Is Theistic Evolution Truly Plausible?
by Thomas J. Centrella
“In the beginning, God created the heavens and the earth” (Gen 1:1).  He created the light, which He separated from the darkness; the waters, the sky, and the land; the plants and the trees; the sun, the moon, and the stars; the fish, the birds, and the animals (Gen 1:2-25). “And God saw that it was good” (Gen 1:25). Then, as the crowning jewel of His creation, “God created man in his own image, in the image of God he created him; male and female he created them” (Gen 1:27). God gave man dominion over all the other creatures that He created (Gen 1:28). “And God saw everything that he had made, and behold it was very good” (Gen 1:31).
In this article, I will carefully examine the origins of man and will discuss the plausibility of theistic evolution—specifically, the notion that man evolved from a lower animal species. I will show that in light of Sacred Scripture, the Magisterium of the Catholic Church, and sound reason, the theory of evolution, though perhaps remotely possible in a very restricted sense, is nevertheless not truly plausible.
The “theory of evolution” is actually a collection of several different theories, each with its own variations. As Father Brian Harrison points out,  each of these theories generally falls under one of six major categories. I will now present these categories in order, from the most radical to the least:
1) Total Atheistic or Pantheistic Evolution: This category claims that everything in the visible universe, including the totality of man, evolved exclusively through natural, material processes, either without the existence of God (atheistic) or as some kind of emanation from God (pantheistic).  Some versions even argue that God Himself has evolved.  This category also espouses polygenism, which is the belief that human beings descended from more than one human couple. 
2) Deistic Evolution: This category, like the previous one, contends that the entire visible universe, including the totality of man, evolved from matter. However, in this case, the existence of God is acknowledged as distinct from creation. Yet, God’s role would simply be to create the primeval elements and then let them naturally evolve into various life forms, including man (body and soul).  This category also espouses polygenism, and thus gives no credence to the historicity of Adam and Eve.
3) Polygenistic Theistic Evolution: This category admits a more direct role of the Creator in creation, but nevertheless accepts the premise that at least man’s body evolved from purely natural processes—even if perhaps under the guiding hand of Providence. This evolutionary process is known as natural transformism. The concept of natural transformism does not allow for any direct intervention by God after the alleged evolutionary process of life began. This category also accepts polygenism, thus treating Adam and Eve as either mythological fabrications or representatives of the first clan of human beings. Moreover, some of these theistic evolutionists may even argue that mans soul evolved. 
4) Monogenistic Theistic Evolution: Broad Natural Transformism. This form of evolutionary theory not only accepts that God’s Providence directed the evolution of man but also insists on (1) monogenism (the belief that the human race descended from only one human couple) and (2) the immediate creation of the soul by God (whether immediately after the human body was completely formed or just prior to that point, with some changes resulting from the infusion of the soul). But these theistic evolutionists still allow for natural transformism in the formation of the bodies of both Adam and Eve. 
5) Monogenistic Theistic Evolution: Natural Transformism for Adam Only. This is just like the previous category, except that it does not accept the notion that Eve’s body evolved from a lower animal species. The body of Adam, according to this form of evolutionary theory, evolved through purely natural processes, but supernatural intervention by God was involved in the formation of the body of Eve directly from the body of Adam. This category also affirms that God immediately created the souls of both Adam and Eve. 
6) Monogenistic Theistic Evolution: Special Transformism. Like the previous category, this form of evolutionary theory insists on (1) monogenism, (2) immediate creation of the soul, and (3) supernatural intervention by God in the creation of the body of Eve directly from the body of Adam. However, this more restrictive form of evolutionary theory does not allow for the natural transformism of the body of Adam. Instead, it proposes that the body of Adam developed through special transformism. Special transformism precludes the possibility of a lower animal species in any way being the parent of Adam, but it leaves open the possibility that God somehow used the “living matter” of a lower animal species to specially form man.
Now I will evaluate each of these categories. The first, Total Atheistic or Pantheistic Evolution, must, of course, be rejected immediately. St. Thomas Aquinas and others have proven in several ways, from reason alone, that God exists, and all of salvation history sings His praises.  Moreover, the Church has condemned all forms of pantheism, including any theories that claim that God has somehow evolved.  Eliminate Category 1.
The second category, Deistic Evolution, must be immediately rejected as well. In fact, it hardly differs at all from the first category.  It still attributes all but the very first spark of creation to purely natural processes, and the inherent Deism in this view has already been condemned by the Church.  As Vatican I affirms, “God protects and governs by His providence all things which He created…”  Thus, Category 2 is eliminated. 
The third category, Polygenistic Theistic Evolution, has several major problems as well. First, the Church has always affirmed the historicity of Adam and Eve. This is clear from the New Testament. For example, St. Paul confessed that “sin came into the world through one man, and so death spread to all men…” (Rom 5:12), and “death reigned from Adam to Moses…” (Rom 5:14). The historicity of our first parents is also supported by the writings of the Church Fathers. For example, St. Irenaeus, in about A.D. 180, affirmed:
Eve, however, was disobedient: and when yet a virgin, she did not obey. Just as she, who was then still a virgin although she had Adam for a husband…having become disobedient, was made the cause of death for herself and for the whole human race; so also Mary, betrothed to a man but nevertheless still a virgin, being obedient, was made the cause of salvation for herself and for the whole human race. 
Second, the Church has never accepted the notion of polygenism. In fact, Pope Pius XII explicitly rejected this false belief in his encyclical Humani Generis,  where he said in no uncertain terms:
When, however, there is a question of another conjectural opinion, namely polygenism, the children of the Church by no means enjoy such liberty. For the faithful cannot embrace that opinion which maintains either that after Adam there existed on this earth true men who did not take their origin through natural generation from him as from the first parent of all, or that Adam represents a certain number of first parents.12
12 Cfr Rom., V, 12-19; Conc. Trid., sess. V, can. 1-4.
In this same encyclical, Pope Pius XII rejected the false notion that the soul of man evolved, affirming that “the Catholic faith obliges us to hold that souls are immediately created by God.”  Therefore, on at least three counts, Category 3, Polygenistic Theistic Evolution, is eliminated.
That brings this analysis to the final three categories, which are all monogenistic forms of theistic evolution. The distinguishing feature of the fourth, and broadest, of these three categories is the notion that the body of Eve (along with that of Adam) evolved from a lower animal species. However, this assertion is in direct opposition to the constant teaching of the Church.
Genesis tells us that God placed Adam in the Garden of Eden and commanded him not to eat the fruit of the tree of the knowledge of good and evil. Such a command required that Adam already have a rational soul, for he had to be capable of freely choosing to obey this moral command.  Otherwise, he would not be culpable for disobeying it, as he later does (Gen 3:6), and God’s punishment for this disobedience (Gen 3:17-24) would have been unjust—which is impossible! Therefore, if one accepts any evolution of Adam’s body, it must be admitted that such evolution had already come to an end at this point, and that God had already created Adam’s soul (as recorded in Gen 2:7).
Moreover, it was after this command that God said, “It is not good that the man should be alone; I will make him a helper fit for him” (Gen 2:18). So God brought forth each of the animals that He created, and Adam gave them names (another action requiring a rational soul). Adam then realized what the Lord already knew: None of the animals was fit to be a helper for him (Gen 2:20). So, what did God do next—take one of those unfit animals and evolve it into a woman? Certainly not! The Lord did something far more profound: He caused the man to fall into a deep sleep, “and while he slept took one of his ribs and closed up its place with flesh; and the rib which the Lord God had taken from the man he made into a woman and brought her to the man” (Gen 2:21-22). Thus, Eve was created from the side of Adam by the direct intervention of Almighty God.
On this point, it is important to recall the typology that the Church sees in this historic event: Just as Eve was formed from the side of Adam, so the Church was sacramentally formed from the side of Christ when He was in the deep sleep of death on the Cross.  To deny that Eve was formed from the side of Adam is to implicitly deny that the Church was formed sacramentally from the side of Christ. These are pearls of the Faith, and they must not be left to swine. Hence, it is no surprise that the Pontifical Biblical Commission, while still an arm of the Magisterium,  listed “the formation of the first woman from the first man” as one of the literal and historical truths from Genesis that may not be called into question. 
Therefore, Category 4, Monogenistic Theistic Evolution: Broad Natural Transformism, which claims that the body of Eve evolved from a lower animal species, must be rejected. As Adam himself, the first man in all of creation, proclaimed: “This at last is bone of my bones and flesh of my flesh; she shall be called Woman, because she was taken out of Man” (Gen 2:23, emphasis mine).
Now that the creation of the first woman, Eve, taken directly from the side of Adam has been confirmed, I will turn to the issue of the creation of the first man, Adam. The last two categories of evolutionary theory, while admitting that the soul of Adam was created directly from God (as was that of Eve), hypothesize that the body of Adam (unlike that of Eve) evolved in some way from a lower animal species. These two categories, however, differ in the way in which they claim that this purported transformism took place. The less restrictive of the two, what I refer to as Monogenistic Theistic Evolution: Natural Transformism for Adam only, argues that Adam’s body evolved through natural transformism—that is, through a purely natural process from a lower animal species. However, this too has been ruled out by the Church, as I shall show.
Returning to Humani Generis, at first glance Pope Pius XII might appear to be leaving the door open to this form of evolutionary theory when he states:
For these reasons the Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter—for the Catholic faith obliges us to hold that souls are immediately created by God. 
However, notice the careful choice of words here: “as coming from pre-existent and living matter.” Pope Pius XII could just as easily have said “as evolving from a lower animal species,” which would have been more in line with an evolutionist’s way of putting it, but I believe he intentionally avoided stating it in such terms because the door was not—and is not—open to such an interpretation.  This is clearer when the text immediately following this quotation is carefully examined:
However this must be done in such a way that the reasons for both opinions, that is, those favorable and those unfavorable to evolution, be weighed and judged with the necessary seriousness, moderation and measure, and provided that all are prepared to submit to the judgment of the Church, to whom Christ has given the mission of interpreting authentically the Sacred Scriptures and of defending the dogmas of faith.11
11 Cfr. Allocut. Pont. To the members of the Academy of Science, November 30, 1941: A.A.S., vol. XXXIII, p. 506.
The footnote that Pope Pius XII includes here is significant. It is from an address that he himself gave to the Pontifical Academy of Sciences in 1941. Citing this footnote made it part of the official text of Humani Generis.  In this address, Pope Pius XII said: “Only from man could there come another man who would then call him father and ancestor; and the helpmate given by God to the first man came from man himself and is flesh from his flesh, made into a woman and called such because she came from man (Gen 2:23)” (emphasis mine). 
Consequently, when Pope Pius XII used the words “pre-existent living matter,” he was carefully distinguishing between natural and special transformation—leaving the door open to the latter (with a firm exhortation to exercise the utmost caution), but not to the former.  Likewise, Pope John Paul II, in his 1996 address to the Pontifical Academy of Sciences cited these very same words, “pre-existent living matter,” from Pope Pius XII, and thus did not open the already closed door to natural transformism. 
The care of both Pontiffs in using these precise words makes even more sense when one considers an earlier encyclical by Pope Leo XIII on marriage, in which he solemnly declared:
The true origin of marriage, venerable brothers, is well known to all. Though revilers of the Christian faith refuse to acknowledge the never-interrupted doctrine of the Church on this subject, and have long striven to destroy the testimony of all times, they have nevertheless failed… We record what is to all known, and cannot be doubted by any, that God, on the sixth day of creation, having made man from the slime of the earth, and having breathed into his face the breath of life, gave him a companion, whom He miraculously took from the side of Adam when he was locked in sleep. 
Besides obviously affirming the special formation of the body of Eve from the side of Adam, Pope Leo XIII was also clearly ruling out anything like natural transformism. When this very learned pope, who was surely aware of Darwin’s theory of evolution, mentioned the “revilers of the Christian faith,” he was likely including the proponents of that theory. It is very significant that he stated that it was well-known to all that God made man “on the sixth day of creation.” The doctrine on the origins of man (and thus of marriage) that was known to all the Catholic Bishops in the world in 1880 when he wrote this encyclical would have coincided precisely with a very strong statement about evolution made by the Catholic Bishops of Germany at the Provincial Council of Cologne just twenty years earlier—a statement that the Church has never repudiated: 
Our first parents were formed immediately by God. Therefore we declare that the opinion of those who do not fear to assert that this human being, man as regards his body, emerged finally from the spontaneous continuous change of imperfect nature to the more perfect, is clearly opposed to Sacred Scripture and the Faith. 
Moreover, by declaring that man was created on the sixth day, Pope Leo XIII was affirming that creation did in fact occur over the course of six historical days, as indicated by the plain sense of the words in Genesis 1, regardless of the actual time period represented by a “day.”  Now, since natural transformism presumes a purely natural process as the means by which the body of man evolved, the latest that any direct intervention by God could have occurred according to this theory would have been when God first created life on Earth—the third day.  However, as Father Brian Harrison points out, the words of Gen 2:7 “clearly indicate and record some sort of direct divine action upon matter as an efficient cause (either remote or proximate)”  of the body of Adam. Since, as Sacred Scripture states and Pope Leo XIII affirms, this direct intervention of God occurred on the sixth day, not the third day, natural transformism is ruled out. 
Moreover, the Pontifical Biblical Commission, in the same passage cited earlier, included “the special creation of man” as one of the literal, historical truths from Genesis that must be believed. 
Finally, in 557 A.D., Pope Pelagius I, in a profession of faith called Fides Pelagii, declared:
For I confess that all men from Adam, even to the consummation of the world, having been born and having died with Adam himself and his wife, who were not born of other parents, but were created, the one from the earth, the other [al.: altera], however, from the rib of man…” (emphasis mine). 
Thus, according to the teachings of the Catholic Church, no animal could have been the parent of Adam in any way. The notion of natural transformism must be rejected. Therefore, Category 5, Monogenistic Theistic Evolution: Natural Transformism for Adam only, is eliminated.
That leaves only one category of evolutionary theory not yet completely ruled out by the Church: Monogenistic Theistic Evolution: Special Transformism. This is the only form of evolutionary theory that the careful words of Pope Pius XII in Humani Generis (“pre-existent and living matter”) left open to further, but cautious, discussion.
Therefore, I will not argue that special transformism is impossible—at least from a theological standpoint.  However, I do contend that it is extremely problematic. Special transformism holds that the body of Adam evolved in some way from the living matter of a lower animal species, provided that this evolution would in no way make that species the parent of Adam. Some of the ways proposed for this process include the notion that God intervened directly to transform the union of a sperm and an egg of a lower animal species into the first human being,  or that God somehow formed Adam from some lower animal species similar to the way in which he formed Eve from the side of Adam. 
I see at least three major problems with this hypothesis. First, it is injurious to the teachings of Sacred Scripture and the Church about the special dignity of man, who was made in the image and likeness of God (Gen 1:27). Man was created in a state of holiness—clearly set apart from the rest of creation. The uniqueness of man is manifest in the language used to describe his special creation (Gen 1:26-27 and 2:7), in the immediate dominion he is given over all the animals (Gen 1:28) and his subsequent permission to eat them as food (Gen 9:2-3), and in God’s declaration that none of the animals are suitable to be a helper for him (Gen 2:18-20).
The second major problem with special transformism is that it contradicts the singular unity that exists between man and woman—a unity that is sacred and is the basis for marriage, as Christ Himself makes clear: “So they are no longer two but one” (Mt 19:3-6). Because Eve was taken from the side of Adam, there is a profound unity between man and woman in marriage. If, however, one conjectures that Adam was taken from the living matter of a beast, then a false tripartite unity is introduced between man, woman, and beast. This unseemly notion is entirely absent from any sense whatsoever of the entire canon of Scripture and from the entire Deposit of Faith.
The third major problem with special transformism is that it is illogical. Because so many of the tenets of neo-Darwinian evolution have been ruled out, what is left is a very disjointed process: God is seen guiding the evolution of an ape into some creature that seems to be headed toward looking like a man; then God intervenes and uses at least some of the living matter from this creature to form the body of Adam; next, God forms the body of Eve directly from the side of man; then He halts the evolutionary process so that no other human beings are produced that way. Wouldn’t it be more logical for God to bypass all those disjointed steps and form man’s body directly from the dust—precisely as the Sacred Scriptures record (Gen 2:7) and as God Himself reaffirms when He declares to Adam: “In the sweat of your face you shall eat bread till you return to the ground, for out of it you were taken” (Gen 3:19, emphasis mine)?
I see no reason to jump through so many hoops just to try to reconcile the Catholic Faith with a theory that was specifically designed to explain the origins of man without any reference to God. It seems to me that theistic evolutionists are in a corner: They must either abandon the teachings of the Church (God forbid!), abandon the theory of evolution, or else continue holding a very illogical position—one that neo-Darwinian evolutionists may very well scorn and laugh at, and that faithful, rational Catholics clearly ought to avoid.
So, is the theory of evolution possible? Yes, in a very restricted sense—for Adam only, but not for Eve or any other human being; for his body, but not for his soul; through a direct intervention of God from pre-existent living matter, but not through a purely natural process that would in any way make another creature his parent—it may be remotely possible. But is it truly plausible? Most assuredly, not. Therefore, I reject the theory of evolution.
Copyright 2007 Thomas J. Centrella
Thomas Centrella has a Bachelor of Science in Electrical Engineering (Magna Cum Laude) from Wilkes University and Master of Arts in Theological Studies (Summa Cum Laude, with Distinction) from the Notre Dame Graduate School of Christendom College. His research interests include Sacred Scripture, St. Thomas Aquinas, the Church Fathers, and Catholic principles of Morality and Law. Mr. Centrella has more than ten years of experience as a professional editor. He also has experience teaching religion and mathematics, and he is a veteran of the United States Air Force.
. All Scriptural quotes are from The Holy Bible, Revised Standard Version, Catholic Edition (San Francisco: Ignatius Press, 1965, 1966).
. Brian W. Harrison, “Did the Human Body Evolve Naturally? A Forgotten Papal Declaration,” Living Tradition, Jan.-Mar. 1998, nos. 73-74; http://www.rtforum.org/lt/lt73.html.
. John A. Hardon, S.J., The Catholic Catechism (New York: Bantam Doubleday Dell Publishing Group Inc., 1981), p. 91.
. Harrison, http://www.rtforum.org.
. Thomas Aquinas, Summa Theologica I, 2, 1-3, 2nd ed., trans. Fathers of the English Dominican Province, 1920, [online ed. by Kevin Knight, New Advent, 2003], http://www.newadvent.org/summa.
. The Vatican Council, Session III, Dogmatic Constitution Concerning the Catholic Faith, Apr. 24, 1870, Canons (of the Catholic Faith), Chapter I, Canons 1-5, in The Sources of Catholic Dogma (Enchiridion Symbolorum), 13th ed., Henry Denzinger, trans. Roy J. Deferrari (St, Louis: B. Herder Book Co., 1957), nos. 1801-1805.
. Harrison, http://www.rtforum.org.
. The Vatican Council, Session III, Apr. 24, 1870, Chapter I, in Denzinger, nos. 1782-1784.
. Ibid. Denzinger, no. 1784.
. Much more could be said to support my conclusion that the first two categories must be completely rejected. However, it is outside the scope of this article to treat exhaustively of these first two categories, which can so easily be refuted.
. St. Irenaeus, Against Heresies, c. 180 A.D., in The Faith of the Early Fathers, Vol. 1, trans. William A. Jurgens (Collegeville, Minn.: The Liturgical Press, 1970), no. 224.
. Pope Pius XII, Humani Generis (Some False Opinions which Threaten to Undermine Catholic Doctrine), Aug. 12, 1950, trans. N.C.W.C. (Boston: Pauline Books & Media), no. 37.
. Ibid. no. 36.
. Joseph M. Boyle, Jr., “Freedom, the Human Person, and Human Action,” in Principles of Catholic Moral Life, ed. William E. May (Chicago: Franciscan Herald Press, 1981), pp. 239.
. Catechism of the Catholic Church, trans. United States Catholic Conferences Inc. (New York: Catholic Book Publishing Co., 1994), no. 766.
. Prior to 1971, the Pontifical Biblical Commission was part of the Holy Office (what is today the Congregation for the Doctrine of the Faith), and thus an arm of the Magisterium. Pope St. Pius X, in his motu propio Præstantia Sacræ Scripturæ (EB 271), issued a grave warning declaring that all Catholics are bound by the Pontifical Biblical Commission’s decrees: “We find it necessary to declare and prescribe, as We do now declare and expressly prescribe, that all are bound in conscience to submit to the decisions of the Biblical Commission, which have been given in the past and which shall be given in the future, in the same way as to the Decrees which appertain to doctrine, issued by the Sacred Congregations and approved by the Sovereign Pontiff. Nor can they escape the stigma both of disobedience and temerity nor be free from grave guilt as often as they impugn these decisions either in word or writing; and this, over and above the scandal which they give and the sins of which they may be the cause before God by making other statements on these matters which are very frequently both rash and false.” In 1971, Pope Paul VI, in his motu proprio Sedula Cura, changed the status of the Pontifical Biblical Commission, so that it would no longer be an arm of the Magisterium. Thus, any PBC decrees issued after 1971 are not Magisterial (and hence not binding), but all PBC decrees issued prior to 1971 hold the weight of Magisterial Teaching.
. The Historical Character of the Earlier Chapters of Genesis, Question III, Pontifical Biblical Commission, June 30, 1909, in Denzinger, no. 2123.
. Humani Generis, no. 36.
. Harrison, http://www.rtforum.org.
. It is worthwhile to note that any footnotes included in an encyclical become part of what is officially being affirmed in that encyclical and, in fact, help explain what the text in that encyclical means (and what it does not mean). Thus, the authority of the footnoted material, in the context in which it is cited, is elevated to the authority of the encyclical where it is cited. (All this is likewise true for footnotes in ecumenical-council documents—for example, see the footnotes cited in Dei Verbum 11 affirming the total inerrancy of Sacred Scripture.)
. Pope Pius XII, To Plenary Session of the Pontifical Academy of Sciences, Nov. 30, 1941, (Irondale, Ala.: Eternal World Television Network); http://www.ewtn.com/library/PAPALDOC/P12PLEN.HTM, Internet, accessed July 24, 2005.
. Harrison, http://www.rtforum.org.
. Ibid. (Pope John Paul II said nothing in this address that changed the Church’s doctrine on evolution. His comments about the progress of science in no way endorsed evolution or opened any doors already closed. Moreover, such an address to the Pontifical Academy of Sciences does not hold any magisterial weight, since he was not exercising his papal authority but rather was simply giving a speech. In fact, the material that Pope Pius XII footnoted in Humani Generis from his address to the Academy of Science, which I discussed earlier, would also have fallen under this same category, but when he footnoted the material in his encyclical, he elevated the authority of this material to that of the encyclical, as I explained earlier.)
. Pope Leo XIII, Arcanum (On Christian Marriage), Feb. 10, 1880, no. 5, in The Papal Encyclicals 1878-1903, ed. Claudia Carlen IHM (Raleigh, N.C.: McGrath Publishing Co., 1981), p. 30.
. Harrison, http://www.rtforum.org.
. Provincial Council of Cologne, 1860, in Harrison, http://www.rtforum.org.
. The point is that each day represents a span of time, and the creation of man occurred during the sixth span of time.
. Harrison, http://www.rtforum.org.
. The Historical Character of the Earlier Chapters of Genesis, Question III, in Denzinger 2123.
. Pope Pelagius I, “The Last Things,” Fide Pelagii (from the letter “Humani Generis” to Childebert I), April 557, in Denzinger, no. 228a.
. It may very well be proven impossible from a scientific standpoint, as several authors have labored to show, but such an analysis is beyond the scope of this article.
. Harrison, http://www.rtforum.org.
. Hardon, pp. 92-93.