dinner late on Thursday night when his watch stops. As he has no way of discovering the time, he does not know whether Friday or the end of the dinner will arrive first. He may continue the meal, making no undue delays.

(c) If the doubt is one of fact, and a preceptive law is in question, one must take reasonable precautions to settle the doubt; for the lawgiver wills that those who are subject to the law should make use of the ordinary means to learn the facts on which obligation depends (see above, 384). If the doubt remains insoluble, one may decide in favor of liberty; for it may reasonably be presumed that the legislator does not intend to obligate those whose obligation remains uncertain. Example: Caius doubts whether he has reached the age of sixty, when the obligation of fasting ends. He should try to discover his real age; but, if he can find no real proofs either for or against the age of sixty, he may decide in favor of sixty, if there are some indications that he is of that age.

710. The solutions given above for cases of negative doubt suppose that there is no other or higher law that forbids one to take the risk of deciding in favor of liberty. Hence, in the following instances one must decide against liberty:

(a) in negative doubts when the validity of acts is at stake. Example: Titus is uncertain whether the law requires the age of fourteen for a valid contract of marriage; he is also uncertain whether he is fourteen years old. The doubt of law and of fact does not excuse Titus from the law, if he wishes to marry. He must clear up the doubts, and if necessary he must secure a dispensation.

(b) in negative doubts when reasons of charity or justice forbid one to take risks. Example: Caius is uncertain whether he paid Sempronius for work done for him. He is bound to make inquiries about the matter.

711. Probabilism cannot be applied, therefore, when the mental state of the subject is doubt, weakly founded opinion, or practical uncertainty. But, even when one holds an opinion as solidly and certainly probable, one may not follow it as a moral guide, if there is something in the nature of the object or matter itself which forbids this.

(a) A probability of law favoring liberty may not be followed in those matters in which some natural, divine or human law requires one to follow the safer side (see cases enumerated above, 678, 661). Example: The following opinions are probable; that instruction regarding the Trinity and the Incarnation is not indispensable for salvation; that rye-bread is valid matter for the Eucharist. But in practice it would be unlawful to take the risk of following these opinions, except in cases of extreme necessity, when nothing else can be done.

(b) A probability of fact favoring liberty may not be followed so long as there remains nothing more than probability of fact; for, while the will of the lawgiver may on account of probability of non-obligation change one’s relation to the law from obligation to non-obligation, it does not change facts. Examples: On Friday Titus doubts whether a dish before him is meat or fish; probably it is meat on account of its appearance, probably it is fish on account of its odor. At night Fr. Caius is much fatigued, and doubts whether he has said Vespers. Probably he did not, because he cannot recall what feast will be celebrated tomorrow; probably he did, because he remembers having said Compline.

712. For probabilities of fact, to which as such their system does not apply, Probabilists offer the following solutions:

(a) In certain cases one may take from the doubt of fact its bearing on obligation, by recourse to the manifest will of the legislator as declared in the law itself or expressed through dispensation. Examples: While hearing confessions, Sempronius doubts whether his jurisdiction has already expired. He cannot recall the date of expiration, but, thinking the matter over, he sees that probably the date has not arrived. His difficulty is therefore solved, for the Code (Canon 209) supplies jurisdiction in cases of probability of fact. Titus and Caia wish to marry. There is a doubt whether or not they are first cousins, but it seems that probably they are not so related. Their difficulty is solved by obtaining a dispensation.

(b) In other cases one may change the probability of fact into a probability of law by recourse to a probable opinion or argument that under the existing doubt of fact the legislator does not wish the law to oblige. Examples: Titus, who has what is probably lawful food before him, argues with himself that it is not likely that the Church wills to put him to the expense, trouble, and loss of time required to order other food. Fr. Titus, who has probably said Vespers, argues that theologians of authority teach that, when there is a serious reason for thinking one has performed such an obligation, it may be presumed that the Church does not require more.

713. If a case of probability of fact on which obligation hinges cannot be solved by recourse to the expressed or inferred will of the lawgiver, one has no choice but to follow the safer side, for then, though it is probable that a certain thing is a fact, it is not probable that one has a right to act. Example: Sempronius, while hunting, sees an object moving in the bushes. The probabilities are that it is not a human being, but it is not probable that Sempronius has the right to risk homicide by firing at it.

714. Not all Probabilists use the principle of the presumptive will of the lawgiver for all cases of negative doubt; some employ different principles for different kinds of doubt, and sometimes arrive at other decisions than those given in the preceding paragraphs. Thus, they give such rules as the following:

(a) In negative doubt of law regarding the lawfulness of an act, use the principle that law or liberty should be followed according as one or the other is in possession (see 660). Example: He who has only slight reasons for thinking that a law exists, or that it is of grave obligation, or that it extends to his case, etc., may decide against the law. But he who has only slight reasons for thinking that a law has been abrogated, or that a dispensation has been granted, etc., must decide for obligation.

(b) In negative doubt of law regarding the validity of a past act, use the principle _that what was done is to be held as rightly done_. Example: He who has no reasons, or only trifling ones, for thinking that a Sacrament was not administered validly or received validly, should decide for validity.

(c) In negative doubts of fact, use the principles that one should judge according to what usually happens, or that facts must not be taken for granted but must be established, or that presumption favors that which has possession. Examples: If there is no good reason to think that a conscientious person gave consent to a temptation, one may decide for the negative, since that would usually be true. If there is no good reason to think that one has made a vow, one may decide for the negative, since the burden of proof is with the other side. If, in a question about fast and abstinence, it is uncertain whether or not a person has reached twenty-one years, or whether Friday has commenced, the presumption is for the negative, since liberty has been in possession; but if it is uncertain whether a person has reached the age of sixty or whether Friday has ended, the presumption is for the negative, since the law has been in possession.

715. Having discussed the cases to which Probabilism is not extended, we pass on to the cases to which it is applied. Probabilism is used in any and every case where speculative certainty as to what is lawful or unlawful is not had, but where there is only speculative probability against an opposite probability.

(a) Probabilism is used not only in probability of law, but also in probability of fact that can be reduced to probability of law, as was explained above (see 712).

(b) Probabilism is used in probability of law, whether or not the question be about the existence or the cessation of the law. There is probability against existence of law, when one has good reason to think that a law was not made or not promulgated, or that the time when it goes into force has not arrived, or that it does not apply to certain persons or circumstances, etc.; there is probability for cessation of law, when it is certain that a law did exist, but one has good reason to think that it ceased or was abrogated, that one is excused or dispensed from it.

(c) Probabilism is used in probability of law, whether the law in question be natural, divine or human—that is, in every case of law where invincible ignorance is possible (see 319 sqq., 356).

716. The claim of Probabilism is that, in all the cases given above, he who follows an opinion excusing him from obligation, may act with a practically certain conscience and be free of all moral guilt, if the opinion is theoretically and seriously probable. The arguments for this thesis are of two kinds: (a) extrinsic proofs, from the approval given Probabilism by the Church and the favor it has enjoyed among moralists; (b) intrinsic proofs, from the nature of law and obligation, and the superiority of Probabilism in practice.

717. Extrinsic Arguments.—(a) The Church gave explicit approval to Probabilism by praising the theological works of St. Alphonsus in which Probabilism is defended; she gave and continues to give implicit approval by the freedom she has granted to the teachers of this system from the days of Bartholomew Medina, its first expounder (1527-1581), down to the present. The Church even makes use of the principles of Probabilism in interpreting her own laws, as is evidenced by such rules of law as the following in the Decretals: “Things that are odious should be understood strictly, things that are favorable widely” (Rule 15); “Where the law is doubtful, follow the minimum” (Rule 30); “Where the lawgiver could have spoken more clearly, the interpretation should be against him” (Rule 57); “The kinder interpretation should be given penal laws” (Rule 89).

(b) In the Patristic and medieval periods Probabilism had not been scientifically formulated, but many of the Fathers and early Doctors solved cases probabilistically, and there are not a few passages in the great theologians before the sixteenth century which enunciate the same principles as those advocated by Probabilists. When the system was formulated by Medina in 1577, it met with universal favor among Catholic moralists, and, though it suffered an eclipse from the middle of the seventeenth to the middle of the eighteenth century, it has been growing in influence since the days of St. Alphonsus, and appears today to have recovered its former preeminence. Among its adherents are some of the greatest names in the history of theology, and it is not confined to any particular school or body.

718. Objections of Equiprobabilists.—(a) The praise given to St. Alphonsus by the Church reflects no glory on Probabilism, since the Saint rejected Probabilism and professed Equiprobabilism. Further, more than one Pope, and especially Innocent XI (1676-1689), has expressed a dislike for Probabilism, while the silence of others does not mean more than toleration. The legal axioms used by canonists apply to the external forum, and cannot be used equally in the forum of conscience. (b) Probabiliorism had the field before Probabilism, having been formulated and defended before Medina appeared, and it is that more ancient system that is represented today in a milder form as Equiprobabilism.

719. Answer of the Probabilists.—(a) St. Alphonsus teaches Probabilism in his Moral Theology, which is his chief work; if later, in his old age, he was an Equiprobabilist, it can be shown that the change was not free, but under compulsion. As to Pope Innocent XI, he is the only Pope who expressed disapproval of Probabilism, and even he refrained from any official pronouncement. The fact that hundreds of works written by Probabilists since the sixteenth century have not been censured or forbidden by the Church authorities, indicates more than mere toleration.

(b) Probabiliorism, as a systematized method, preceded Probabilism as a systematized method only by a brief interval, if at all. Before the 16th century neither of these systems had been formulated, and neither can make much of the argument of priority in time. As for Equiprobabilism, it is first seen in the writings of Christopher Rassler (about 1713) and of Eusebius Amort (1692-1775).

720. Intrinsic Arguments for Probabilism.—(a) Theoretical Argument.—An uncertain law does not oblige. But a law is uncertain if there is a solidly probable opinion against its existence, or for its cessation, even though the other side be equally or more probable. Therefore, he who follows such an opinion does not violate any obligation.

(b) Practical Argument.—Probabiliorism and Equiprobabilism impose on confessors and the faithful impossible burdens, since, as was explained above (see 683 sqq.), they require that one compare and weigh probabilities, decide whether or not possession is had by the law or by liberty, etc.; whereas Probabilism is simple and easily applied, requiring only that one be convinced that one’s opinion is really probable, and that one use it in good faith.

721. The proposition that an uncertain law does not oblige (saving cases of validity, etc., as above, 678), is defended as follows:

(a) If the uncertainty arises from the law itself, because it has not been clearly worded or sufficiently promulgated, the truth of the proposition is manifest, for the very nature of law requires that it be brought to the knowledge of those for whom it is made (see 285).

(b) If the uncertainty arises from the invincible ignorance of one who is subject to the law, the proposition is true in the sense that no one is a transgressor in the internal forum who fails against a law unwittingly (see 327, 489 sqq.). But an act that transgresses no law is lawful in conscience, for all that is not forbidden is lawful.

722. The adversaries of Probabilism offer the following criticism:

(a) As to the proposition that “an uncertain law does not oblige,” the use of this principle by Probabilism may be considered as a begging of the whole question; for what is in dispute is whether, in case a law is uncertain, there is or is not a higher law that requires one to decide for obligation. It can be shown, however, that there is such a higher law; for the legislator cannot be willing that his ordinances be at the mercy of every uncertainty or loophole which subtle minds can devise, and God cannot be willing that those who are subject to laws should expose themselves to sin by deciding against a law because it appears to them to be of doubtful obligation.

(b) As to the proofs given for that proposition, they proceed from an incomplete enumeration, for a law can be doubtful on account of vincible ignorance, as well as for the reasons given. And no one will maintain that vincible ignorance excuses.

723. The Probabilists reply: (a) The principle that “an uncertain law does not oblige,” cannot render law nugatory, since there is question here only of honest doubt, not of pretended or responsible ignorance. Neither can that principle expose one to the danger of formal sin (see 249), since it is supposed that he who follows it is convinced that it is true, and that he has the right to regulate his conduct by it. It does expose to the danger of material sin (see 249), since the law about which there is uncertainty may be existent; but we are not obliged to avoid every danger of material sin, else we should be under the intolerable necessity of fulfilling not only all certain, but all uncertain duties. Moreover, the danger of material sin is not avoided by any moral system except Tutiorism, since even equiprobable and more probable opinions may be false.

(b) The enumeration of cases of doubtful law is sufficient; for, as just remarked, only those cases are being considered in which one is judging about one’s duty in good faith.

724. The second proposition used above as the Minor of the argument for Probabilism—that “a law is uncertain whenever there is a solidly probable opinion against its existence or for its cessation”—is defended by the very definition of the term “uncertain.”

A thing is said to be accepted as certain when one yields it firm assent and has no serious misgivings that it may be false; hence, the uncertain is that which is not assented to firmly (the doubtful), or that which does not exclude serious doubts about its truth (matter of opinion). Now, a law whose existence or obligation seems likely, but against which there militates a solidly probable argument, is not so firmly established as to inhibit every prudent doubt. In other words, such a law is uncertain.

725. Criticism of the Argument in the Preceding Paragraph.—(a) The supposition on which the argument rests is false. It supposes that the interpretation of the legal axiom that “a doubtful law does not oblige,” should be drawn from the philosophical definition of the terms, whereas it should be drawn from the sense given it by other rules of law. Now, there are canonical rules which declare that in doubt one should follow that which has possession, or that which seems more probable. Hence, the axiom quoted by the Probabilists refers only to cases of negative doubt; the other two rules refer to cases of doubt in the wide sense, or to cases of opinion; otherwise, we should have to admit that these legal maxims are contradictory, one to the other. Thus, it appears that Probabilism is based on a principle formulated to solve difficulties of an entirely different kind from those which the system deals with.

(b) The argumentation itself is fallacious. It takes for granted that an opinion is certainly and solidly probable, not only when it has no opposite or when its opposite is less probable, but also when its opposite is equally or more probable. This cannot be. Solid probability on the other side of a question must create doubt about an opinion held, and so make it at best uncertainly probable or probably probable; while greater likelihood or presumption on the other side must make one’s own opinion appear imprudent and unworthy of a rational being, and therefore not solidly probable.

726. The Probabilists answer: (a) The two principles with reference to doubtful law are understood and proved by Probabilism by an analysis of the notions of obligation and incertitude (see 285, 654), and hence they apply to every case that is restricted to the question of probable lawfulness or unlawfulness.

The rules quoted against Probabilism—there are some that might also be quoted against Probabiliorism and Equiprobabilism—are opposed to it only in appearance, since they deal with matters that are outside its sphere (see 697). Thus, in civil cases when both ownership and possession are doubtful, the decision must be given for the more probable side, since the issue is not what is lawful, but what seems to be true. As to the principle of possession, it is not, as supposed, unfavorable, but favorable to Probabilism; since liberty, inasmuch as it is presupposed by obligation (for only those who have freedom can receive obligation), has priority and must be given the benefit of the doubt, whenever a strictly probable reason in its favor cannot be refuted.

(b) Solid probability for the law creates doubt of the truth of the opinion for liberty, but it does not create doubt of its probability; for truth is the agreement of one’s judgment with the facts, probability the appearance of such agreement on account of the arguments by which the judgment is supported. Hence, greater probability for law does not make uncertain the probability there is for liberty. Neither is it a sign of imprudence to accept the less probable, if one has sincerely and diligently sought the truth; for even the more probable may not be true, and the great majority of moralists hold that one is not obliged to follow it.

727. Criticism of the Pragmatic Test Offered by Probabilists.—Probabilism boasts of the ease with which it can be used (see 700, 720); but the ease with which it can be misused is greater still.

(a) Persons not inclined to piety must quickly fall into Laxism, if they make use of this system, for they will accustom themselves to find every sort of pretext to escape unwelcome duties by raising doubts and dignifying them with the name of probable opinions; they will follow, now one opinion, now its contrary, according as it suits their interests; they will become stubborn in their own views, and unwilling to change or accept instruction.

(b) Persons inclined to piety, if guided by Probabilist principles, will soon lose all interest in what is higher and better, and content themselves with the minimum; for in every case of uncertainty Probabilism permits one to choose what is less safe and less probable.

728. General Answer of the Probabilists to the Objections of the Preceding Paragraph.—(a) The history of Probabilism contradicts these objections. From its beginning to the present day it has been defended and followed by men noted for piety, who used kindness towards others, but were severe with themselves. While the principles of stricter systems have proved a torture both to confessors and penitents, no detriment to holiness is observed from the use of Probabilism.

(b) The nature of Probabilism refutes the objections in question. There is no system so good that it may not be perverted and turned to evil, and stricter systems have been converted into Tutiorism or Rigorism. But the logical and usual results of Probabilism are not a lowering of moral standards. If these evils follow it, they do so only when it is not rightly understood or not rightly applied.

729. The charges of a tendency to Laxism are thus answered:

(a) Probabilism holds that only learned theologians are judges of internal probability. Others must not decide for themselves, but must seek instruction from their spiritual guides who have competent knowledge. The moralists themselves must not be so wedded to their opinions that they are not always ready to change when they find they are wrong or learn that the Church does not admit their view.

(b) Probabilism permits one to use contrary probable opinions in different instances (e.g., to use for one will or testament the opinion that informality makes it invalid, and for another will the opinion that informality does not make it invalid); but it does not permit contrary opinions to be used in the same case for one’s advantage (e.g., to use the opinion that an informal will is valid, in order to secure an inheritance, and at the same time to use the opinion that it is invalid, in order to escape the payment of legacies).

(c) Probabilism does not sanction the use of a probable opinion, unless it has been examined without prejudice, and has been honestly judged to be of certain and solid value (see 708 sqq.). Neither does it approve of the conduct of those who put themselves voluntarily in a state of doubt. On the contrary, it considers such conduct as sinful, and as gravely so, if the matter be serious and if this occur frequently. Example; Titus is uncertain whether three hours remain before Communion time, and yet he takes some refreshment, and thus makes it doubtful whether he has the right to receive Communion. The principle that a doubtful law does not oblige will enable Titus to receive Communion, but it does not excuse him from venial sin in putting himself without cause in a state of doubt and in danger of material sin.

730. The charge of a tendency to minimism in spiritual matters is thus answered: Probabilism deals only with what is lawful, not with what is better; it aims to show only what one may do without sin, not what one ought to do in order to become perfect. Hence, it is used when there is question of imposing obligations, or of deciding whether a certain course is lawful; for in these matters one must be kind, lest by exceeding one’s authority one drive others to sin; but it is not used when there is question of giving spiritual advice and direction, for here all should be exhorted to seek after progress in holiness.

731. Compensationism.—Between 1850 and 1880 a number of theologians, feeling that there were serious difficulties against all the systems up to then considered, developed a reformed or restricted Probabilism, which would not be open to the criticisms made against ordinary Probabilism, and yet would have those good qualities that make it preferable to the stricter systems. This new doctrine is called Compensationism, because it permits one to follow a probable opinion against the law only when there is present a sufficient reason to compensate for this course of action.

732. The following rules are, therefore, given as restrictions on the use of Probabilism: (a) the more serious or the more probable the doubtful law, the greater the reason must be to justify one in acting against it; (b) the higher and greater the good to be obtained from the exercise of freedom against a doubtful law, the less the reason that suffices for exercising freedom.

733. Illustrations of the Use of Compensationism.—(a) Titus, a poor man, is in uncertainty, through no fault of his own, about two debts. He thinks it more probable that he owes $10 to Sempronius, and 10 cents to Caius; but he believes it is really probable that he has paid both debts. He foresees that, if he offers the money to Sempronius, he will be subjected to serious quarrels and vexations, or at least that very bad use will be made of the money; while, if he offers to pay Caius, the latter may take some slight offense. He decides that there are proportionate reasons in each case to justify his following the less probable opinion.

(b) Fr. Titus thinks that a penitent is more probably bound to ask pardon of one whom he has offended. But he knows that, if he imposes the obligation, the present good faith of the penitent will be changed to bad faith, and he will refuse to do what is imposed. Fr. Titus decides, therefore, that it will be more profitable for the penitent if the less probable opinion—that there is no obligation—be followed.

734. The two chief arguments for Compensationism, which are also the two chief objections it makes against ordinary Probabilism, are:

(a) The obligation of a law depends on the knowledge one has about it. If one knows that the law exists, there is certain obligation; if one knows that the law does not exist, there is no obligation; if one holds it as probable that the law exists, there is probable obligation. Now, since one may not be excused from obligation unless there is a reason proportionate to the obligation itself (see 495), he who is under probable or more probable obligation must have a graver reason for using freedom than he who is under no obligation (against Probabilism), but he need not have as grave a reason as one who is under a certain obligation (against Probabiliorism). Hence, one may not act against a probable law, unless by so doing there is some good secured that compensates for the danger to which the right of the law is exposed.

(b) It is lawful to perform a good act from which an evil effect will result, only if one has a proportionally grave cause for permitting the evil effect (see 102 sqq.). But he who follows the opinion for liberty against a more probable or equally probable opinion for law, performs an act from which will probably result the evil of a material transgression of law. Therefore, one may not use Probabilism unless by so doing there is some good secured that compensates for the danger of material sin to which one exposes oneself.

735. Criticisms from the Probabilists.—(a) The dictum that a doubtful law obliges doubtfully cannot be applied, for in actual life there is no middle way between decision for the law and decision for liberty, unless it be indecision. The principle of Compensationism must mean, then, that we must always decide for a doubtful law (which is Tutiorism), or remain in suspense (which is no help to the one in doubt).

(b) The supposition that there must always be some special reason of good to offset the evil of the danger of material sin is not correct. For there always exists a compensation proportionate to the danger, namely, the exercise of liberty, a great gift of God, and the avoidance of the burden of fulfilling all uncertain obligations.

736. Reply of the Compensationists.—(a) The principle that a doubtful law obliges doubtfully means only that the reasons in favor of the law deserve some consideration, and should not be put aside unless one has some better reason than mere arbitrariness, self-will, or the intention to take always the easier way. There is no question of either Tutiorism or hesitation, but only of a prudent and honest facing of the fact that there are two sides to one’s doubt.

(b) It is not true that the exercise of liberty and the escape from the burden of uncertain obligations are always a sufficient compensation for the danger of material sin. For material sin is not only an evil in itself, as being a violation of law; it is also the source of many and great evils both to the individual and society, such as wrong habits acquired, scandal given, etc. Liberty is a great gift, but it should not become a cloak for malice. Neither is the foregoing of liberty so great an evil that one should not be willing to suffer it now and then in order to prevent the greater evils spoken of just above.

737. Other Objections Against the System of Compensation.

(a) From Authority.—Compensationism is of very recent origin, and it cannot be admitted that the right solution of moral difficulties was unknown before this new system appeared.

(b) From Reason.—It runs counter to the principle commonly accepted in the controversies of the systems, namely, that the decisive factor as to obligation in doubt is knowledge. For it introduces a new factor, that of sufficient reason or compensation.

(c) From Serviceability.—It is easy to say in the abstract that one should always have a suitable reason for adopting a probable opinion in favor of liberty. But, when one attempts to apply this rule to actual cases, difficulties innumerable arise (searchings of motives, comparison of probabilities, measuring of consequences, etc.), so that for use Compensationism is impossible, or impracticable.

738. Reply of Compensationists.—(a) Compensationism is an example of doctrinal progression from the implicit to the explicit. The principles on which it is based are found in the teaching and practice of the most ancient authorities.

(b) Sufficient reason is not a new principle, since it is admitted by all moralists for the case of double effect (see above, 102 Sqq.); its application to the solution of doubts of conscience is not an innovation, since the cases of doubt and of double effect are analogous.

(c) Compensationism is not intended as a system to be applied by those who have not sufficient theological training, but as a guide for moralists, directors and confessors. That it is not difficult, is clear from the fact that it is only an application of the commonly accepted principle of double effect, and that Probabilists themselves recommend it and make very general use of it, as if they instinctively recognized its necessity.

739. Practical Conclusions.—From the foregoing discussions one may deduce three rules for the guidance of those who are not expert theologians:

(a) If your state of conscience is certitude (i.e., if you are firmly convinced which way your duty lies), entertain no fears or scrupulous doubts, and, having done your part to understand your obligations, you need not hesitate to follow your conscience.

(b) If your state of conscience is imprudent assent (i.e., the acceptance of what you recognize as unlikely), or if it is suspended assent (i.e., a wavering between opposites), do not act blindly, but seek truth and decision.

(c) If your state of conscience is opinion (i.e., the acceptance of what you regard as likely though uncertain), consult your confessor or another competent theologian; if there is no time for this, decide for any course that seems true and prudent (see on perplexed conscience, 611 sqq.).

740. Regarding the respective merits and the use of the rival systems of conscience, the following conclusions may be drawn:

(a) If there is question of what is to be counselled, one should be a “Meliorist,” for the better and more perfect is more advisable than what is merely good or lawful. All Christians should be directed to aspire after holiness, but, if one is unwilling to follow a counsel, it should not be imposed on him as a precept. Naturally, of those in higher station higher things are required.

(b) As between doubt and certitude regarding obligations, one must be a “Certitudinist,” that is, one must resolve doubts or slight probabilities into direct or indirect certitude (as was explained above in 641 sqq.). If a doubt remains, one must for that case be a Tutiorist, that is, one must follow the safer side (as explained in 661).

(c) As between the safer and the less safe, one must be a Tutiorist, when some law requires this, as is the case when validity or supreme rights are at stake (as explained in 678, 679).

(d) As between the more likely and the less likely, one must be a Probabiliorist, when this is according to law, as is the case in civil suits where the preponderance of evidence must be followed (see 697).

(e) One may not follow either Tutiorism (see above, 676) as a general moral system, nor Laxism (see above, 681).

(f) If a probable opinion for liberty is opposed by no contrary probable opinion or by none whose arguments cannot be overcome, one is free to follow that opinion, as explained in 649, 703.

(g) If a probable opinion for liberty is opposed by an opinion that is less, equally or more probable, one is free to act according to the principles of Probabiliorism, Equiprobabilism, Probabilism or Compensationism, according to conviction.

741. As for the use of moral systems by confessors, the two following rules are generally admitted:

(a) If a penitent has formed his conscience according to one moral system, the confessor has no right to impose on him the opinion of a different moral system; for the Church allows liberty.

(b) If a penitent has not formed his conscience according to any moral system and seeks the answer to a moral doubt, the confessor should decide, not necessarily for what his own system declares lawful, but for what appears, all the circumstances being considered, to be most advantageous spiritually for the penitent. Example: Fr. Titus is a Probabilist, and he usually advises questioners to follow opinions that are less probable; while Fr. Caius, who is a Probabiliorist, always requires that such persons follow the more probable opinions. Both act unwisely. For persons who are better disposed, it will often be more profitable to follow what is more probable or favorable to obligation; for those Whose dispositions are less good, milder opinions may be recommended, lest the smoking flax of goodness that is in them be entirely extinguished. Neither is it right to impose as certain an obligation which the penitent, if he were acquainted with Moral Theology, would see is controverted.

742. In case of disagreement between confessor and penitent as to whether absolution may be given, whose opinion should prevail? (a) If the disagreement is concerned with matters about which the confessor himself has to judge (e.g., the disposition of the penitent, the requisite matter for absolution, etc.), the opinion of the confessor must prevail; for the act of judging is his own, and he must be guided therefore by his own conviction.

(b) If the disagreement is concerned with matters about which the confessor is not the judge (such as the controversies of schools and theologians), the confessor may not refuse absolution to a well-disposed penitent, just because the latter will not accept the opinion of his school or system. If it be manifest that the penitent’s opinion is false or improbable, absolution may be denied him, unless it seems more prudent to leave him in good faith.

PART II
SPECIAL MORAL THEOLOGY

743. In the First Part of this work, the means to man’s Last End were spoken of in a general way; the features that are common to all good acts—that they be human, morally deserving, directed according to law and conscience—were treated. In the present Part the means to the Last End will be discussed in particular, and we shall consider in turn the kinds of duties that are owed by all men and those owed by persons in special states of life.

Question I
THE DUTIES OF ALL CLASSES OF MEN

744. Good habits, specifically different, are all reducible to seven most general virtues (see 150, 151), and hence in studying these seven virtues, we shall at the same time study all the common duties of man.

745. The properties of the seven infused virtues are chiefly four:

(a) In the first place, these virtues may be increased: “This I pray, that your charity may more and more abound” (Phil, i. 9). The increase takes place _ex opere operato_ through the Sacraments, or _ex opere operantis_ through meritorious works—that is, whenever sanctifying grace, their root, is increased.

(b) A second property of the infused virtues is that they may be lost: “I have somewhat against thee, because thou hast left thy first charity” (Apoc., ii. 4); “Some have made shipwreck concerning the faith” (I Tim., i. 19). The loss is caused by the contrary of the virtue: faith is lost by disbelief, hope by despair; charity and the moral virtues are lost by any mortal sin, for they are built on sanctifying grace, which mortal sin destroys.

(c) A third property of the infused virtues is that they cannot be diminished directly. If we leave out of consideration their opposites (which, as just said, remove these virtues entirely), there is nothing else that can act directly upon them. Mere failure to exercise them cannot lessen them, since they are caused by divine infusion, not by human exercise; venial sin cannot lessen them, since it does not lessen grace on which they depend.

(d) A fourth property of the infused virtues is that they are diminished indirectly. Failure to practise them or venial sin does diminish the ease and fervor with which the acts of these virtues are exercised; and thus indirectly—that is, by preparing the way for acts that are directly contrary—neglect or venial sin diminishes the habits themselves.