Denzinger EN 3864
[From the Address of Pius XII on September 29, 1949, before the fourth international convention of Catholic physicians]
3323 Dz 2303 1. The practice of artificial fertilization, insofar as it concerns man, cannot be judged exclusively, or even principally, according to the norms of biology and medicine, neglecting moral and juridical norms.
2. Artificial fertilization outside of marriage is to be condemned purely and simply as immoral.
In fact, natural law and positive divine law demand that procreated new life be the fruit of marriage alone. Only marriage guards the dignity of spouses (especially of the wife, as far as this question is concerned), and their personal good. Only marriage of itself provides for the good and education of the child. Therefore, it follows that there can be no divergence of opinion among Catholics in condemning artificial fertilization outside the conjugal union. Offspring conceived in such a manner would be by the very fact illegitimate.
3. Artificial fertilization, which is effected within marriage but by an active element of a third party, is in the same way immoral, and as such is to be condemned absolutely.
Only spouses have a reciprocal right over the body to procreate new life, which right is exclusive and inalienable. The child also demands this. For upon him, who communicates new life to the child, nature itself by the force of this relationship imposes the obligation both of protecting and raising this offspring. Indeed, between the legitimate husband and the child procreated by the active element of the third party (even if the husband should consent) no bond of origin, nor any moral and juridical bond of matrimonial procreation exists.
4. As for the morality of artificial fertilization within marriage, let it suffice for the present for Us to call to mind the principles of the natural law; the mere fact that the end which is intended is actually achieved in this way does not make the use of this means lawful; and the desire of spouses (in itself, moreover, lawful) of having offspring does not yet prove sufficiently that the use of artificial fertilization, by which this desire is fulfilled, is licit.
It is an erroneous opinion which holds that marriage between persons incapable of contracting marriage because of the impediment of impotence can be rendered valid by the use of this means.
On the other hand it goes without saying that the active element is always procured illicitly by acts which are contrary to nature.
Although a priori new methods cannot be excluded merely because they are new, nevertheless, as far as artificial fertilization is concerned, not only is there need of the greatest circumspection, but it simply must be avoided. By these words We do not necessarily forbid the use of artificial means, which are destined only either to render the natural act easier or to bring it about that the completed act attain its end in a natural way.
Let it not be forgotten: only the procreation of new life, which takes place according to the will and order of the Creator, obtains to a truly perfect degree the ends intended by it. Such procreation corresponds at once to the corporal and spiritual nature and the dignity of the spouses and to the normal and happy development of the infant.
[Response of the Holy Office, December 28, 1949]
3874 Dz 2304 To this Supreme Sacred Congregation ... the question has been proposed:
"Whether, in judging matrimonial cases, baptism conferred in the sects of the Disciples of Christ, the Presbyterians, Congregationalists, Baptists, Methodists, when the necessary matter and form have been used, is to be presumed as invalid because of the lack of the required intention in the minister of doing what the Church does, or what Christ instituted; or whether it is to be presumed as valid unless in a particular case it is proven to the contrary." The reply: In the negative to the first part; in the affirmative to the second.
[From the Encyclical, "Humani generis", August 12, 1950]
3875 Dz 2305 The discord and departure from truth on the part of the human race in religious and moral affairs have always been a source and a cause of very painful grief to all good men, and especially to the faithful and sincere sons of the Church, and more than ever today when we perceive the very principles of Christian culture offended on all sides.
Indeed, it is no wonder that such discord and wandering have always flourished outside the fold of Christ. For although human reason, speaking simply, by its natural powers and light can in fact arrive at true and certain knowledge of one personal God who in His providence guards and directs the world, and also of the natural law infused into our souls by the Creator, nevertheless, not a few obstacles prevent man's reason from efficaciously and fruitfully using this natural faculty which it possesses. For matters which pertain to God and have to do with relationships between men and God, are truths which completely transcend the order of sensible things, and, when they are introduced into the action of life and shape it, demand devotion of self and self-abnegation. The human intellect, moreover, in acquiring such truths labors with difficulty not only on account of the impulse of the depraved senses and the imagination, but also of the desires which have their source in original sin. Therefore it happens that men in matters of this kind easily persuade themselves that what they do not wish to be true, are false or at least doubtful.
3876 For this reason divine "revelation" must be considered morally necessary, in order that those truths, which in the realm of religion and morals are not of themselves beyond the scope of reason, yet in the present con" dition of the human race, may be readily grasped by all with strong certitude and with no admixture of error.*
Yet on the other hand the human mind can sometimes experience difficulties in forming a certain judgment "of credibility" about the Catholic faith, although so many wonderful external signs have been disposed by God, through which, even by the natural light of reason alone, the divine origin of the Christian religion can be proven with certainty. For man, whether induced by prejudiced opinions or instigated by desires and evil will, can refuse and resist not only the evidence of external signs, which is pre-eminent, but also the supernal inspirations which God brings into our hearts.
Anyone who observes those who are outside the fold of Christ, can easily see the chief ways upon which many learned men have entered.
3877 There are those who contend that the so-called system of evolution, not yet irrefutably demonstrated within the scope of the natural sciences, and admitted imprudently and indiscreetly, extends to the origin of all things, and who boldly entertain the monistic and pantheistic theory that the whole world is subject to continuous evolution. Indeed, the supporters of communism gladly employ this theory, to bring out more efficaciously and defend their "dialectic materialism," casting out of mind every notion of God.
3878 Dz 2306 Such fictions of evolution, by which whatever is absolute, firm, and immutable, is repudiated, have paved the way for a new erroneous philosophy which, in opposition to "idealism," "immanence," and "pragmatism," has obtained the name of "existentialism," since it is concerned only with the "existence" of individual things, and neglects the immutable essence of things.
There is also a kind of false "historicism," which attends only to events of human life, and razes the foundations of all truth and absolute law, not only insofar as it pertains to the philosophical matters, but to Christian teachings as well.
Dz 2307 In such a great confusion of opinions as this it gives us some solace to note those who not rarely today desire to return from the principles of "realism," in which they had once been instructed, to the well-springs of truth revealed by God, and to acknowledge and profess the word of God as preserved in Holy Scripture. Yet at the same time We must grieve that by no means a few of these, the more firmly they cling to the word of God, that much more diminish human reason; and the more they exalt the authority of God who reveals, the more sharply they spurn the magisterium of the Church, instituted by Christ the Lord to guard and interpret the truths revealed by God. This indeed is not only in open contradiction to Sacred Scripture, but is proved false from actual experience. Often the very ones who disagree with the true Church openly complain about their own discord in matters of dogma, so that they unwillingly confess to the necessity of the living magisterium.
3879 Dz 2308 Indeed, Catholic theologians and philosophers, upon whom falls the serious duty of protecting divine and human truth, and of inculcating these in the minds of men, may not ignore or neglect these opinions which more or less stray from the straight road. Moreover, they should thoroughly examine these opinions, because diseases cannot be cured unless they have been rightly diagnosed; also because sometimes in false fabrications something of truth lies hidden; finally, because such theories provoke the mind to scrutinize and weigh certain truths, philosophical or theological, more carefully.
But, if our philosophers and theologians strive to gather only such fruit from these doctrines, after cautious examination, there would be no reason for the intervention of the magisterium of the Church. However, although We have found that Catholic doctors in general are on their guard against those errors, yet it is well established that there are not lacking today, just as in apostolic times, those who, in their extreme zeal for novelty and also in their fear of being held ignorant of those matters which the science of a progressive age has introduced, strive to withdraw themselves from the temperateness of the sacred magisterium; and thus they become involved in the danger of gradually and imperceptibly departing from the truth revealed by God, and of leading others into error along with themselves.
Indeed, even another danger is observed, and is more serious, since it is more concealed under the appearance of virtue. There are many who, deploring the discord of the human race and the confusion of minds, and roused by an imprudent zeal for souls, are moved by a kind of impulse, and burn with a vehement desire to break down the barriers by which good and honest men are mutually separated, embracing such an irenicism that, forgetting the questions that separate men, they not only seek to refute destructive atheism by common strength, but even to reconcile opposing ideas in dogmatic matters.
3880 And just as once there were those who asked whether the traditional study of apologetics constituted an obstacle rather than an aid to the winning of souls for Christ, so today there are not lacking those who dare proceed to the point of seriously raising the question whether theology and its method, as they flourish in the schools with the approval of ecclesiastical authority, ought not only to be perfected, but even to be entirely reformed, so that the king dom of Christ may be propagated more efficaciously everywhere in the land, among men of every culture, and of every religious opinion. If these men aimed at nothing else than the better adaptation of ecclesiastical science and its method to present day conditions and demands, by introducing a kind of new plan, there would be little reason to fear; but, burning with an imprudent irenicism, some seem to consider as obstacles to the restoration of fraternal unity those matters which rest upon the very laws and principles given by Christ, and upon the institutions founded by Him, or which are the bulwarks and pillars of the integrity of faith, by the collapse of which all things are united to be sure, but only in ruin. . . .
3881 Dz 2309 As far as theology is concerned, some propose to diminish as much as possible the significance of dogmas, and to free dogma itself from the manner of speaking long accepted in the Church, and from the philosophical notions which are common among Catholic teachers; so that in explaining Catholic doctrine there may be a return to the manner of speaking of the Holy Scripture and of the Holy Fathers. They cherish the hope that the time will come when dogma, stripped of the elements which they say are extrinsic to divine revelation, may be profitably compared with the dogmatic opinions of those who are separated from the unity of the Church; and in this way gradually a mutual assimilation will be reached between Catholic dogma and the principles of the dissidents.
3882 Dz 2310 In addition, when Catholic doctrine has been reduced to this condition, they think that the way is paved to satisfy present-day needs, by expressing dogma in the terms of contemporary philosophy, whether of "immanence" or of "idealism," or "existentialism," or of any other system. Certain more daring persons contend that this can and ought to be done for this reason, because they maintain that the mysteries of faith can never be expressed by notions that are adequately true, but only by so-called "approximative" notions, always changeable, by which truth is indicated to a certain degree, but is also necessarily deformed. So they think that it is not absurd, but quite necessary that theology in place of the various philosophies which it has used as its instruments in the course of time, substitute new notions for old ones, so that in ways that are different, and even in some degree opposite, yet possessing the same value, as they say, render the same divine truths in a human way. They add also that the history of dogmas consists in presenting the various successive forms with which revealed truth has clothed itself, according to the different doctrines and opinions which have arisen in the course of the ages.
3883 Dz 2311 But it is clear from what we have said that such endeavors lead not only to dogmatic "relativism," as it is called, but actually contain it; indeed, the contempt for the doctrine as commonly handed down, and for the phraseology by which the same is expressed, more than sufficiently bear this out. Surely there is no one who does not see that the phraseology of such notions not only as employed in the schools but also by the magisterium of the Church herself, can be perfected and polished; and, besides, it is noted that the Church has not always been constant in employing the same words. It is also evident that the Church cannot be bound to any system of philosophy which flourishes for a brief period of time; for, what has been set in order over many centuries by common consent of Catholic teachers, in order to achieve some understanding of dogma, without doubt does not rest on so perishable a foundation. Rather they are based on principles and notions derived from a true knowledge of created things; and surely in deriving this knowledge, truth divinely revealed has through the Church illumined the mind like a star. Therefore, it is no wonder that some such notions were not only employed by ecumenical councils but also so sanctioned that it is not right to depart from them.
Dz 2312 Therefore, to neglect, or to reject, or to deprive so many great things of their value, which in many instances have been conceived, expressed, and perfected after long labor, by men of no ordinary genius and sanctity, under the watchful eye of the holy magisterium, and not without the light and guidance of the Holy Spirit for the expression of the truths of faith ever more accurately, so that in their place conjectural notions may be substituted, as well as certain unstable and vague expressions of a new philosophy, which like a flower of the field exists today and will die tomorrow, not only is the highest imprudence, but also makes dogma itself as a reed shaken by the wind. Moreover, the contempt for the words and ideas which the scholastic theologians customarily use, tends to weaken so-called speculative philosophy, which they think is void of true certitude, since it rests on theological reasoning.
3884 Dz 2313 Surely it is lamentable that those eager for novelty easily pass from a contempt for scholastic theology to a neglect, and even a disrespect for the magisterium of the Church, which supports that theology by its authority. For, this magisterium is considered by them as a hindrance to progress and an obstacle to science; indeed, by certain non-Catholics it is looked upon as an unjust restraint by which some learned theologians are prevented from pursuing their science. And, although this sacred magisterium, in matters of faith and morals, should be the proximate and universal norm of faith to any theologian, inasmuch as Christ the Lord entrusted the entire deposit of faith to it, namely, the Sacred Scriptures and divine "tradition," to be guarded, and preserved, and interpreted; yet its office, by which the faithful are bound to flee those errors which more or less tend toward heresy, and so, too, "to keep its constitutions and decrees, by which such perverse opinions are proscribed and prohibited,''* is sometimes ignored as if it did not exist. There are some who consistently neglect to consult what has been set forth in the Encyclical Letters of the Roman Pontiffs on the character and constitution of the Church, for the reason that a certain vague notion prevails drawn from the ancient Fathers, especially the Greek. For the popes, as they repeatedly say, do not wish to pass judgment on those matters which are in dispute among theologians, and so there must be a return to the early sources, and the more recent constitutions and decrees of the magisterium are to be explained from the writings of the ancients.
Even if perchance these things seem to have been wisely said, yet they are not without error. It is true that, in general, the Pontiffs grant freedom to theologians in those matters which are disputed with varying opinions, but history teaches that many things, which formerly were subject to free discussion, later cannot permit any discussion.
3885 It is not to be thought that what is set down in Encyclical Letters does not demand assent in itself, because in this the popes do not exercise the supreme power of their magisterium. For these matters are taught by the ordinary magisterium, regarding which the following is pertinent: "He who heareth you, heareth me." (Lc 10,16); and usually what is set forth and inculcated in the Encyclical Letters, already pertains to Catholic doctrine. But if the Supreme Pontiffs in their acts, after due consideration, express an opinion on a hitherto controversial matter, it is clear to all that this matter, according to the mind and will of the same Pontiffs, cannot any longer be considered a question of free discussion among the theologians.
3886 Dz 2314 It is also true that theologians must always have recourse to the sources of divine revelation; for it is their duty to indicate how what is taught by the living magisterium is found, either explicitly or implicitly, in Sacred Scripture and in divine "tradition." In addition, both sources of doctrine, divinely revealed, contain so many and such great treasures of truth that they are in fact never exhausted. Therefore, the sacred disciplines always remain vigorous by a study of the sacred sources, while, on the other hand, speculation, which neglects the deeper investigation of sacred deposit, as we know from experience, becomes sterile. But for this reason even positive theology, as it is called, cannot be placed on equal footing with merely historical science. For, together with these sacred sources God has given a living magisterium to His Church, to illumine and clarify what is contained in the deposits of faith obscurely and implicitly. Indeed, the divine Redeemer entrusted this deposit not to individual Christians, nor to the theologians to be interpreted authentically, but to the magisterium of the Church alone. Moreover, if the Church exercises this duty of hers, as has been done again and again in the course of the ages, whether by ordinary or extraordinary exercise of this function, it is clear that the method whereby clear things are explained from the obscure is wholly false; but rather all should follow the opposite order. Therefore, Our predecessor of immortal memory, Pius IX, teaching that the most noble function of theology is to show how a doctrine defined by the Church is contained in the sources, added these words, not without grave reason: "By that very sense by which it is defined." * . . .
3887 Dz 2315 But to return to the new opinions which We have touched upon above, many things are proposed or instilled in the mind (of the faithful) to the detriment of the divine authority of Sacred Scripture. Some boldly pervert the meaning of the definition of the Vatican Council, with respect to God as the author of Sacred Scripture; and they revive the opinion, many times disproved, according to which the immunity of the Sacred Writings from error extends only to those matters which are handed down regarding God and moral and religious subjects. Again, they speak falsely about the human sense of the Sacred Books, under which their divine sense lies hidden, which they declare is alone infallible. In interpreting Sacred Scripture they wish that no account be taken of the analogy of the faith and of "the tradition" of the Church, so that the teaching of the Holy Fathers and of the holy magisterium is to be referred, as it were, to the norm of Sacred Scripture as explained by exegetes in a merely human manner, rather than that Sacred Scripture be interpreted according to the mind of the Church, which was established by Christ the Lord as the guardian and interpreter of the whole deposit of truth revealed by God.
3888 Dz 2316 And besides, the literal sense of Sacred Scripture and its exposition, as elaborated by so many great exegetes under the watchful eye of the Church, according to their false opinions, should yield to the new exegesis which they call symbolic and spiritual; by which the Sacred Books of the Old Testament, which today are as a closed source in the Church, may be opened sometime to all. They declare that by this method all difficulties vanish, by which they only are shackled who cling to the literal sense of Scripture.
3889 Surely, everyone will see how foreign all this is to the principles and norms of interpretation rightly established by Our predecessors of happy memory, Leo XIII in the Encyclical Letter "Providentissimus," Benedict XV in the Encyclical Letter, "Spiritus Paraclitus," and also by us in the Encyclical Letter, "Divino afflante Spiritu."
3890 Dz 2317 And it is not strange that such innovations, as far as pertains to almost all branches of theology, have already produced poisonous fruit. It is doubtful that human reason, without the aid of divine "revelation" and divine grace, can demonstrate the existence of a personal God by arguments deduced from created things; it is denied that the world had a beginning, and it is disputed that the creation of the world was necessary, since it proceeds from the necessary liberality of divine love; eternal and infallible foreknowledge of the free actions of men is likewise denied to God; all of which, indeed, are opposed to the declarations of the Vatican Council.*
3891 Dz 2318 The question is also raised by some whether angels are personal creatures; and whether matter differs essentially from spirit. Others destroy the true "gratuity" of the supernatural order, since they think that God cannot produce beings endowed with intellect without ordering and calling them to the beatific vision. This is not all: the notion of original sin, without consideration of the definitions of the Council of Trent, is perverted, and at the same time the notion of sin in general as an offense against God, and likewise the concept of the satisfaction made by Christ for us. And there are those who contend that the doctrine of transsubstantiation, inasmuch as it is founded on an antiquated philosophical presence of Christ in the Most Holy Eucharist, is reduced to a kind of symbolism, so that the consecrated species are no more than efficacious signs of the spiritual presence of Christ, and of His intimate union with the faithful members in the mystical body.
Dz 2319 Some think that they are not bound by the doctrine proposed a few years ago in Our Encyclical Letter, bearing upon the sources of "revelation," which teaches that the mystical body of Christ and the Church are one and the same.* Some reduce to any empty formula the necessity of belonging to the true Church in order to attain eternal salvation. Others, finally, do injury to the reasonable nature of the "credibility" of the Christian faith.
3892 Dz 2320 It is well known how much the Church values human reason, in what is concerned with definitely demonstrating the existence of one personal God; and likewise with proving irrefutably from divine signs the foundations of the Christian faith itself; and, in like manner, with expressing rightly the law which the Creator has placed in the souls of men; and finally, with attaining some understanding, and this a most fruitful understanding, of the mysteries.* Yet reason will be able to fulfill this function only when it has been trained in the required manner; namely, when it has become imbued with that sound philosophy which has long stood out as a patrimony handed down from the earlier Christian ages, and so possesses the authority of an even higher order, because the magistetium of the Church has carefully weighed its principles and chief assertions, which were gradually made clear and defined by men of great genius, by the test of divine "revelation" itself. Indeed, this philosophy, recognized and accepted within the Church, protects the true and sincere value of human understanding, and constant metaphysical principles ---namely, of sufficient reason, causality, and finality---and, finally, the acquisition of certain and immutable truth.
3893 Dz 2321 To be sure in this philosophy many things are treated with which matters of faith and morals are neither directly nor indirectly concerned, and which, therefore, the Church entrusts to free discussion of learned men; but in regard to other matters, especially the principles and chief assertions which we mentioned above, the same freedom is not granted. In such essential questions, one may indeed clothe philosophy with a more fitting and richer dress, fortify it with more efficacious words, rid it of certain supports of scholars which are not fitting, and also cautiously enrich it with certain sound elements of progressive human study; but it is never right to subvert it, or to contaminate it with false principles, or to consider it a great but obsolete monument. For truth and its philosophic declaration cannot be changed from day to day, especially when it is a question of principles known to the human mind per se, or of those opinions which rest both on the wisdom of the ages, and on the consent and support of divine revelation. Whatever truth the human mind in its honest search will be able to discover, surely cannot be opposed to truth already acquired, since God, the highest Truth, created and directs the human intellect not that it may daily oppose new truths to those rightly acquired, but that by the removal of errors, which perchance have crept in, it can build truth upon truth in the same order and structure by which the very nature of things, from which truth is drawn, is perceived to have been constituted. Therefore, the Christian, whether philosopher or theologian, does not hastily and easily adopt every new thing thought up from day to day, but with the greatest care places it in the scale of justice, and weighs it, lest he lose or corrupt the truth already acquired, indeed with grave danger and harm to faith itself.
3894 Dz 2322 If these matters are thoroughly examined, it will be evident why the Church demands that future priests be instructed in the philosophic disciplines "according to the manner, doctrine, and principles of the Angelic Doctor,''* since it knows well from the experience of many ages that the method and system of Aquinas, whether in training beginners or investigating hidden truth, stand out with special prominence; moreover, that his doctrine is in harmony, as in a kind of symphony, with divine "revelation," and is most efficacious in laying safe foundations of faith, and also in collecting usefully and securely the fruits of sound progress.*
Dz 2323 For this reason it is to be exceedingly deplored that the philosophy accepted and recognized within the Church is today held in scorn by some; so much so that it is impudently renounced as antiquated in form, and rationalistic, as they say, in its process of thinking. For they insist that this philosophy of ours defends the false opinion that an absolutely true metaphysics can exist, while on the other hand they assert that things, especially the transcendent, cannot be expressed more aptly than by disparate doctrines, which complement each other, although, in a manner they are opposed to each other. So, they concede that the philosophy of our schools, with its clear description and solution of questions, with its accurate demarcation of notions and clear distinctions, can indeed be useful for a training in scholastic theology, well accommodated to the minds of men of the Middle Ages, but does not offer a system of philosophizing which corresponds with our modern culture and its needs. Then they raise the objection that an unchanging philosophy is nothing but a philosophy of immutable essences, while the modern mind must look to the "existence" of individual objects, and to life, which is always in a state of flux. While they despise this philosophy, they extol others, whether ancient or modern, whether of the peoples of the Orient or of the Occident, so that they seem to insinuate that any philosophy or belief with certain additions, if need be, as corrections or supplements, can be reconciled with Catholic dogma. No Catholic can doubt that this is quite false, especially since it involves those fictions which they call "immanence," or "idealism," or "materialism," whether historic or dialectic, or even "existentialism," whether professing atheism, or at least rejecting the value of metaphysical reasoning.
Dz 2324 And, finally, they find this fault with the traditional philosophy of our Schools, namely, that in the process of cognition it is concerned only with the intellect, and overlooks the function of the will, and of the affections of the mind. This certainly is not true. For never has Christian philosophy denied the usefulness and the efficacy of the good disposition of the entire mind for fully comprehending and embracing religious and moral truths; on the other hand, it has always taught that the lack of such dispositions can be the cause of the intellect becoming affected by disordered desires and an evil will, and of being so obscured that it does not see rightly. On the other hand the Common Doctor is of the opinion that the intellect can in some way perceive the higher goods that pertain to the moral order, whether natural or supernatural, since it experiences in the mind a kind of passionate "relationship" with these goods, whether natural, or added by the gift of grace; * and it is evident how much even such an obscure understanding can be an aid to the investigations of reason. Yet, it is one thing to recognize the force of the will for the disposition of the affections in aiding reason to acquire a more certain and firmer understanding of matters of morals; but these innovators make a different claim, namely, they assign to the faculties of desiring and coveting a kind of intuition, and that man, when he cannot through the process of reason decide with certainty what is to be accepted as true, turns to the will, by which he decides freely and chooses between opposite opinions, thus stupidly confusing the act of cognition and of the will.
Dz 2325 It is not strange that because of these new opinions two branches of philosophy are endangered, which by their nature are closely connected with the doctrine of faith, namely, theodicy and ethics. Indeed, some believe that the function of these disciplines is not to demonstrate anything certain about God or any other transcendental being, but rather to show that what faith teaches about a personal God and His precepts is in perfect harmony with the needs of life, and thus should be embraced by all, so that despair may be avoided and eternal salvation attained. Since all such opinions are openly opposed to the teachings of Our predecessors, Leo XIII and Pius X, they cannot be reconciled with the decrees of the Vatican Council. Surely, it would be superfluous to deplore these wanderings from the truth, if all, even in philosophical matters, would accept with due reverence the magisterium of the Church, whose duty it surely is not only to guard and interpret the deposit of truth revealed by God, but also to watch over these philosophical disciplines, lest Catholic dogma suffer any harm from incorrect opinions.
3895 Dz 2326 It remains for Us to say something on the questions which, although they have to do with the disciplines which are customarily called "positive," yet are more or less connected with the truths of Christian faith. Not a few insistently demand that the Catholic religion give as much consideration as possible to these disciplines. Surely, this is praiseworthy when it is a case of actually proven facts, but caution must be exercised when the question concerns "hypotheses," although in some manner based on human knowledge, in which hypotheses doctrine is discussed which is contained in the Sacred Scriptures or in "tradition." When such conjectural opinions are opposed directly or indirectly to the doctrine revealed by God, then their demand can in no way be admitted.
3896 Dz 2327 Wherefore, the magisterium of the Church does not forbid that the teaching of "evolution" be treated in accord with the present status of human disciplines and of theology, by investigations and disputations by learned men in both fields; insofar, of course, as the inquiry is concerned with the origin of the human body arising from already existing and living matter; and in such a way that the reasonings of both theories, namely of those in favor and of those in opposition, are weighed and judged with due seriousness, moderation, and temperance; and provided that all are ready to yield to the judgment of the Church, to which Christ has entrusted the duty of interpreting Sacred Scriptures authentically, and of preserving the dogmas of faith.*Yet some with daring boldness transgress this freedom of discussion, acting as if the origin of the human body from previously existing and living matter, were already certain and demonstrated from certain already discovered indications, and deduced by reasoning, and as if there were nothing in the sources of divine revelation which demands the greatest moderation and caution in this thinking.
3897 Dz 2328 When there is a question of another conjectural opinion, namely, of polygenism so-called, then the sons of the Church in no way enjoy such freedom. For the faithful in Christ cannot accept this view, which holds that either after Adam there existed men on this earth, who did not receive their origin by natural generation from him, the first parent of all; or that Adam signifies some kind of multitude of first parents; for it is by no means apparent how such an opinion can be reconciled with what the sources of revealed truth and the acts of the magisterium of the Church teaches about original sin, which proceeds from a sin truly committed by one Adam, and which is transmitted to all by generation, and exists in each one as his own.*
3898 Dz 2329 Just as in the biological and anthropological sciences, so also in the historical there are those who boldly transgress the limits and precautions established by the Church. And, We especially deplore a certain entirely too liberal manner of interpreting the historical books of the Old Testament, the supporters of which defend their case by reference without warrant to a letter given not long ago by the Pontifical Council on Biblical Affairs to the Archbishop of Paris.* This Letter plainly advises that the eleven first chapters of Genesis, although they do not conform properly with the methods of historical composition which distinguished Greek and Latin writers of past events, or the learned men of our age have used, nevertheless in a certain sense, to be examined and determined more fully by exegetes, are truly a kind of history; and that the same chapters, in simple and figurative speech suited to the mentality of a people of little culture, both recount the principal truths on which the attainment of our eternal salvation depends, and also the popular description of the origin of the human race and of the chosen people. But if the ancient sacred writers draw anything from popular narrations (which indeed can be conceded) it must never be forgotten that they did so assisted by the impulse of divine inspiration, by which in selecting and passing judgment on those documents, they were preserved free from all error.
3899 Dz 2330 Moreover, these matters which have been received into Sacred Literature from popular narrations are by no means to be identified with mythologies or other things of this kind, which proceed from undue imagination rather than from that zeal for truth and simplicity which so shines forth in the Sacred Books of the Old Testament that our sacred writers must evidently be said to excel the ancient profane writers.
Denzinger EN 3864