I've been thinking a lot lately about the position that the Catholic Church takes on the manner of God's creation of the cosmos in general, and specifically, about the creation of man. The Church does not definitively teach, or require the faithful to believe, any particular theory or concept about the creation of man or the creation of the world. As such, the faithful are free to believe any theory or concept that they believe in or reason to, provided that a charitable disposition is maintained toward those who do not believe likewise.
I myself, being devoted to the traditionally Roman Catholic adage of Faith and Reason, believe that the position that most embodies Reason, insofar as it is in step with the evidence we currently have, hold to an evolutionary perspective on creation. I believe that it is entirely possible that the Triune God did create all things and maintain them over time, ensuring in His Will that the process of evolution would proceed as He intended it to, being the causal basis for the constant change and movement that would have occurred given the evolutionary theory is accurate, as Thomistic philosophy would understand it. I am by no means adamant about this; the very nature of science is to change and expand in new directions as new evidence is found, and I am not attached to this theory as if it were guaranteed to be true, like so many secular or atheistic evolutionists. I also distinguish very carefully between Darwinistic Naturalism, the philosophy so often paired with the scientific theory of evolution, and the actual theory itself. One is a dismal philosophical view on the world that, causally and metaphysically speaking, defeats itself by reducing man down to an animal, and reducing the causality of all organic life down to inorganic life, which essentially renders life itself "all sound and fury, full of noise but signifying nothing," a tornado of matter that disorganizes as quickly as it organizes, temporally spinning up before being choked off by death, the only omnipotent value in this system. G.K. Chesterton spoke extensively on this exact philosophy in his book Orthodoxy, and he, too, carefully distinguishes between the scientific theory of a positive thing, such as a small rodent, turning into a positive thing, such as an ape, over time, with the philosophical worldview that so often is wedded to it, and he argues quite powerfully against the philosophy while insisting that the scientific theory as-such shouldn't trouble the most orthodox. The philosophy defeats science itself when carried to its logical end, since science is only as valuable as man himself, and since science also relies on fundamental axioms which Naturalist Materialist philosophy renders on dubious footing, when taken to its logical end. On the other hand, the scientific theory has a fair bit of evidence behind it, though it is extraordinarily controversial. It is worth noting as well that, as far as scientific theories go, it is dubitable that one can successfully apply the scientific method to it in order to gather incontrovertible, empirical evidence regarding it and exactly how it works. As such, it is vapid, nebulous, and vague to pinpoint exactly how it works, its origin, its forms, its limitations, and other essential scientific inquiries, such weaknesses being often covered up by rabid promotion of it in the arena of secular society, and the zealous and ardent marriage of the theory to the specific and narrow philosophy of Naturalistic Materialism. Even given all that, I cautiously accept it (as opposed to zealously promoting or promulgating it), for the time being, given that it is nearly universally held in some form for the physical development of organic life within the scientific arena. I am therefore a cautious theistic evolutionist, subscribing to Thomistic notions of causality regarding the origin, end, and being of all species of animals that have ever been, developed, and that exist today, being open to any and all evidence to the contrary. My mother believes in strict seven-day creationism, which gives me practice in being of the utmost charity and respect toward those fellow Christians with whom I do not fully agree; it also makes me grateful that the Roman Catholic Church does not mandate any one belief or teach any one specific concept regarding the creation of the cosmos by God, seeing as she is cautiously seeking to possibly come into the Catholic Church.
Having said all of that, I want to touch on one of the only specific and binding beliefs that Roman Catholics are bound to believe as necessary to the Catholic Faith, and I want to talk about why, according to Faith and Reason, it is necessary to hold this position as a Catholic. One of the only teachings that the Church binds on all Catholics regarding creation is that, essentially, there is a clear delineation between man and animal by reason of man's spiritual nature, His soul; that this spiritual nature did not evolve, but was specifically, willfully, metaphysically created and infused in man directly in his first origin; and finally, that there were two original parents of the human race, one male and one female, that represent the exact origin of humanity, and that Judeo-Christian Tradition and Catholic Sacred Tradition call Adam and Eve. Catholics are not free to believe that Adam and Eve are purely allegorical, and do not represent a historical fact, but rather just humanity in general, but they are free to believe that any amount of time has passed since the creation of these first two parents: 6,000 years, 60,000 years, 600,000 years, or 6,000,000 years. The time of their creation does not matter in the least, only the fact that they originally existed, their souls were created directly and immediately by God, they were given the choice to freely return the love to God which God, in His very nature, has extended to them and enlightened them by, and that they refused and thus cursed their posterity to live in a human dimension devoid of sanctifying grace and the direct, immediate presence of the Holy Spirit. Catholics are also free to interpret the first few chapters of Genesis allegorically, liturgically, spiritually, symbolically, as St. Augustine famously did in his writings, and are, on the other hand, free to interpret it absolutely literally as well. Let all men follow their consciences, their reasoning, and most importantly, their God in this matter.
Now that I've discussed the basic facts of the matter, let's look at precisely why the Roman Catholic Church takes this position on the creation of the soul of mankind immediately and directly by God. The reason is that there are profound implications to both human nature and the human person depending on his origin. The Church does not teach this immediate creation as a matter of necessity regarding the very physical existence of man; indeed, it is possible that the human body did evolve from the animal kingdom, in which case sin would partially be falling back into a baseness that we were never intended for. Rather, the Church teaches this formula for the creation of man for four main reasons that I can identify:
1) Because we, as the Roman Catholic Church, do not believe in a Deistic God. We do not believe in an Absentee Landlord who wound up the cosmos as a clock, set it to go, was its causality, and then left it alone and slumbered. We believe in a Divine Lover, a God whose very nature is Love, and whose very nature of Love by its very essence is diffusive in that it seeks to spill out of itself in an exitus, a going-forth of God's Love actively flowing to His creation, His creatios. We believe that this Love is so profoundly active, so real, that at a certain moment in time, which we identify absolutely with the creation of the first authentically human creatures; that it is so incredibly active in its pursuit of creation, that it directly involved itself in an utterly unique way in the creation of creatures with the Reason to know God and the Love to encounter Him, namely, human beings. We likewise believe that it is only ultimate Love that can satisfy the restless wanderings of the human soul, and that can give meaning and victory and hope to all human relationships of love which stand sentenced to death and destruction unless supported causally and spiritually by a Love that transcends death. It is essential that Roman Catholics believe this and live this worldview, because God is the Divine Spouse of His Creation (perfectly and wholly contained in its fulness in the Blessed Virgin Mary, the Spouse of the Triune God and the Body of Christ), and that He marries Himself to His creation, most absolutely in the Incarnation of God becoming physically and spiritually one with the Blessed Virgin Mary in the most profound way possible for Him to do so. This Divine Spouse of all the cosmos, and she who is greater and more expansive than the very cosmos, the Blessed Virgin Mary, desires to unite all to Himself in this Holy Marriage, and actively pursues us by His Grace to do so, desiring to incorporate us into the Immaculate Heart of Mary, so that we may share in her unimaginable union with the Sacred Heart of Jesus, true God and true man.
2) Because we, as the Roman Catholic Church, believe that the human person is sacred insofar as he possesses an immaterial soul that is the Image of God. This human soul sanctifies and hallows the human body by being joined to it in a union of which a closer cannot be imagined, and makes the whole man, body and soul, the Image of God, in a dignity that is only barely fathomable in the heavenly and unimaginable glorification of the Blessed Virgin Mary. Indeed, she, the preeminent human Image of her Son, is so far glorified in her position as the preeminent human being, and so far exalted above all creation, that her glory can only be understand in reference to God Himself, as she is infinitely less glorious than His eternal and infinite being. This is the destiny and intended place of mankind in the plan of God, and we therefore believe that the human person, body and soul, is sacred and that God has through him (most perfectly through the Blessed Virgin Mary) hallowed all of creation, the animals, the plants, and all nonliving matter, merely by the dignity of being of the same material, organic substance as man, and by the honor that man came materially from creation and that man's soul was joined to that material organic creation.
3) Because we, as the Roman Catholic Church, believe in the incarnation of God becoming man, and we believe that the creation of Adam and Eve directly and literally foreshadows and precedes the glorification and assumption of humanity, and in him all of creation, into the Divine Life of God through the Immaculate Conception of Mary and the Incarnation of God, Jesus Christ. In the same way, we believe that human suffering is explicable and causally linked, in a reasonable manner, to the fact that man was never intended to participate in suffering and evil, but was intended to transcend it and with him bring all creation into the realm of Divine Grace, Order, and Life. This resonates with our deepest soul because we know we were created for another world besides the one that we see around us. As C.S. Lewis so brilliantly points out, "If I find within myself a desire (an innate, human desire common to all human beings) that corresponds to no earthly thing, the most reasonable conclusion that I can come to is that I was made for another World."
4) Finally, because we, as the Roman Catholic Church, believe in the ordering of all existence metaphysically from the top down, actively from God down to man and through man to all creation. We do not subscribe to the philosophical notion that everything that man is can trace its causal relationship to reality only metaphysically down to lesser complexity, lesser greatness, and lesser being. We regard such a worldview as base, irrational, and ignominiously offensive to the axiomatic and inherent dignity of the human person. We believe that man is only at all explicable, and that includes all of his products including the sciences, reason, mathematics, the arts, the notion of independent and transcendent truth, morality, goodness, beauty, and perfection, if all of these things are properly metaphysical and spiritual and find their being in man's spiritual nature, His soul. Again, this spiritual, soulful reality of man is only explicable if that very soul finds its causality and being given to it from the metaphysically transcendent, since if it merely evolved from the metaphysically lower, and had no reference point in the Divine, it would not truly exist, but be an illusion. Furthermore, we as the Roman Catholic Church, both explicitly and implicitly, believe in a principle that the greater is the hallowed and sacred center of the less hallowed and sacred. This idea finds expression and echoes in the erecting of temples by the people of Israel, where there is an outer court, an inner court, a holy place, and a Most Holy Place, within the material walls of which the Presence of God dwells. The concept finds its greatest expression in the Incarnation of God Himself into the pure and immaculately holy human nature of the Blessed Virgin Mary. The Blessed Virgin Mary and the Incarnate God within her represent the preeminent fulfillment of all temples, and of this concept that the deeper you go within the cosmos, the more specific you narrow your focus, even down to the single human being of Jesus Christ, the closer you come to God until in this glorious fulfillment, God Himself comes down to meet you at the very singular and center of all the cosmos, Jesus Christ. This very Carmelite approach to all reality and all spirituality, that God and the holy dwell within the human person most profoundly and in the most hallowed manner in the cosmos, applies to all creation as well. Look around at the universe. What do we see when we peer into the farthest reaches of space and the very beginning of the universe, but bleak, nonliving, nonorganic, meaningless collisions of matter? It shows the glory of God and the immensity of God's nature, but it is given meaning by the fact that within it dwells the beautiful jewel of the Earth, existing in a perfection of location and being that is utterly uncanny, brilliant, and intelligent. Still, the earth is simply matter like all else, though beautiful and perfectly positioned. The Earth is given transcending meaning by the fact that within its confines is housed the more hallowed center of organic life, something utterly unique that has never been proven to exist anywhere else but on earth, something beautiful, something sacred. Still further we go, and still further life develops within the earth. Then, God creates something entirely new, something even more specific, a universe to itself and an entire world unto itself: the human person. You see this progression of the more hallowed and the more sacred further and deeper inward, until we get to the Image of God, the Imago Dei. The Image of God corresponds to the holy place in the temple of the Israelites, and is exceptionally holy. Through him all of creation is hallowed and given meaning, since he is the only creation literally capable of Reasoning about the cosmos, and elevating the cosmos to the Divine dignity and level of being a thought. All of this is wonderful, but there is one more layer to go, because none of this is causally supported unless at the center, the very core of humanity, God can be found. This is the Incarnation, the Holiest Place in the temple of all creation, absurdly beautiful concept that God is found more profoundly in the temple of His Human Nature that He Assumed to Himself, than in the farthest reaches of space and existence. The Blessed Virgin Mary is the purified and restored Imago Dei, the hallowed and sacred temple of God Himself, directly, physically, and spiritually. Jesus Christ, true God and true man, is Deus, God Himself, existing at the very heart of humanity; the core of all existence, the fountain of being, the Truth Himself. God is not to be found by searching the Heavens, He dwells within humanity, so profoundly that He assumed human nature to become man, and Man He remains for all eternity. This principle speaks volumes about human nature, for it speaks of man as being utterly unique and vastly more hallowed than any other aspect of creation. Through man, God hallowed all of the cosmos, and through the happy fault of Adam, used man and even man's free rebellion from the source of man's dignity and causality in God, to make human nature the instrument whereby the most profound glorification possible could take place: the physical and spiritual union of God with human nature, and through human nature, with the entire cosmos, in the one Person of Jesus Christ, the center of all existence.
Another beautiful conception of this Incarnational principle of hallowed and sacred lying at the center of the less hallowed and less sacred could be applies to the Church and the Sacred Scriptures. The Church is not as great as Sacred Scripture, but it was by the Church that the Sacred Scripture came into being by the overarching presence of the Holy Spirit, and it is the Church that is the caretaker, interpreter, and protecter of Sacred Scripture, and the two then are so intimately joined together that they represent the two natures of the Word of God: Sacred Tradition, and Sacred Scripture. In this way, the relationship of the Church to the Word of God in Scripture is a reflection of, and is roughly analogous to, the relationship of Mary to Jesus in the Incarnation, brought about by the overarching, hovering presence of the Holy Spirit. This makes perfect sense since the Blessed Virgin Mary is the Virgin made Church, the who is the fulness of the Church, and in whom we find our being and identity as the Church of God. If you search further and dig deeper, you will find this pattern at the heart of almost all Roman Catholic religion and spirituality, particularly profoundly in the role of the Blessed Virgin Mary in the lives of those here in the Church Militant here on Earth, and the fact that she is the Mediatrix of All Graces that we receive, and the God used her, as the Purified and Immaculate Imago Dei, to glorify all creation. Thus it is through her we go to Jesus Christ, since it is impossible to avoid such a journey: she is the very human nature Jesus Christ, and so if you believe in and seek to be joined to Jesus Christ, God and man, you will go through her regardless of whether you acknowledge her or ignore her like a cad and a louse. However, we as Roman Catholics show her veneration and respect her dignity profoundly, as is fitting and honorable and virtuous and pious, and we laud and hail her honor as the Mother of our God, and in doing so show honor to her Son, Jesus, Whose mother she she is; we also show that we recognize God assumed her, and her nature, into Himself and thus came to us no other way as our Divine Spouse. She is therefore, in the words of the Saints, the gate of Heaven and surest, safest path to Jesus Christ.
This is the Roman Catholic teaching, this is our belief, and this is our Faith. This is how we view the human person, and this is why we believe in the literalness of our first parents, Adam and Eve. It is not a blind faith, it is not a medieval holdover, it is not superstition, it is a rich tapestry that informs our understanding of the very nature of all reality, and the essence of the Observer and Thinker of all reality, the human person.