1. Introduction
As this Special Issue of
Religions testifies, the debate around the intelligibility of reality is still central to the field of science and theology. Must the intelligible nature of our universe be investigated philosophically and theologically? With regard to natural theology, should intelligibility be interpreted as a pointer toward something beyond nature? Some scholars would be inclined to consider it as a good starting point to argue for the existence and for some characteristics of a transcendent entity; for them, such intelligibility should be interpreted as the sign of a Mind. On the contrary, others would be more cautious and decline to endorse this stance. After all, intelligibility could simply be the natural feature of a universe beyond which absolutely nothing exists. In any case, that reality is intelligible, that it can be understood at least partially, is a statement that nowadays very few philosophers would deny. The enormous explanatory success of the empirical sciences is probably the best witness of it (
Davies 1998, pp. 65–68). But reality is not only intelligible; it is also mysterious (
Rosmini [1850] 1979, pp. 76–78). Intelligibility and mystery are not mutually exclusive. Indeed, contrary to an absurdity, a mystery is something whose depths never cease to be delved into, thus offering new insights to all those who decide to explore it. In our essay, we provide a brief analysis of some aspects of the interdisciplinary thought articulated by one explorer of our mysterious reality: Ernan McMullin. We will perform it with a specific aim in mind, namely, to highlight elements of his ideas on God and the God–world relation that he shares with a peculiar branch of European neo-scholasticism: neoclassical philosophy. This school of philosophy originated and flourished in Italy and is still present nowadays in the philosophical milieu of the Italian peninsula. Therefore, this neoclassical approach to philosophy should not be confused with its Anglo-American homonymous, which stands for process theism (
Dombrowski 2022), nor with other contemporary trends in analytic philosophy of religion labeled as neoclassical theism or neo-theism (for an overview of which see
Timpe 2013;
Feser 2022;
Echavarría 2023). In fact, the neoclassical tradition of thought that we will investigate is best understood as classical theism, as defined by
Fuqua and Koons (
2023). Our hope is that this two-pronged focus—on McMullin and Italian neoclassical philosophy—will help strengthen a classic epistemological scheme for the science–theology dialogue. This epistemological scheme, by conceiving philosophy as a mediator between theology and the sciences, has the potential to ground the intelligibility of the real and safeguard its inherently mysterious character.
2. Ernan McMullin: Augustine, God, and the Universe
Ernan McMullin (1924–2011) was a well-known historian and philosopher of science and also a prominent figure in the dialogue between the sciences, philosophy, and Christian theology (
Hess and Allen 2008, pp. 134–37). His theory of a “consonance” between the sciences and religion via the mediation of a rigorous epistemology is one of the most stimulating intellectual proposals in this field. If asked to pinpoint in a nutshell the main elements of McMullin’s legacy for science and theology studies, we would list the following: his appreciation of Augustine’s philosophical and theological reflection; his suspicion of the widespread use of natural theology in order to (try to) bridge the empirical sciences and theology; his acquaintance with modern and contemporary sciences, and their methodologies (among the studies on McMullin, see
Allen 2006,
2012;
Stoeger 2013;
Barzaghi and Corcó 2015).
Theologian Paul Allen, one of the best-known interpreters of McMullin’s thought, highlights a possible connection between the first and second aspects of his interdisciplinary reflection, stating that “My impression of McMullin’s repeated reliance upon Augustine is that he is reminding us of the limits of moving too quickly or seamlessly from nature to God. Such a philosophy or natural theology is not credible or sufficiently wise, and for this reason, Augustine remains deeply relevant to contemporary discussions of theology and science” (
Allen 2013, p. 16). In an essay on
McMullin’s Augustinian Settlement, Allen recalls again the lack of an explicit natural theology in McMullin and underscores the pertinence of this absence to his Augustinian approach: “Alas, McMullin did not propose metaphysical or detailed theological schemes. Thus, he did not formulate a natural theology apart from the odd, teasing suggestion. His satisfaction with Augustine’s epistemological categories and his Platonized sparseness triumphed in his mind over the complexities of Thomism” (
Allen 2012, p. 342).
Another very typical and very classic Augustinian aspect of McMullin’s thought is the way in which he conceives of God and the God–world relation. God, the omnipotent Creator of the entire universe, stands outside space and time. His act of ontological creation—interpreted as primary causality—is seen as perfectly compatible with the secondary causes of nature. In this theological scenario, nature, its laws, and time and space themselves are God’s own creations. Therefore, “from God’s atemporal standpoint, the Creation is a bringing to be of the universe from its first moment to its last in a single act” (
McMullin 2011, p. 294). It should be noted that, as McMullin himself makes clear in one of his most known papers on science and theology, these conceptions of God and the God–world relation were embraced by Thomas Aquinas as well (
McMullin 2013, p. 356). His appreciation of Augustine and Aquinas on such issues invites us to reconsider, from a theoretical standpoint, McMullin’s relations with some branches of European neo-scholasticism of the twentieth century, which tried to reactualize these, as well as other aspects of Augustine’s and Aquinas’s metaphysics.
3. Louvain and Milan
A striking historical occurrence renders our investigation more intriguing. Indeed, McMullin earned his doctorate in philosophy from the Catholic University of Louvain, Belgium, in 1954, with a thesis in the philosophy of science on
The Principle of Uncertainty (
Sloan 2012;
Sayre 2014). The Catholic University of Louvain, thanks to the Institut Supérieur de Philosophie—founded and promoted by Cardinal Désiré Mercier in the wake of Pope Leo XIII’s encyclical
Aeterni Patris of 1879—was one of the major European hubs of scholastic philosophy in the nineteenth and twentieth centuries. In his brief reconstruction of the history of the Institut Supérieur in the twentieth century, Jean Ladrière highlights some of the pillars that grounded the intellectual work there ever since the institute’s foundation. Among them, we can mention the centrality of the historico-critical study of the major philosophers of the past, with a special focus on Aquinas; the conviction of the necessity for philosophy to take into due account the progress of the empirical sciences; the importance of a nuanced articulation of the relationship between philosophy—conceived as the work of human reason alone, unaided by God’s revelation—and Christian faith and theology; the search for a constant, constructive dialogue with the broader contemporary intellectual milieu (
Ladrière 1994, p. 626; see also
Paul 2018).
Another well-known academic center that, following Leo XIII’s advice in
Aeterni Patris, strongly promoted the renaissance and reactualization of scholastic philosophy for the twentieth century was the Catholic University of the Sacred Heart in Milan, founded in 1921 by the Franciscan friar Agostino Gemelli (
Molinaro 1994;
Forment 2003;
Tarquini 2022). Its faculty of philosophy shared the ideals of Mercier’s institute. Amato Masnovo (1880–1955), faculty member and professor of medieval philosophy and metaphysics, was the leader of the school of philosophy that originated there (
Neva 2002;
Pagani 2012a). Masnovo admired the intellectual enterprise of his Belgian colleagues and offered his contribution to the dialogue with several philosophical exchanges, as well as with some papers in the journal of the institute (
Pietroforte 2005;
Gilbert 2008). The schools of Louvain and Milan—notwithstanding their differences and specificities—developed lines of inquiry whose first aim was elaborating a rigorous and simplified philosophy: one that would be able to dismiss the obsolete elements of classic philosophy and medieval scholasticism and, at the same time, to safeguard all those ancient and medieval achievements in philosophy that, in their eyes, should be considered as perennially valid.
Strong echoes of this very attitude can be found inside the metaphysical–theological ruminations of Ernan McMullin. As already anticipated, a glaring example of it is his Augustinian endorsement of the classic notion of God’s atemporality, which allows him to solve some thorny interdisciplinary issues related to the challenges posed by evolutionary contingency and the non-directionality of biological evolution to a theistic worldview (
McMullin 2013;
Stoeger 2013;
Barzaghi and Corcó 2015).
The Augustinian and Thomistic conceptions of God and of the God–world relation embraced by McMullin in his interdisciplinary writings were also tenets of Masnovo’s philosophy, which originated a so-called “neoclassical” branch of neo-scholasticism at the Catholic University. The articulation of a neoclassical metaphysics is one of the major contributions of Masnovo’s best-known disciple, Gustavo Bontadini (1903–1990), as well as of some of Bontadini’s disciples in contemporary philosophy, such as Carmelo Vigna and Paolo Pagani (on Bontadini see
Grion 2012;
Pagani 2016; on Vigna see
Pagani 2012b;
Benso 2017, pp. 63–72;
Bettineschi et al. 2022; on Pagani see
Barzaghi 2018, pp. 837–40;
Tarquini 2022, pp. 175–83, 347–49). A neoclassical philosophy is rigorous and essential in spirit. Its aims are to build a fundamental theory of knowledge as well as a stable path to God that is metaphysical in essence. For neoclassical philosophy, the latter is intimately related to the former. Indeed, according to neoclassical philosophers, human intentionality aims at the world, not at some representations of it. Therefore, our knowing of the world, a process interpreted as the way in which the world manifests itself, reveals some ontological constants that allow us to investigate the reasons why the world exists—an investigation that culminates in a metaphysical, metempirical inference to the ground of being. In addition, the neoclassical philosopher will also analyze several other natural theological arguments inside classic as well as contemporary literature, thus detecting aspects of them that, from a neoclassical standpoint, turn out to be problematic (
Bontadini 1995b;
Gnemmi 1972).
4. An Augustinian Philosophical Path to God
Creatio ex nihilo—creation out of nothing—is the typical way in which the Christian theological tradition conceives the act of God’s ontological creation of the universe. McMullin devotes the last section of an essay on the early history of this concept to the legacy of the Saint of Hippo (
McMullin 2010). In it, he recalls Augustine’s philosophical encounter with the Plotinian ideas of God and His relation to the world and then proceeds to compare and contrast Plotinus’s and Augustine’s explanations of that relation: emanation for the former and creation out of nothing for the latter.
Where Plotinus had made all else emanate from the One, Augustine had all else be the work of the One as Creator. Where Plotinus had the emanations gradually descend to the level of a matter that as non-being is over against the One and ultimately the source of evil, Augustine argued that the realities created by the Good could only themselves be good. The creative act on God’s part can only be ex nihilo; there is nothing that could serve as material for it. To suppose otherwise would be to make God no longer the One.
McMullin’s comment about Augustine’s theoretical advancement over Plotinus is illuminating because it provides general guidelines on how to consider both God’s atemporality and His act of creation in an interdisciplinary context: “The warrant for the doctrine of creation
ex nihilo was now the testimony of philosophical reason as well as of the biblical tradition” (
McMullin 2010, p. 21). According to this interpretation, the Augustinian position stems from theological rumination on the revealed datum and from philosophical reflection. This would imply that, for Augustine, it is possible to delve into the mystery of God’s attributes, as well as of His act of creation, not only in a theological but also in a philosophical—i.e., purely rational—way. This is one of the ideas that Masnovo also considered crucial for understanding Augustine’s intellectual legacy correctly. Indeed, for the Italian philosopher, some exquisitely philosophical elements can be pinpointed inside—and extracted from—Augustine’s theological reflection. Among them is a path to God in nuce that, if analyzed, turns out to be a forerunner of Aquinas’s first way.
In
L’ascesa a Dio in Sant’Agostino (
The Ascent to God in Saint Augustine) as well as in S
. Agostino o S. Tomaso? (
S. Augustine or S. Thomas?), Masnovo revisits a specific season of Augustine’s reflection: the one prior to his conversion (
Masnovo 1942a,
1942b). In other words, he evokes a key distinction between the “first” and the “second” Augustine: if the former philosophized outside faith, the latter did it inside faith (
Bontadini 1995a). More specifically, Masnovo, in these two essays, decides to focus on those aspects of Augustine’s philosophical theology that he elaborated on in his philosophical youth and that can also be detected in his theological maturity. Indeed, in
Confessions XI.iv.6, interpreting the very first passages of the book of Genesis, Augustine writes: “See, heaven and earth exist, they cry aloud that they are made, for they suffer change and variation” (
Augustine 1991, p. 224). Masnovo invites us to consider and appreciate the continuity between this reflection, extracted from the “second Augustine” and a previous one, from
Confessions VII.i.1, which reveals some philosophical convictions of the young Augustine prior to his encounter with Neoplatonism, that reads: “With all my heart I believed you to be incorruptible, immune from injury, and unchangeable” (
Augustine 1991, p. 111). Their theoretical relation is quite straightforward. On the one hand, God should be conceived as completely subtracted from becoming. On the other, the world’s becoming is precisely that very sign of contingency that testifies to—or presupposes—a creator God subtracted from becoming (
Masnovo 1942b, pp. 137–38). Masnovo, thus, connects these quotes from the
Confessions to Aquinas’s natural theology. Indeed, in the aforementioned passage of Book XI, Chapter 4, he detects the deployment of a very specific kind of cause: efficient causality. In doing so, Augustine would, thus, be anticipating Thomas’s formulation of the ancient and medieval principle that reads “omne quod movetur ab alio movetur”: whatever moves is moved by something else. Scholars have debated over the best way of interpreting and, therefore, translating the first movetur, which in Latin expresses both the passive and the reflexive forms (
Wippel 2000, p. 414 and references therein). According to Masnovo, the philosophical meaning of that sentence should be rendered as follows: “Whatever becomes (because it becomes) does not have in itself the sufficient reason of its own becoming” (
Masnovo [1936] 2011, p. 45, our translation; see also
Masnovo 1942b, p. 148). This way of reading the sentence signals that, for him, “omne quod movetur ab alio movetur” must be interpreted as an articulation of the principle of causality. Revoking the quote from Book XI, Chapter 4 of the
Confessions, Masnovo, thus, states that “It is not possible to consider that ‘facta sunt, mutantur enim’ [they are created, for they change] without, at the same time, thinking about the efficacy of the principle of causality for Saint Augustine and precisely as the hidden but real gluten which solders the antecedent ‘mutantur’ [they change] to the consequent ‘facta sunt’ [they are created]” (
Masnovo 1942b, p. 142, our translation).
5. A Neoclassical Path to God
The centrality of Augustine’s metaphysical thought for both McMullin and Masnovo invites us to reflect on the role that neoclassical metaphysics could have in contemporary science and theology. In this context, a neoclassical philosophy would be engaged in some of the tasks usually undertaken by neoclassical philosophers: to (try to) articulate a rigorous and essential path to God—thus integrating McMullin’s reflection, which lacks it— and to scrutinize with its conceptual toolkit other natural theological arguments, thus rejecting those that, according to neoclassical standards, would appear to be problematic.
In this sense,
McMullin’s (
1988) essay
Natural Science and Belief in a Creator seems to hint at the essential path to God conceived, in other contexts, by Masnovo and his disciples. Commenting on the attempts by some contemporary philosophers—among whom towers Étienne Gilson—to resuscitate Aquinas’s five ways, he describes briefly a new form of natural theology that was envisioned in those years. In any case, it must be noted that in these passages McMullin seems to be quite circumspect also on those renewed approaches to the Transcendent, thus confirming Allen’s statements on his skeptical attitude towards the proofs of God.
Gilson and many other modern commentators on the “Ways” argue that they have to be extracted from the matrix of Greek natural philosophy and formulated in metaphysical language, utilizing a broadened existential notion of efficient cause that leads to the affirmation of a First Cause and not just an Aristotelian Mover or Platonic Demiurge. In this way, the weaknesses of the original formulation can (they believe) be overcome. The “Ways” then reduce, in a sense, to a single proof, one that begins from some observed general feature of the physical world, such as motion or efficient causal relationship, and infers to the necessity of a First Cause for the existence of such a feature. Gilson is at some pains to present the proofs, even the first Way, as being “independent of any scientific hypothesis as to the structure of the universe”. Whether in the end such a transformation is possible, while retaining the logical structure of the proofs, may be questioned. And whether the resultant argument ought be characterized as “natural theology” is also dubious. It would seem that an argument which relies on features like contingency and finitude, imputed to the physical universe as a whole on the basis of conceptual considerations, is more properly labelled “metaphysical”.
The elements to be retained from this passage for our first panoramic characterization of a neoclassical approach to natural theology are the following. Firstly, the older formulations of the paths to God should be extracted from the pre-Galilean natural philosophy in which they were embedded. Therefore, they should be reformulated in an explicitly, exquisitely metaphysical jargon. This would imply that they should be reduced to an essential single path, which would take as its starting point one very specific feature of the universe, namely, “motion”. The outcome would, thus, be a notion of God that describes Him not as an intermediate Demiurge or a Prime Mover but rather as the responsible for the very existence of the universe—in other words, as a full Creator.
The neoclassical path to God, articulated by some contemporary Italian philosophers in light of Masnovo’s teachings, considers motion as synonymous with becoming. The argument runs as follows. Everything in our experience moves; everything changes. This means that everything is becoming: not only physical stuff but also mental entities, such as our own thoughts, now thinking A and then B. This very becoming of both our universe and our experience is, for neoclassical philosophers, a sign of creatureliness. Why? Because it would be absurd—it would imply a contradiction—to conceive of the entirety of reality as becoming (
Bontadini 1996). Let us call the entirety of reality “the absolute”. The absolute is that above which nothing exists and, therefore, that which has in itself its own sufficient reasons for existence. Given the existence of anything, the absolute exists necessarily: it will be either that very thing that exists or something else (
Vigna 2015). For neoclassical philosophy, absolutizing our becoming universe would imply a contradiction. A becoming absolute would, thus, be a non-absolute absolute. In what would this contradiction consist? In a becoming absolute, every new being or every new configuration of being that enters the cosmic scenario would be continuously springing from non-being; and vice versa, all those beings or all those configurations of being that ceaselessly leave the cosmic scenario would be continuously disappearing into nothingness. In other words, in such a scenario, we would be continuously witnessing the impossible origination of being from non-being and the equally impossible disappearance of being into non-being. This would imply that, inside our universe, the impossible identification of being and non-being would be taking place continuously (for an in-depth analysis of this aspect of the neoclassical argument, see
Barzaghi 2018).
From this, neoclassical philosophers conclude that the real absolute cannot be in becoming. Given that time is the “measure” of our “changing universe” (
McMullin 2011, p. 294), the real absolute must be conceived as standing outside space and time. This is one of the metaphysical convictions on God’s nature that McMullin shares with neoclassical philosophers: as them, he fully embraces Augustine’s and Thomas’s positions. Indeed, inside his interdisciplinary essays, while defending the idea of God’s atemporality, he constantly refers to the Saint of Hippo.
Augustine was particularly interested in clarifying the Creator’s relationship with time. Time is a feature of the created world just as is space and is brought to be, therefore, with that world. Temporality involves limitation: the past resides with us only in fading memory; the future exists for us only in our expectations. The Creator is not eternal in the sense of an unending succession—which would be a form of time. Rather, the Creator is eternal in the sense of atemporal, a Being to whom time-predicates of any sort simply do not apply.
A neoclassical path to God also articulates philosophically the concept of creation. The relationship between our becoming/changing universe and this newly discovered absolute, which does not become, must for them be conceived as one of free creation of the former by the latter, i.e., a radical dependency in being of the former on the latter. This conclusion is drawn in order to avoid a possible twofold contradiction, which would consist of (a) conceiving the absolute as the system of the non-becoming being and the becoming universe, thus reintroducing becoming inside the absolute, and (b) conceiving the absolute as forced to create, thus introducing a sort of necessity inside the absolute, i.e., a dependency of the non-becoming absolute on the becoming universe (
Vigna 2015;
Pagani 2012b, pp. 91–102,
2016,
2023b). The absolute discovered in this way is a philosophical—metaphysical—characterization of God, and His relationship with the universe is a philosophical—metaphysical—description of the act of free creation on the part of God.
This metaphysical formulation of the classic proof that takes as its starting point the becoming nature of our universe is also worthy of attention for the method it adopts. Indeed, as highlighted previously, each of its logical passages is demonstrated by resorting to reductio ad absurdum. The argument tries to show how the statements that contradict each step of the proof would be self-contradictory. In this way, the truth of the statement that this becoming universe is not the absolute would be demonstrated.
As already noted, the application of this method to other contemporary natural theological arguments has the potential to pinpoint some of their possible theoretical problems. Indeed, if tested with the procedure of the reductio, many natural theological arguments in science and theology would turn out to be inconclusive precisely because the statements that contradict their theses are not in themselves self-contradictory. That would imply that the hypothetical absurdity that should follow, for the specific proof under focus to be valid, would not be such; i.e., it would not be an absurdity at all. By way of example, let us briefly consider design arguments/teleological arguments (following
Ratzsch and Koperski 2023, we read the two expressions as synonymous) in their specific form that focuses on living beings to try to infer the existence of a God, thus articulating a biological design argument. The hypothesis of the hypothetical absurdity of absolutizing a nature in which unthoughtful teleologies emerge; in other words, the hypothesis according to which unthoughtful teleologies cannot be explained without any kind of reference—either scientific or philosophical—to a supernatural Designer, or again, the hypothesis according to which unthoughtful teleologies cannot be explained in a fully naturalistic fashion, and, therefore, they should be interpreted as signs of creatureliness, does not pass neoclassical muster. This hypothesis does not have the strength to deny its contradictory statement, according to which it is not absurd, it is not impossible for an unintelligent, unconscious nature to produce teleological behaviors. In this sense, Darwin’s elegant naturalistic explanation of biological teleology confirms the neoclassical critique and represents the final nail in the coffin of biological design arguments (
Ayala 1970;
Lennox and Kampourakis 2013;
Jantzen 2014, pp. 136–52).
1 Therefore, the introduction of this methodology in science and theology could integrate McMullin’s Augustinism, articulating a proof whose inner logic is Thomistic as well as Augustinian in essence.
6. Conclusions: Grounding Intelligibility, Safeguarding Mystery
Neoclassical philosophy is, thus, a good candidate for providing a rigorous philosophical foundation to the science–theology dialogue. Its procedure for formulating a metaphysical path to God from the becoming of the universe can enter into constructive dialogue with natural theological reasoning as found in interdisciplinary areas, helping it become more essential. Such an enterprise, if successful, would contribute to the philosophical grounding of the intelligibility of our cosmos, a feature that has charmed those who have explored it ever since the birth of the philosophical and scientific enterprises. For neoclassical philosophers, intelligibility per se would not be a viable starting point for inferring God. They would not be interested in articulating design/teleological arguments. They would rather prefer to reason on becoming, which, for them, represents the most fundamental springboard to reach God. In our paper, we have recalled the outcome of a neoclassical metaphysical path. The very origin, the ground of our becoming, intelligible universe is an omnipotent, atemporal, free Creator. For neoclassical philosophy, then, human reason can discover the creator God at the end of a metaphysical argument over the ultimate meaning of everything. In any case, this exquisitely philosophical approach to the Divine should not be seen as hybristic. The philosopher who decides to investigate the nature and attributes of God with a neoclassical outlook is well aware that a rational approach to the Transcendent is not inevitably doomed to be rationalistic. On the contrary, that approach safeguards the other characteristic of our universe, which appears in the title of this paper: its mystery. Indeed, the aim of neoclassical philosophers is not to say the final word on God, thus denying all the other, possibly richer depictions of Him provided by different approaches, either from inside or outside philosophy. Rather, they try to establish what reason can confidently prove over the issue of God’s existence, attributes, and actions. In doing so, they let the mystery be a mystery, and they safeguard mystery, making room for all the other investigations that respect it (
Pagani 2023a). In this scenario, the empirical sciences will keep delving into our mysterious universe, ceaselessly providing new insights into its workings. As for the Christian tradition, theological reason will have nothing to fear from a neoclassical approach to the Transcendent. The theologian will find in the neoclassical philosopher a fellow traveler and ally willing to offer rational support to some of theology’s most crucial convictions, namely, that God exists and that He creates the cosmos. In return, the theologian will tell her philosophical friend about another mysterious territory, above but not contrary to human reason: the one opened by a faith that freely embraces God’s self-revelation.