Question: Is the Thomistic account of creation compatible with the account of the natural world given by the contemporary empirical sciences?
Answered by Brandon Zimmerman (Good Shepherd Seminary, Papua New Guinea)
a. 1 – What is the meaning of the question?
In order to answer this question, we must clarify what is meant by “contemporary science” and by “the Thomistic account of creation.” Contemporary empirical science is the systematic attempt to explain the physical universe in terms of material and efficient causes, with the causes themselves being reduced to matter and energy. Causality is ideally explained through mathematical models that can be empirically verified. Thus for instance, biology seeks to explain the activities of living things in terms of chemical interactions, the distinction of living things through differences in DNA, and the origin of the various species through naturally occurring variation in the genetic make-up of offspring (mutations) combined with environmental factors (natural selection). However, to claim that such explanations are the only valid explanations and that the interactions of matter and energy are all there is is to step beyond science into philosophy by embracing a philosophical position such as materialism or naturalism. Such philosophical claims cannot themselves be proved by empirical science since concepts like truth, evidence, and model are not themselves explainable through scientific methods. The philosophical position that the empirical sciences have a monopoly on the truth is entirely inconsistent with Thomas’s thought (and with the thought of most major philosophers), since Thomas holds that metaphysics, the unrestricted study of being (including immaterial and intentional being), has a greater explanatory power than the sciences that only study one part or aspect of being (such as being as visible [optics]; or living being [biology]). Metaphysics also studies and clarifies the basic explanatory concepts that the partial sciences take for granted. Furthermore, Thomas accepts theology (sacra doctrina), the rational study of God’s self-revelation to man, mediated by Scripture and Church tradition, as the highest science, and thus of the greatest possible explanatory power.
Therefore, the question will be understood as asking whether Thomas’s metaphysical and theological accounts of creation are compatible with the explanations that contemporary science gives of the physical world, such as evolution and the Big Bang. Throughout his writings, Thomas distinguishes between the essential doctrine of creation which is knowable through both natural reason and special revelation and was (he claims) in fact achieved by Thomas’s philosophical predecessors and the details about how the world came to be which are only known through special revelation and are studied by theology. Let us summarize and analyze in turn Thomas’s metaphysical (i.e., philosophical) and theological accounts of creation, and his understanding of the relationships between metaphysics, theology, and natural science.
Thomas himself did not understand science in the manner that we do today, though our empirical sciences roughly correspond to what he calls “intermediate sciences,” which apply mathematical principles to the explanation of natural things. Such sciences straddle natural science (scientia naturalis) and mathematics, which, with metaphysics, are the branches of speculative science. For Thomas himself, natural science is the conceptual study of the physical world and, following Aristotle, is divided into the general study of motion and being as movable (physics), and then the application of those principles to different kinds of changes and changing bodies in the universe, such as the heavens, the four elements, meteorology, and the generation of plants and animals. In his commentaries on Aristotle’s writings and some of opuscula, Thomas shows a keen interest in natural science, but only a general acquaintance with the intermediate sciences of his time. Today, we must admit that insofar as Thomas is mostly a follower of the Aristotelian commentary tradition, (Thomas generally seeks to show how Aristotle’s general positions are in harmony with later science, especially Ptolemy), much of his applied natural science is incompatible with contemporary science and is mostly of historical interest only. However, Thomas’s understanding of the relations between, on one hand, sciences that restrict themselves to the study of the physical world and worldly causes and, on the other hand, metaphysics and theology, which are universal in scope, remain relevant to contemporary questions about the compatibility of scientific, philosophical, and theological thinking. In what follows, when I mention natural science or physics, I generally mean the level of explanatory discourse that the empirical sciences concern today; while metaphysics roughly corresponds to general philosophical discourse.
I must also note the limitations of my study. The question of the creation of human souls is quite complicated and will not be treated here. The questions of whether Thomas’s division of the sciences can be mapped on to our contemporary divisions and whether Thomas’s physics and general understanding of creaturely causality are compatible with contemporary science are beyond the scope of my response.
a. 2 – Is Thomas Aquinas’s philosophical account of creation compatible with the account of the natural world given by the contemporary empirical sciences?
In his earliest explanation of creation, Aquinas argues “not only does faith hold that there is creation but reason also demonstrates it,” and he explains in detail the doctrine of creation that “philosophers have held.” For Aquinas, to demonstrate in metaphysics that there is an absolutely first principle that causes the existence of all things is to prove that there is a creator. We see in the Sentences Commentary 184.108.40.206–2, Summa Contra Gentiles II.15–16, and Summa Theologiae I, q. 44–45 that Thomas first establishes a first cause of universal being, and then identifies the action of such a cause as creation. Complementarily, Thomas says in De Potentia q. 3, a.5, ST I, q.44, a. 2, and On Separate Substances 9.48–49 that to establish a cause of universal being is to discover creation, which is the distinct mode of causality proper to God. Aquinas’s proofs for a creator are usually only dependent upon a general analysis of how beings exist, and thus do not presuppose any particular explanation of the material world. In fact, they do not even presuppose a distinct metaphysics, since Aquinas offers proofs based on Platonic, Aristotelian, Avicennian, and Neoplatonic principles.
As the cause of the existence of all being, the Creator is not a member of the universe of created beings, but entirely transcends the manner in which creatures exists. Thomas denies that any term can be predicated of God and creatures univocally, arguing that God exists and acts in a manner more perfect than we can comprehend. Thomas thus often tries to prevent us from attributing creaturely modes of being and acting to God by emphasizing what God is not; for example, God is not analyzable into parts, time and space do not apply to him, his being and power have no limits. This same negative strategy is found throughout Thomas’s philosophical accounts of creation in which Thomas insists that creation is not a change. All creaturely action consists in changing something that already exists and thus involves succession and a preexistent subject: first the subject was this way, it is affected by an agent, and now it is that way. However, “creation is the production of a thing in its entire substance, without presupposing anything, uncreated or created.” Only God, who simply is being, in contrast to creatures which are beings limited in some way, can cause existence in an absolute manner. God’s causality extends to every aspect of the creature and thus presupposes no preexistent thing to serve as a subject or instrument. The creature comes to be at once, without undergoing a process, since there is nothing to be processed. According to Thomas, one cannot even speak meaningfully of a time before creation, since God is outside time, and time as the measure of motion only began with the universe. Without creation, there is only God—no time, space, or potentiality (except for the power of God); via creation, all beings are. Thus, God’s creative activity does not take place within the universe, but is what causes the universe to be. Creation is thus very different from the spatiotemporal changes that creatures effect.
Additionally, since the entirety of being is caused by God, without God’s activity, creatures would cease to exist. Thus creation is not a once and done act by God; but all creatures continue to depend on God’s creative act for all that they are. “If the created thing is left to itself, it would not exist.” According to Thomas, the conservation and creation of creatures are the same divine act, just as that I cause my image in the mirror and that that image remains in the mirror are simply caused by my presence, and not by my presence and another action. Now for some philosophers, such as Al-Ghazali and Malebranche, the doctrine of creation=conservation is used to support occasionalism, the theory that God is the only agent and that created things are in fact powerless. For example, when a fire sets some paper ablaze, it is really God that causes the paper to light and to burn, not the fire. The concurrence of natural things is simply the occasion for God’s action. Throughout his work, Thomas attacks occasionalism for making the actions of all things purposeless, for being contrary to our empirical experience of the world, and for diminishing the power of God by making God unable to create things with real power and real goodness. While all things depend on God for their being, as beings they act and are acted upon according to their natural potencies. Following Aristotle’s cosmology, Aquinas even contends that some natural beings, such as pure matter and the heavens, are necessary, meaning that in themselves they have no potency for corruption, and thus can be neither generated nor destroyed by natural forces. Aquinas thus argues for a certain amount of autonomy for nature. While no creature can cause the being of another absolutely, once creatures have been established, the coming to be and perishing of terrestrial creatures can be explained via the interaction of natural agents. Regarding its order and not its existence, the natural order preserves itself, such that Aquinas will describe certain beings as causing and preserving the existence of others. On the other hand, God is intimately involved in the providential ordering of all things (which Aquinas generally treats as a philosophical topic), such that nothing happens contrary to the divine will. Yet, Aquinas famously argues that God’s agency and creaturely agency are so radically different that there is no competition between them. God works in every agent without changing the nature of the agent’s act; such that God accomplishes his purposes through contingent, voluntary, and necessary causes without depriving them of their contingency, freedom, or necessity. For God’s will is the source of the different forms of causality. It is not the case that God does one part of the action and the agent another part such that their contributions could conflict, rather the action is “wholly done by both.” We can gain some insight into this teaching by considering human creativity. When an author writes a book, everything in the book is brought into being by the author, and yet on the level of the story, things happen due to contingent, necessary, and voluntary agents. Therefore, for Thomas, it would make no more sense to ask whether something is caused by a natural process or by God than it would to ask if King Duncan was killed by Macbeth or by Shakespeare.
In sum, Thomas argues that creatio ex nihilo, meaning that God, presupposing nothing, immediately causes the entire being of everything and providentially holds all thing in existence, can and has been established through philosophy. This metaphysical account of creation and the empirical sciences are in principle complementary. Thomas defends the real agency and intelligibility of nature. While modern philosophers, such as René Descartes and Francis Bacon, attacked the idea of teleology or purpose in nature on the grounds that we would have to know the mind of God to discover nature’s purposes, Thomas generally explains teleology as meaning that all beings cause determinate effects which reveal the nature of the agent to the human observer. Furthermore, since the universe is the product of an intelligence and since the natures of material things are the proper objects of the human mind, humans should be able to understand the workings of nature. Thomas’s account of providence generally leads him away from “God of the gaps” arguments, i.e. arguments that try to show that natural processes are insufficient to account for some aspect of the world, such that God’s intervention must be posited as the cause. In fact, from the limited viewpoint of natural science, the investigation of changeable, perceptible being, the axiom that nothing comes from nothing holds true for all natural processes and created agents. Beings neither annihilate nor create one another; they only change one another. For Thomas, the question of the ultimate origins of the universe (and thus God and creation) is outside of the scope of natural science, and is reserved for metaphysics. Even then, Thomas says that whether the universe had a temporal beginning or has existed forever cannot be decided by metaphysics or physics, for either is possible and the present world would be the same either way. At best, physics would suggest that the world is eternal, while metaphysics would reveal that it is possible that God could have made a temporally bounded world. While contemporary science is today able to model the universe’s past in a way Thomas could not have conceived, the current lack of consensus about whether the Big Bang is an absolute beginning of the universe or not would generally support Thomas’s philosophical agnosticism regarding the world’s temporal being. Describing the world purely in terms of physical causes with mathematical modeling is, in principle, completely compatible with Thomas’s thought, as long as one does not, from that limited viewpoint, make judgments on topics that belong properly to metaphysics, such as providence and creation.
However, a clear incompatibility between Thomas’s metaphysical account of creation and contemporary science is that Thomas follows Aristotle’s practice of linking metaphysics to astronomy, by arguing that the supposedly unchanging movements of the heavens can only be accounted for by positing immaterial movers. Thus, for example, one of Thomas’s arguments for God’s existence is based on the need for a mover of the heavens. In a similar vein, Thomas’s main example of how creatures conserve each other in being is Aristotle’s theory that the heavenly bodies are responsible for substantial change on earth, to which Thomas adds that separate substances (angels and ultimately God) are themselves responsible for the movements of the heavens. Therefore, the details of Thomas’s account of the conservation of the natural world must be radically revised, and it must be admitted that in regard to celestial motion, Thomas does fall into seeing God’s action as filling in gaps in nature.
Regarding possible worlds or alternate universes, Thomas argues that God could have made a different cosmic order but has unchangeably chosen the present one. He seems to think that God would only will to create a universe with a full spectrum of beings: inanimate, plant, animal, rational, and spiritual. Though such a universe could be temporally unbounded (no temporal beginning or end), Thomas seems to hold that the universe must be spatial finite. Thomas argues that an actually infinite magnitude is in itself unknowable, (since all knowledge is based on form and the infinite lacks the form of a number), and thereby is incompatible with the world being caused by an intelligence. Thomas argues that there can only be one actually existing universe at any time, with one Earth at its center, though his arguments are mostly taken from Aristotelian cosmology. Modern speculative cosmology is well beyond the horizons of his Thirteenth Century thought.
a. 3 – Is Thomas Aquinas’s theological account of creation compatible with the account of the natural world given by the contemporary empirical sciences?
Thomas argues throughout his works that the above account of creation, while revealed in Scripture, is also provable through philosophy. As mentioned above, philosophy and science cannot establish whether the universe has a temporal beginning or is eternal, since both are possible in reference to themselves and to God’s power. We can only know what God has willed regarding the duration of the world if God himself tells us. Therefore the main contribution that theology makes to our understanding of creation is that the world has a temporal beginning and the details of the world’s initial formation (though Thomas also says that revelation helps us to understand that creation is a free choice by God and that all things image the Trinity). Hence, any scientific theory that claimed that the universe must be eternal would be inconsistent with Thomas’s theological account of creation, though Thomas also resists all attempts to prove the temporal beginning of the world through philosophy.
Thomas argues, from a theological vantage point, that in theory there can be no conflict between the truth that we know from Scripture and the truth we know through natural reason. As he explains most fully in his Commentary on Boethius’s De Trinitate, God is the ultimate cause of both our intellectual power and of our faith in Scripture, as well as of Scripture itself. If what we establish as true through natural reason were at odds with what we believe to be true through faith, then God would be guilty of giving us a faulty intellect or a false revelation, both of which are impossible. Therefore, it is impossible that philosophical and scientific truths are contrary to the truths of faith.
But what do we do if the content of faith seems to be at odds with the truth discovered by natural reason? Thomas’s typical reply is that we should look to see in what manner natural reason has erred. It belong to theology both to judge the conclusions of the natural sciences and philosophy, and also to show on their own terms what error they have made, including showing that the position which is apparently at odds with the faith is only probable and not necessary. For it is only erroneous science and philosophy that can conflict with the faith, not scientific and philosophical truth. Aquinas thus enjoins theologians to engage in science and philosophy and to actively seek to resolve apparent conflicts.
When setting forth his interpretation of Genesis’s creation story, Aquinas admits that an apparent conflict between science and faith can also be due to an erroneous interpretation of Scripture. While Aquinas says that we must hold true to the truth of Scripture, we must not import our own erroneous views into our Biblical interpretations and then cling to human error as if it were revealed truth. Therefore, Aquinas says that one should entertain various interpretations of the same passage as being possible, while being ready to abandon any one interpretation “if it be proved with certainty to be false; lest Holy Scripture be exposed to the ridicule of the unbelievers, and obstacles be placed to their believing.” In theory, then, Thomas holds that any interpretation of Scripture that conflicts with established scientific truth is to be rejected as not what Scripture means to say, but as human error.
In actually, Aquinas presents two general interpretations of Genesis as possible. First, that Genesis intends to explain to us the step-by-step formation of the cosmos over the course of six 24-hour days. Aquinas strives to harmonize this rather literal interpretation with the science and philosophy of his day, believing that Genesis means to explain “how God has constituted the nature of his creatures,” such that difficulties in the account cannot be solved by appealing to God’s miraculous power, but be reconcilable with our scientific knowledge of nature. The obscurity of Genesis’ details is at least partially due to the fact that Moses was condescending to the level of ignorant people and thus explained the universe in terms of how it immediately appears to humans, thereby omitting scientific and metaphysical details. Thomas is thus dedicated to filling in the gaps by interpreting Genesis as describing the formation of an Aristotelian-Ptolemaic universe, which is divided into a terrestrial realm composed of the four elements and a heavenly realm composed of ether, which is itself divided into various regions and planetary spheres. Thomas rejects certain interpretations of the details of the creation story on the ground that contemporary science and metaphysics judge them to be impossible. For instance, he says that not even the authority of Genesis 1:2 can force one to think that prime matter once existed without form, since, according to Thomas, matter can only exist in union with form. Likewise, Thomas rejects readings of Genesis 1:6–8 that would place actual water in the heavens as being physically impossible, while insisting that this detail, like all the other details, must correspond to some feature of the physical universe. At times, Thomas is even willing to consider physical theories at variance with his own. For instance, he notes that the Platonic view that the heavens and earth are made up of the same kind of elements is better able to account for the formation of the heavenly bodies on the fourth day than his own Aristotelian view that the heavens are incorruptible.
Secondly, Aquinas also always respectfully presents, in parallel to the first interpretive strategy, Augustine’s interpretation from his Literal Commentary on Genesis that the seven days indicate the natural order of dependence and natural priority of the parts of creation, and not actual steps in the universe’s formation. According to Augustine, the first three “days” indicate the basic hierarchy of created beings: light and darkness=angels and demons, water and firmament=the heavens, earth and plants=terrestrial being; “day” four is creation of corporeal light; and days five and six, as well as the plants of day three, indicate that God endowed the universe with the power to produce plant and animal life, not the actual production of such life. The various forms of life in fact only developed after the initial creation event, in accordance with God’s providence. Aquinas notes Biblical support for Augustine’s interpretation and that certain difficulties in trying to understand Genesis both literally and scientifically are resolved by Augustine’s understanding that the matter and potentialities of the universe were made at once, and served as the basis for their later propagation of living things. However, Aquinas seems to think that the first interpretation, that God created all or most species during the six days and then providentially oversaw their reproduction and preservation, fits better with the idea of God resting on the seventh day. In either case, Aquinas affirms that it is fitting that “God gave his creatures at first an imperfect state, so that by degrees they might proceed from nothingness to perfection.” He also says that Augustine is correct that nature is, as it were, seeded with “active and passive virtues which are the causes of natural generation and movements.” Indeed, Aquinas sometimes depicts change not as so much as a natural agent imparting a new form to a subject, but as enabling what already existed in potency in a certain combination of matter to emerge. Aquinas even grants that through the interactions of these powers, new species of animals may arise, (although he principally has spontaneous generation from putrefying matter in mind).
Thus, in principle, Aquinas is committed to harmonizing Scripture with truth that has been established by natural reason, and he admits that apparent conflicts can be due to errors in science or philosophy or errors in Scripture interpretation. However, his dedication to this harmony led him to interpret Genesis so as to reconcile it with the science of his day, such that most of the fruits of his first interpretative method are not compatible with contemporary empirical science and must be rejected. At the same time, if Thomas Aquinas were alive today, his exegetical principles and goals would lead him to seek to harmonize Genesis with our contemporary science. If then biology has established the development and diversification of species took place gradually through genetic mutations controlled by natural selection, and if cosmology has established that the universe has formed gradually from an initial disordered unity of all matter and energy, then presumably Aquinas would want to show that Genesis 1–2 need not conflict with and can be reconciled with evolution and the Big Bang, just as he had sought to reconcile Genesis with Ptolemaic astronomy. While this would mean abandoning his first interpretative strategy of a literal six-day creation, Aquinas has left himself at least two possible routes of escape. The first would be to radicalize his often repeated remark that Genesis was written for uneducated people who had not moved beyond the world of immediate sense experience, into the judgment that Genesis does not intend to give a scientific account of the universe’s formation at all. Extrapolating from Aquinas’s willingness to grant that the creation myth in Plato’s Timaeus need not be taken literally but is meant to express the dependence of all things on God, perhaps Aquinas would be open to understand Genesis as using cosmological models of the ancient Near East to express the truth of creation in a manner acceptable to ancient peoples, without Scripture endorsing the details of those models as historical fact. Complementary, the second solution would be to embrace and thoroughly develop Augustine’s nonliteral interpretation of Genesis, by understanding God as providentially moving the universe from imperfect disorder to more perfect order through the natural processes of galactic and planetary formation and biological evolution; thereby fully integrating Aquinas’s metaphysical account of creation with his Scripture exegesis, while freeing both of Aristotle’s natural science.
Such a revision of Thomas’ account of creation would not be as radical as one might think. Following Aristotle’s natural science, De Potentia q. 4, a. 1, ad 20 speculates that God may have separated the waters from the dry earth through the natural effect of the heavenly bodies on water and that plants were formed through the influence of the heavens on the dry land. Thus, Thomas is open to explaining the formation of the world via God working through the interactions of natural forces. Furthermore, Thomas himself says that it belongs to the substance of the faith to know that the world began by creation, “but the manner and the order according to which creation took place concerns the faith only incidentally, in so far as it has been recorded in Scripture,” hence the various and divergent interpretations of the details of Genesis by the Church Fathers. By making a new harmony of Scripture with contemporary science, contemporary Thomists would be safeguarding anew the substance of Thomas’s account of creation, as revealed in Scripture and established in philosophy, by renovating its accidents relating to the empirical sciences.
 Proemium to Commentary on the Metaphysics, Commentary on Boethius’s De Trinitate q. 5, a. 4.
 See n.1 and Commentary on Boethius De Trinitate q. 5, a. 1, ad 9
 Summa Theologiae I, q. 1, aa. 5–6 (henceforth ST); Summa Contra Gentiles II.4.4 (henceforth SCG).
 Commentary on Boethius’s De Trinitate q. 5, a. 3, ad 5–7.
 See Commentary on De Caelo, introduction and lectio1; Commentary on Meteorology, lectio 1; Commentary on Generation and Corruption, introduction; Commentary on Physics, lectio 1, 1–4.
 See Commentary on De Sensu, introduction. Thomas has brief works on the movement of the heart and on how elements mix together to form new substances.
 For instance, Commentary on De Caelo, 15.433–40
 Sentences Commentary bk II, d. 1, q. 1, a. 2.
 De Potentia q. 3, a. 5 and ST I, q. 44, a. 1. Cf. Prologue to the Commentary on the Gospel of John, 2-6, especially 4 and Commentary on Liber De Causis, proposition 3.
 ST I, q. 3, a. 4, ad. 2 and a. 8; De Potentia q. 7, a. 2, ad 4–6.
 ST I, q. 4, a. 2; q. 13, aa. 2 and 5.
 De Potentia q. 7, a.5, ad 13. ST I, q. 3, preface.
 Sentences Commentary bk II, d. 1, q. 1, a. 2; ST I, q. 45, a. 2, ad 2 and a. 3; SCG II.17; De Potentia q. 3, a. 2.
 ST I, q. 65, a. 3. Cf. Sentences Commentary bk II, d. 1, q. 1, a. 2.
 ST I, q. 45, a. 5 and De Potentia q. 3, aa. 1 and 4.
 ST I, q. 10, aa. 1–4; Commentary on On Interpretation, lectio 14.20.
 De Potentia q. 3, a. 2.
 ST I, q. 46, a. 3.
 Sentences Commentary bk II, d. 1, q. 1, a. 2. Cf. De Potentia q. 3, a. 7, ad 7 and ST I, q. 44, a. 1.
 ST I, q. 104, a. 1, ad 3.
 ST I, q. 105, a. 5 and q. 103, a. 6 and De Potentia q. 3, a. 7.
 ST I, q. 104, a. 1.obj and ad 1 and a. 4; ST I, q. 46, a. 1, ad 2 and 3; De Potentia q. 5, a. 3, ad 12 and a. 5, ad 9.
 ST I, q. 65, a. 4.
 ST I, q. 104, aa. 1–2 and q. 105, a. 3; De Potentia q. 5, a. 1, ad 7.
 ST I, q. 22, a. 2; q. 103, a. 5 and 7.
 ST I, q. 22, a. 4; q. 103, aa. 6 and 8; q. 105, aa. 3–5; and q. 116, a. 1.
 Commentary on On Interpretation, 14.22.
 SCG III.70.8. See n. 20.
 ST I, q. 44, a. 4 and II, q. 1, a. 2.
 ST I, q. 12, a. 4 and q. 84, a. 7.
 Cf. William E. Carroll “Creation, Evolution, and Thomas Aquinas.” Revue des Questions Scientifiques 171 (2000): 319–47. For example, some Twentieth Century theists argue that life in general, or sensation, or intelligence cannot arise through natural processes, but can only be caused by God’s intervention. An analogy in epistemology to “God of the gaps” thinking is that humans can only grasp universal truth through a direct participation in the divine intellect (a position known as illuminationism). By contrast, Aquinas argues that humans have the natural power to discover the truth, though this natural power, like all power, is ultimately dependent on God.
 SCG II.16.14; De Potentia q. 3, a. 1, ad 1; ST I, q. 45, a. 2, ad 2.
 Commentary on Boethius’ De Trinitate q. 5, a. 2, ad 7. ST I, q. 44, a. 2; De Potentia q. 3, a. 5. See n. 24.
 De Potentia q. 3, a. 17; ST q. 46, a 1 and ad 2–3, and a. 2; Commentary on the Sentences 220.127.116.11.
 Commentary on Boethius’ De Trinitate, q. 5, a. 2, ad 6. As discussed above, such explanations belong to the intermediate sciences.
 Commentary on Boethius’ De Trinitate q. 5, a. 1, ad 9. Cf. SCG II.91.9; ST I, q. 110, a. 1, including ad 2 and 3.
 On Separate Substances 2.8–9 and 13–14; Sentences Commentary 18.104.22.168, third argument for a first principle. In contrast to the first way of ST I, q. 2, a. 3, these presentations of the argument from motion identify the motion that needs to be accounted for as the motion of the heavens and not motion in general.
 De Potentia q. 5, aa. 1–3; ST I, q. 65, a. 4, including ad 2; q. 104, aa. 1–2; q. 110, a. 3; q. 115, a. 3, including ad 2.
 De Potentia q. 3, a. 16; ST q. 19, a. 3 and a. 7, ad 4; De Veritate q. 23, a. 4.
 ST I, q. 23, a. 5; q. 47, aa. 1–2.
 Thomas is not entirely consistent on whether God could create something that is actually infinite, but ST I, q. 7, a. 4 and q. 25, a. 2, ad 2 and Quodlibet XII, q. 2, a. 2 answer in the negative.
 ST I, q. 47, a. 3.
 De Potentia q. 3, a. 14 and On the Eternity of the World.
 Sentences Commentary 22.214.171.124
 ST I, q. 32, a. 1, ad 3 and q. 45, a. 7.
 Notes 43 and 34 above.
 Commentary on Boethius’ De Trinitate q. 2, a. 3.
 ST I, q. 1, a. 6, ad 2.
 Commentary on Boethius’ De Trinitate q.2, a. 3, including ad 7–8. Cf. SCG I.7.7 and II.3–4.
 ST I, q. 68, a. 1. See also De Potentia q. 4, a. 1. Thomas is adapting these points from Augustine, Literal Commentary on Genesis I, 18, 19, 21 and Confessions V.3.4–5.8 and XII.17.24–25.35.
 ST I, q. 74, a. 3, ad 6–7.
 ST I, q. 68, a. 2, ad 1. The quotation is Thomas’s quotation of Augustine, Literal Commentary on Genesis II.1.
 ST I, q. 68, a. 3; q. 67, a. 4; q. 70, a. 1, ad 3.
 Cf ST I, q. 32, a. 1, ad 2 for Thomas accepting Ptolemy because it harmonizes the sensible appearances of the heavens with Aristotle’s astronomical principles.
 ST I, q. 68, a. 4.
 De Potentia q. 4, a. 1, ad 14.
 ST I, q. 68, a. 2; De Potentia q. 4, a. 1, ad 5.
 ST I, q. 70, a. 1, ad. 1; cf. q. 68, a. 1.
 ST I, q. 66, a. 1; q. 69, aa. 1–2; q. 74, a. 2
 ST I, q. 73.
 De Potentia q. 4, a.1, ad 8. Cf. ST I, q. 70, a. 2, ad 5.
 ST I, q. 115, a. 2. The seminales rationes.
 ST I, q. 73, a. 1, ad 3.
 Commentary on De Caelo, I.22.228, 23.231 and 233, and 29.277 and 283.
 ST I, q. 1, a. 10, ad 2–3. Here Thomas says that when Scripture uses analogical or figurative language, the literal meaning is what is figured, not the figure itself. Thomas says in ST I, q. 102, a. 1 that whenever Scripture states something as historical fact, the text is to be taken literally and not figuratively, however, Thomas’s willingness to present and consider Augustine’s figurative interpretation of Genesis 1 indicates that he does not understand the creation story as necessarily stating historical facts.
 Sentences Commentary II.12.1.2. Quoted in William Carroll, “Thomas Aquinas on Science, Sacra Doctrina, and Creation,” in Nature and Scripture in the Abrahamic Religions: Up to 1700, vol. 1, ed. Jitse M. van der Meer and Scott Mandelbrote (Leiden: Brill, 2008), 219–48, 243.