Engaging Jeffrey Koperski’s decretalism: is occasionalism really avoidable?

Abstract

This article critically evaluates Jeffrey Koperski’s decretalism, which presents the laws of nature as divine decrees functioning as constraints rather than dynamic forces. Building on his work, we explore whether his model successfully avoids the implications of occasionalism, as he claims. By analysing his latest publications, we first reconstruct Koperski’s argument and then present three key objections. These include (1) issues related to scientific realism, (2) the principle of simplicity, and (3) the reduction of Koperski’s model to occasionalism. We argue that despite his attempts to distinguish his framework, Koperski’s model ultimately collapses into occasionalism due to the continuous divine sustenance required for natural processes. By engaging with recent developments in metaphysical and scientific debates, this article highlights the limitations of Koperski’s decretalism.

Introduction

Philosophical debates in two key areas have seen notable advancements in recent years. The first centres on the constraint view of the laws of nature, which regards these laws not as actively governing events but as imposing limits on the ongoing physical processes. The second area focuses on decretalism, which interprets the laws or regularities of nature as expressions of divine will. Although these two areas have traditionally developed independently, Jeffrey Koperski has proposed an innovative model of divine action that integrates insights from both. Koperski embraces decretalism, portraying laws of nature as divine decrees that function as constraints rather than as dynamic causes driving the entire evolution of physical processes. His primary motivation for adopting the constraint view of laws of nature is avoiding occasionalism, a position he sees as a pitfall that earlier proponents of decretalism fell into.

In what follows, we first trace the historical development of Koperski’s ideas, particularly in his discussions with Robert Larmer, and clarify how his model of divine action fits within the framework of decretalism and the constraint-view of laws of nature. Second, we analyse Koperski’s model of decretalism and his arguments against occasionalism, reconstructing his reasoning in detail. Third, we compare Koperski’s version of decretalism with occasionalism and examine whether his model genuinely avoids the implications of occasionalism or ultimately collapses into it. We argue that occasionalism provides a more robust framework than Koperski’s divine action model, and that his decretalism is unstable, ultimately converging with occasionalism. To support this claim, we present three central objections. The first concerns Koperski’s stance on scientific realism, the second compares his model with occasionalism in terms of simplicity and explanatory power, and the third addresses the internal consistency of his approach.

The intellectual background of Koperski’s decretalism

First, let us provide a broader overview of the constraint approach to the laws of nature and decretalism, then position Koperski’s ideas within this larger framework.

Eddy Keming Chen and Shelly Goldstein present a model known as ‘Minimal Primitivism’ (MinP), where the laws of physics are viewed as fundamental constraints governing the universe. In this view, laws are primitive, irreducible facts about the world that do not require deeper metaphysical explanations. Rather than dynamically producing events, these laws limit the range of physical possibilities across all spacetime without reference to the flow of time or underlying causes. While it is not explicitly stated that Minimal Primitivism rejects the causal power of laws, the model suggests that laws act more as boundary-setters than as dynamic causes. For Chen and Goldstein, laws function as primitive constraints, operating without the need for divine agency or dynamic production (Chen and Goldstein 2022). Although this view lacks any explicit theistic connotations, Chen acknowledges its potential extension to a theistic interpretation. He references the perspective of Hildebrand and Metcalf (2021), who argue that laws of nature could be created by a supernatural being. Chen notes, ‘Their account is presumably as flexible as MinP, since they do not impose restrictions on the forms that laws can take’ (Chen 2024, 26).

Emily Adlam also offers a constraint-view of the laws of nature through her model of global constraints. Adlam argues that laws of nature do not function as local, time-bound mechanisms but instead operate as overarching principles that structure the entire spacetime continuum. In her view, laws are global constraints that apply to the totality of spacetime, shaping the behaviour of the universe as a whole, rather than merely dictating specific events at particular points in time. She does not commit to the idea that laws of nature are primitive. This contrasts with Chen and Goldstein’s Minimal Primitivism, which treats laws as primitive constraints that shape possibilities locally across spacetime without direct involvement in temporal dynamics. While both views reject the need for dynamic production or causal powers in laws, Adlam emphasizes the holistic, interconnected nature of these constraints across spacetime, offering a broader, more unified perspective on the structure of the universe. Like Minimal Primitivism, Adlam’s approach does not appeal to divine agency, relying instead on metaphysical principles that define the structure of spacetime as a whole (Adlam 2022).

Tyler Hildebrand and Thomas Metcalf (2021) propose a flexible interpretation of the laws of nature in their defence of Divine Voluntarism. In their view, the laws of nature are divine decrees – expressions of God’s will – that can be interpreted in various ways. As previously indicated, this perspective can be interpreted consistently with the constraint-view of laws of nature. In addition, Hildebrand and Metcalf refrain from labelling their interpretation a theistic model, as their conception of God does not rely on the notion of an infinitely perfect being characteristic of classical or Anselmian theism. Yet, their approach posits that God’s intentional act of creating and organizing the universe is reflected in the regularities and laws we observe. These regularities and laws allow for flexibility, especially in relation to moral and aesthetic values that may emerge in the universe. For Hildebrand and Metcalf, the laws of nature are not just brute facts but are imbued with purpose and intentionality, reflecting a god who desires an orderly and meaningful cosmos. As Hildebrand and Metcalf explicitly state, their Divine Voluntarism does not specify how God brings about regularities in nature. Their model remains compatible with various views, including occasionalism, dispositionalism, and natural kind essentialism (Hildebrand and Metcalf 2021, 467).

Decretalism, by contrast, is an explicit theistic model of laws of nature. Decretalism is a type of nomological realism that interprets the laws of nature as divine decrees established by God (Plantinga 2016). Alvin Plantinga, a recent proponent of this view, closely links decretalism with occasionalism. Plantinga distinguishes between strong and weak occasionalism in his exploration of the relationship between divine causation and natural laws. Strong occasionalism asserts that all events, whether mental or physical, are directly caused by God, implying that creatures do not have any causal power of their own. For instance, if a person decides to raise their hand, it is God who causes both the decision and the actual raising of the hand. This view raises significant problems, as it appears to make God the direct cause of all actions, including evil ones, which complicates the issues of moral responsibility and divine goodness. Conversely, weak occasionalism proposes that while God causes the physical outcomes of decisions, the creatures themselves are responsible for their mental decisions and intentions. In this view, a person’s decision to raise their hand is genuinely their own, but God causes the physical movement of the hand in response to that decision. This allows for human moral responsibility since individuals are the authors of their decisions and intentions while still positing that God brings about the physical effects of those decisions.

Plantinga finds weak occasionalism more tenable as it maintains human moral agency while addressing the challenges of understanding creaturely causation, striking a balance by attributing causation of mental events to creatures and physical events to divine action, thereby preserving the coherence of divine involvement in the world without compromizing human moral responsibility (Plantinga 2016, 138–141).

Jeffrey Koperski adopts a decretalist model of the laws of nature, aligning his view closely with that of Plantinga. However, unlike Plantinga, he rejects the idea that his position constitutes a form of occasionalism (Koperski 2024, 8). Koperski argues that early modern philosophers also adhered to a decretalist model of laws, but their assumption that these laws govern the dynamic evolution of all physical processes at every moment inevitably led to occasionalism. If God is the foundation of the laws of nature and these laws perform all causal work, then God appears to be the sole causal agent.

Koperski seeks to loosen the strong connection between decretalism and occasionalism by adopting the constraint view of the laws of nature as developed by thinkers like Chen, Goldstein, and Adlam. According to Koperski, if the laws of nature merely constrain rather than govern the entire evolution of physical processes, this allows for the possibility of causality within nature. However, Koperski maintains a theological foundation for these laws, distinguishing his view from the theological neutrality of Adlam or the Minimal Primitivism of Chen and Goldstein. Unlike Hildebrand and Metcalf, who refrain from committing to theism or a specific interpretation of the laws of nature, Koperski defends a theistic version of the constraint-view. In doing so, he offers a middle path, preserving divine sovereignty over natural processes while asserting that these constraints are sufficient to guide natural causality without requiring ongoing divine intervention.

Koperski has developed his argument for decretalism through several significant publications, evolving his position in response to critiques and new insights. In ‘Breaking Laws of Nature’, published in Philosophia Christi in 2017, Koperski introduced ‘decretalism’, claiming that the laws of nature are divine decrees. He argued that these laws, as expressions of God’s will, set natural processes in motion without requiring God’s continuous intervention. In the same journal, Robert Larmer critiqued this view in his 2017 article ‘Decretalism and the Laws of Nature’, arguing that Koperski’s position inevitably leads to occasionalism, where God is the only genuine cause, and natural entities lack causal power.

In his 2020 book, Divine Action, Determinism, and the Laws of Nature, Koperski refined his account by arguing that the laws of nature act as constraints rather than efficient causes. He used analogies, such as channels guiding a rolling ball, to illustrate that law determines possible behaviours without providing the ‘oomph’ or dynamic production required by other metaphysical views. This refinement aimed to distinguish his view from occasionalism more clearly.

In 2023, Larmer critiqued this updated model in his article ‘Koperski’s New (Improved?) Decretalism’, published in Philosophia Christi, arguing that the new account introduces more problems than it solves and still fails to avoid the implications of occasionalism. Larmer contended that despite the revisions, Koperski’s model remained problematic because it still implied that God was the direct cause of all events, given the lack of independent causal powers in natural entities. Koperski responded to this critique in his article ‘Decretalism Is (Still) Not Occasionalism: Reply to Larmer’, published in Philosophia Christi in 2023. In this response, Koperski clarified his position by emphasizing that laws of nature, as divine decrees, do not have their own ontology and do not govern events directly. Instead, they set constraints that define how things behave without requiring continuous divine intervention. He reiterated his rejection of dynamic production, arguing that forces, energy, and momentum in physics are sufficient to explain changes in physical systems.

Koperski’s most recent publication, ‘God, the Laws of Nature, and Occasionalism’, in Religious Studies, published in 2024, further clarifies and defends his position against such criticisms. He argues that his version of nomological realism, which sees laws as constraints set by God’s decrees, avoids occasionalism by rejecting the need for dynamic production. Instead, he posits that forces, energy, and momentum, as described by physics, are sufficient to explain changes in physical systems. In his opinion, this constraint-based approach maintains that laws set boundaries on natural behaviours without directly causing events, aligning better with contemporary physics and avoiding the theological and philosophical pitfalls associated with occasionalism. Through this ongoing dialogue, Koperski has continuously refined his position, aiming to provide a coherent account of divine action and natural laws that integrates both theological insights and scientific understanding.

Robert Larmer (2017, 2023), a prominent critic of Koperski, argues that decretalism collapses into occasionalism, particularly because it diminishes the causal role of natural entities. Larmer sees this as a significant flaw and seeks to avoid any conclusions that align with occasionalism. While we agree with Larmer that Koperski’s model indeed leads to occasionalism, we diverge from his broader critique.

Larmer’s rejection of occasionalism is rooted in two primary concerns: (1) the issue of free will and (2) the problem of evil, both of which he sees as central challenges. In contrast, we argue that these concerns are not unique to occasionalism but are challenges faced by all models of divine action; divine omnipotence with free will is a difficulty not only for occasionalism but also for concurrentism and mere conservationism. Similarly, the problem of evil is not exclusive to occasionalism but arises in any model that posits an omnipotent and benevolent deity, regardless of the role of natural causality.

Therefore, while important, these issues do not inherently disqualify occasionalism as a sound model of divine action. Unlike Larmer, we view occasionalism as a legitimate and viable alternative. Instead of rejecting occasionalism based on these broader concerns, we evaluate the internal coherence of Koperski’s claims. Our critique centres on whether Koperski’s version of decretalism genuinely avoids the implications of occasionalism and whether it truly preserves natural causality, as he asserts.

In the next section, we reconstruct his argument based on his latest work to ensure clarity and accuracy. Then, we present three key objections that explore the consistency of Koperski’s model and examine whether occasionalism might offer a more coherent explanation. We also address issues overlooked by Larmer, particularly regarding the complexities within decretalism and its implications for causal powers and divine action in the natural world.

As a caveat, we want to emphasize that our critique is focused solely on Koperski’s model of divine action. Our objections apply specifically to his model within the context of theism. We do not take issue with the constraint-view of the laws of nature itself, which we find unproblematic. In fact, occasionalism is compatible with this view and other interpretations of the laws of nature. Moreover, our objections do not extend to the view of Hildebrand and Metcalf, as they neither commit to theism nor reject it. Neither do they explicitly reject occasionalism. Their model remains compatible with both positions. With this clear, we can start by analysing Koperski’s decretalism in detail.

Koperski’s decretalism

In Koperski’s view of decretalism, the laws of nature are seen as constraints set by God, ensuring the order and regularity of the natural world without requiring continuous divine intervention. Decretalism contrasts sharply with Humeanism, which treats laws as either regularities observed in events or as propositions that organize scientific knowledge into a coherent system. Additionally, it stands in opposition to dispositionalism, which replaces the notion of laws with the internal capacities or causal powers of substances. Decretalism thus offers a unique perspective by maintaining that the regularities observed in nature are underpinned by divine commands, providing a theological foundation for the laws of nature that aligns with a realist interpretation.¹

Koperski argues that the concept of decretalism found its roots in the philosophical shifts of the early modern period when philosophers began to reject the Aristotelian view of nature in favour of a law-centric understanding (Koperski 2024, 2–4). During this time, thinkers like René Descartes, Isaac Newton, and Robert Boyle moved away from the idea that natural phenomena were driven by intrinsic dispositions or essences. Instead, they embraced the notion that the laws of nature were direct decrees from God. This transition was part of a broader rejection of Aristotelianism and its emphasis on substantial forms, which posited that objects had inherent purposes and causal powers. Some early modern philosophers, for example, Malebranche and Samuel Clarke, argued that God does not need intermediaries, such as these substantial forms, to govern the universe (Leibniz and Clarke 1956, 23; Malebranche 1980, 448–449; Clark 1998, 149; Nadler 2000, 112–138). Instead, God’s will alone was seen as sufficient to establish the order and regularity of the natural world. This shift laid the groundwork for the scientific revolution by encouraging a more empirical and experimental approach to understanding natural phenomena. By viewing the laws of nature as divine commands, early modern philosophers could attribute the predictable behaviour of the physical world to the consistent and rational will of a divine lawgiver, thus integrating theological perspectives with emerging scientific methodologies.

At the heart of Koperski’s decretalism is the argument that the laws of nature are divine decrees, which function as constraints rather than active causes; he posits that these decrees set boundaries within which natural phenomena occur, exemplified clearly in the functioning of conservation laws in physics. Unlike dynamic production, where laws actively cause events, this type of decretalism asserts that laws limit the possible behaviours of entities without directly instigating change in Koperski’s interpretation. For instance, the law of electrostatic force dictates how charged particles interact, but it does not actively push them; instead, it defines the constraints within which such interactions occur (Koperski 2024, 9–10). This approach rejects the notion of dynamic production or oomph traditionally associated with the laws of nature, thereby avoiding the need for laws to be seen as active forces responsible for the evolution of physical processes. Instead, the regularities and patterns observed in nature are the result of the causality of nature and God’s initial decrees, which establish the framework for natural processes. This perspective allows for a coherent integration of divine sovereignty with the empirical observations of science, asserting that while God’s decrees set the stage for natural law, they do not necessitate continual divine intervention in every natural occurrence.

Koperski’s version of decretalism aims to avoid the conclusion of occasionalism, which posits that God is the sole efficient cause of all events, thereby negating any type of natural causality. While occasionalism requires continuous divine intervention for any event to occur, Koperski’s decretalism asserts that God’s initial decrees set the laws of nature as constraints, according to which natural processes take place without requiring ongoing direct divine action. Koperski argues that these constraints allow natural causality within the limits established by divine decrees. For example, when a person pushes a coffee mug across a table, it is the contact force exerted by the person’s hand, not direct divine intervention, that causes the mug to move. This distinction is crucial for maintaining scientific realism, where natural forces and interactions are acknowledged as real and effective. By framing the laws of nature as constraints rather than dynamic producers of change, Koperski purports to show that his version of decretalism does not collapse into occasionalism (Koperski 2024, 8). This approach preserves the autonomy of natural processes while still attributing the ultimate origin of these processes to divine will, aiming to provide a balanced integration of theological and scientific perspectives.

Koperski anticipates and addresses several common criticisms of his decretalist framework by Larmer (2023). One critique is his use of anthropomorphic language, such as suggesting that nature forgets its constraints, which some readers might take literally. Koperski clarifies that these metaphors are intended to illustrate that God’s decrees are effective without requiring continuous divine intervention. Another criticism targets his rejection of dispositionalism and causal powers. Larmer argues that Koperski dismisses dispositionalism merely for its lack of precision. In response, Koperski emphasizes that the early modern rejection of Aristotelian dispositionalism favouring nomological realism was instrumental in the scientific revolution, enabling the discovery and formulation of various types of laws, including conservation laws. Additionally, he notes that dispositionalism struggles to account for laws that do not involve conditional change, such as conservation laws and least action principles. Furthermore, Koperski’s dismissal of concurrentism – a view where God and natural entities jointly cause events – was challenged by Larmer (2023, 112) for seemingly leaving no room for divine action within natural processes. Koperski counters by advocating for a neoclassical model of divine action that fits neither into mere conservation, concurrentism, nor occasionalism (Koperski 2020, 129–148). By addressing these criticisms, Koperski strengthens his argument that his version of decretalism is a coherent and robust alternative that integrates divine sovereignty with empirical science without falling into the extremes of occasionalism.

To summarize, Koperski’s decretalism offers a novel framework for understanding the laws of nature as divine decrees that function as constraints rather than dynamic forces. This approach builds on the historical shift from Aristotelianism to a law-centric view in the early modern period. While recognizing natural causality within the boundaries set by divine constraints, Koperski emphasizes the sufficiency of God’s initial decrees in establishing the framework for natural processes. By carefully distinguishing his position from occasionalism, Koperski maintains that nature has genuine causality, albeit within the limits imposed by divine decrees, thus preserving the integrity of scientific realism. Addressing various criticisms, he clarifies misconceptions and defends his view against challenges related to dispositionalism, concurrentism, and the use of metaphors. The philosophical implications of decretalism highlight its alignment with a simplified and coherent metaphysical framework that supports both empirical science and theological doctrines. Koperski’s refined version of decretalism thus claims to provide a robust alternative to traditional views, avoiding occasionalism while offering a parsimonious and theologically integrated explanation of natural laws. We argue that it doesn’t.

Three objections to Koperski’s decretalism

We now turn to a critical examination of Koperski’s position, focusing on three central objections that challenge the coherence and viability of his model. First, we examine his commitment to scientific realism and highlight how his failure to define his position clearly undermines the consistency of his argument. Second, we consider the principle of simplicity, arguing that occasionalism, as an alternative, offers a more parsimonious explanation of divine action and natural causality. Third, we address the reduction of Koperski’s model to occasionalism, demonstrating that his reliance on continuous divine sustenance effectively eliminates the causal independence of nature. These objections collectively build a comprehensive critique, questioning whether Koperski’s decretalism can truly distinguish itself from occasionalism.

First objection: issues concerning scientific realism

One primary reason for Koperski’s rejection of occasionalism is his view that it conflicts with scientific realism. Since Koperski (2024, 9) is committed to scientific realism, he consequently rejects occasionalism. There are four issues to consider here.

First, let’s assume that occasionalism is indeed incompatible with scientific realism. If this is the case, we must consider how Koperski might respond to someone who commits to occasionalism and rejects scientific realism. A critical issue here is whether there is an objective criterion for preferring scientific realism over occasionalism. Koperski does not provide such a criterion. Without this, one might adopt the stance of scientific anti-realism and thereby comfortably embrace occasionalism. In this context, Koperski’s position appears to be a choice rather than a substantiated argument. He merely aligns with scientific realism without offering any significant criticism of occasionalism. His opponent, favouring occasionalism, could similarly decide to reject scientific realism without facing a compelling counterargument from Koperski. This means that Koperski’s position does not extend beyond expressing a mere dissatisfaction with occasionalism, lacking a robust defence against it. To strengthen his argument, Koperski must provide a compelling reason why scientific realism should be preferred over occasionalism,² something he has not done. This omission leaves his critique of occasionalism underdeveloped and his preference for scientific realism as seemingly arbitrary.

Second, Koperski asserts that occasionalism conflicts with scientific realism but fails to specify which version of scientific realism he endorses. This omission results in an ambiguity about his stance on the nature of scientific explanations and their relation to causal relations. Scientific realism can take several forms, including entity realism, structural realism, and epistemic realism. Indeed, he is committed to a version of scientific realism that recognizes genuine efficient causation in nature. He says:

Oomph-free nomological realists deny that the laws govern. They are not responsible for change in nature. What is? At the level of physics, textbook answers are wholly adequate in accounting for change in terms of force, momentum, etc. No additional metaphysics is needed. Rocks fall because of gravity, not because of Aristotelian formal and final causes. What explanatory work has physics failed to do that requires metaphysical attention? (Koperski 2024, 10)

According to Koperski, efficient causes that are responsible for changes in nature are given to us in physics textbooks with scientific explanations or descriptions referring to force, momentum or gravity. Thus, he interprets terms such as ‘force’, ‘momentum’, or ‘gravity’ with a causal connotation. Are the physics books the criteria here to determine what is scientifically real or not? What is the scope of Koperski’s scientific realism?

In physics books, one may also encounter terms such as the centre of mass, which refers to a unique point where the weighted relative position of a distributed mass in space sums to zero.³ This is a theoretical construct that does not always correspond to a physical location, especially in coupled systems. For instance, the centre of the solar system is just a theoretical point in empty space where no massive body exists. Likewise, the meridian lines in geography books do not refer to real lines in the world. Saying that Japan is on the 135th Meridian East does not imply the existence of a physical line passing through Japan. In sum, what reason does Koperski give us to interpret terms such as force, energy, or gravity realistically, with causal connotations? If the only reason is that these terms are included in scientific descriptions or explanations, then we would need to interpretall such scientific terms realistically, including the centre of mass and meridians, which is absurd. Koperski needs to offer a more substantial reason for why his scientific realism must involve causal relations. However, no such reason is provided.

Third, in the quoted passage, Koperski asks, ‘What explanatory work has physics failed to do that requires metaphysical attention?’ He reiterates this by stating, ‘Physics explains changes of state in terms of forces, momentum, and energy potentials. There is no need for an additional layer of metaphysics to say why change happens’ (Koperski 2024, 9). However, interpreting forces, momentum, and energy potentials realistically – as forms of efficient causality – is already a commitment to a metaphysical position. As Hume rightly observed, we do not observe real causes in nature, only constant conjunctions. Ascribing causal links between correlated events involves adopting a metaphysical stance beyond mere observation (Larmer 2023, 114).

As a fourth and final point, Koperski’s claim that occasionalism is incompatible with scientific realism is also open to challenge. Depending on the particular form of scientific realism, one could adopt a version that aligns with occasionalism in the following way. Theoretical entities such as electrons, photons, or fields may still be considered real, while the regularities observed in their behaviour are treated as mere correlations, not as indicative of genuine causal connections. In this view, relational terms like ‘force’, ‘power’, ‘energy’, and ‘efficient causality’, typically understood as describing real interactions between natural entities, can be interpreted nominalistically. The entities themselves are regarded as real, but no causal efficacy is attributed to them. However, interpreting the concepts of force, energy, or power nominalistically does not imply that the laws of mechanical force or the conservation of energy are merely mental constructs. Within an occasionalist framework, these laws can be seen as contents of divine knowledge and will, as Plantinga’s decretalism suggests (Plantinga 2016, 136–140). This allows for a form of nomological realism rooted in God’s attributes without attributing the same ontological status to these laws as that of created beings. This version of scientific realism maintains that all causal power resides solely with God, thus reconciling occasionalism with scientific realism.⁴

Therefore, the question becomes how to judge between different metaphysical positions on this issue. On the one hand, there is occasionalism. On the other, there is the oomph-free nomological realism that Koperski defends. Why should we choose the latter? Koperski’s primary justification appears to be his commitment to scientific realism, which is neither clearly delineated nor particularly compelling.

Second objection: simplicity

Continuing from the last point, how can one choose one metaphysical position over another? A relevant criterion might be simplicity or Ockham’s razor: the theory that minimizes the number of entities or factors required to explain phenomena is preferable. Koperski’s view incorporates God’s volitions and recognizes natural causality. It is not a purely naturalist position that excludes God from explanations, nor does it consider God as the sole efficient cause, as occasionalism does.

When we compare Koperski’s view with occasionalism, we find that occasionalism fares better in terms of simplicity. Occasionalism posits only one real causal agent, God, to explain phenomena, while Koperski postulates natural causality in addition to God’s power. This raises the question: what is the point of postulating additional finite causal activity apart from God’s causality? It seems redundant. Since God is considered omnipotent, He can accomplish everything that finite causality is supposed to do. By introducing finite causality alongside God’s omnipotence, Koperski’s model complicates the metaphysical landscape without providing a clear advantage. If God’s omnipotence can account for all phenomena, then invoking additional finite causality seems unnecessary and overly complex.

Koperski is indeed aware of this point. When he describes the modern attitude of abandoning Aristotelian essences and powers in favour of laws of nature, he states, ‘God needs no help from created entities to govern’ (Koperski 2024, 3). A similar concern applies to Koperski’s oomph-free nomological realism: once you acknowledge the existence of an omnipotent God, postulating any type of natural causality becomes redundant.

While occasionalism may surpass Koperski’s view in terms of simplicity, one may question its explanatory strength. It could be suggested that occasionalism raises concerns about how we acquire knowledge of the world. If God is the sole efficient cause, including the cause of our mental states, then what we perceive as representations of the external world might merely be impressions placed in our minds by God without necessarily corresponding to any objective reality. This casts doubt on occasionalism’s ability to account for reliable knowledge of the world.

This issue, however, arises in any model of divine action that acknowledges God’s omnipotence. Suppose we assume that an external world exists independently of the human mind and that the causal interaction between this world and our minds guarantees the reliability of our knowledge. For example, the interaction between a tree and its environment, such as sunlight, causes us to perceive the tree, ensuring that we recognize a tree, not some imagined creature (like the beasts and monsters). However, if God is omnipotent, isn’t it possible that He could block the causality of nature and cause us to perceive something entirely different? This could occur in any model of divine action. The same possibility applies here. Thus, occasionalism cannot be criticized simply because God is the direct cause of everything, as this point is simply irrelevant. The crux of the issue is the possibility of perceiving a tree while, in reality, there is a monster in front of us. This possibility is valid whether or not one ascribes efficient causality to nature – if God wills it, it happens, regardless of the divine action model.

Second, occasionalists do not support a simplistic view where God arbitrarily creates things haphazardly in the world. Instead, they maintain that God creates the universe directly and in an orderly fashion, moment-by-moment. This is why Islamic occasionalists, such as the Ashʿarīs, argued that God acts in accordance with a consistent habit or custom that He freely chose and continues to sustain while still allowing for the possibility that He could alter it (Perler and Rudolph 2000, 54; Griffel 2009, 175–213). Modern occasionalists, like Malebranche, similarly embrace the concept of occasional causes and the laws of nature, viewing them as expressions of the regularity that god continually upholds in the universe (Malebranche 1980, 449). From this perspective, God would uphold a stable connection between the physical and mental states of the world, thereby ensuring a dependable epistemic link between divine action and human cognition.

Third, it is also questionable whether the concept of natural causality provides a stronger basis than occasionalism for securing our knowledge of the world. The view of natural causality assumes causal efficacy in nature based on pragmatic considerations rather than solid epistemic grounds. As Al-Ghazālī and Hume have pointed out, neither does observation offer conclusive evidence for natural causality nor is there an a priori argument establishing necessary connections in nature (Al-Ghazālī 1997, 166–167; Hume 1975, 79, 1955, 72–90). Natural causality is merely assumed to explain order and regularity and to justify that our mental representations of the world provide reliable knowledge. However, an occasionalist can make the same argument without invoking natural causality. Regularity in the world can be attributed directly to God’s actions, which offers a more parsimonious explanation. The security of our epistemic states can be grounded in God’s direct involvement, rendering the appeal to natural causality redundant and unnecessary.

Third objection: reduction to occasionalism

Building on Larmer’s critique that Koperski’s model diminishes the causal role of natural entities, we argue that Koperski’s insistence on God’s continuous sustenance leads to a reduction to occasionalism. Despite his commitment to some kind of natural causality, the reliance on divine sustenance undermines the causal autonomy of nature and results in God being the ultimate efficient cause of all natural phenomena. This extends Larmer’s concern, showing that Koperski’s model collapses into the very occasionalism it seeks to avoid.

Koperski assigns explanatory roles to both God and natural causality in his oomph-free nomological realism. However, despite his efforts to avoid it, we argue that his account essentially boils down to occasionalism. While Koperski attempts to affirm natural causality within the boundaries set by divine decrees, we will show that his reliance on God’s continuous sustenance undermines this claim, reducing his view to a form of occasionalism.

Koperski does not commit to any well-known models of divine action, such as concurrentism or mere conservationism, nor does he explicitly explain his own divine action model. His only explicit remark concerning God’s role is that God’s volitions determine the laws of nature, which he conceives as constraints on natural processes rather than the dynamic laws of early modern philosophers, along with sustaining the universe (Koperski 2020, 155). He is also clear that constraining laws do not imply any causal connotation; to him, laws constrain, and this constraining is not a causal activity, yet nature remains causally active (Koperski 2024, 10).

Koperski’s key claim is that God does not step in at each point of contact to be the sole causal agent in nature. He believes God’s one-time decrees are sufficient to establish regularities in nature, which natural processes follow autonomously. Koperski says:

God does not step in at each point of contact to be the sole causal agent in nature. I see nothing incoherent about God’s one-time-for-all decrees for what regularities nature will henceforth instantiate. A necessary condition is that God continues to sustain creation in existence, but that alone does not entail that God causes all events (Koperski 2020, 155).

While Koperski distinguishes his view from occasionalism by rejecting continuous divine intervention, his admission that God continuously sustains creation raises a critical issue. If God’s sustenance is a necessary condition for the existence and functioning of nature, then there is no genuinely autonomous natural causality. By acknowledging that God sustains the universe moment-by-moment, Koperski’s model aligns more closely with occasionalism: God remains the ultimate cause behind every event because natural phenomena depend on God’s continuous action for their existence and functioning.

At this point, Koperski’s model is subject to the same criticism Malebranche has brought to the proponents of secondary causality in nature. In Malebranche’s view, God’s continuous sustenance of the world amounts to continuous creation. As Malebranche argues:

Creation does not pass, because the conservation of creatures is – on God’s part – simply a continuous creation, a single volition subsisting and operating continuously. Now, God can neither conceive nor consequently will that a body exist nowhere, nor that it does not stand in certain relations of distance to other bodies. Thus, God cannot will that this armchair exist, and by this volition create or conserve it, without situating it here, there, or elsewhere. It is a contradiction, therefore, for one body to be able to move another (Malebranche 1997, 115).

In this passage, Malebranche emphasizes the necessary dependence of modes on their underlying substrate or substance. If we assume that God conserves the substances or foundational ontological items of the universe, it logically follows that He also produces the various accidents or modes of these substances or items, as modes cannot exist independently of their substance. However, Koperski avoids attributing causal powers to finite beings to steer clear of dispositionalism, which posits that entities have intrinsic powers or capacities. Instead, he refers to concepts like gravity, forces, momentum, and energy as sufficient to explain changes in physical systems. He grounds his ontology in quantum fields rather than particles (Koperski 2020, 136). He also acknowledges the emergentist perspective that higher-level phenomena are as real as quantum fields and that divine influence might extend to these phenomena (Koperski 2020, 136). Nonetheless, we can apply Malebranche’s argument to a field ontology, as Koperski seems to endorse.

In line with Malebranche’s reasoning, if God’s sustenance is required for the ongoing existence of the fields that form the basis of Koperski’s ontology, then God must also sustain all excitation events within these fields (e.g., particle interactions). The crucial point here is that particles and interactions within physical fields are not independent of the fields themselves. If these fields are sustained by God, then divine power necessarily extends to all physical processes occurring within them. This results in God’s direct involvement in every instance of causation. Despite Koperski’s claim that laws of nature only function as constraints, God’s continuous sustenance suggests that natural causality still depends on God’s volition, making God the ultimate efficient cause of all events. Thus, Koperski’s model begins to resemble occasionalism.

By grounding his ontology in quantum fields and dismissing the causal powers of finite entities, Koperski leaves no room for independent causality. Even if fields are responsible for particle interactions, these fields themselves are continuously sustained by God’s volition. The continuous sustenance of the universe by God necessarily entails the rejection of independent natural causality. Our analysis reveals that, although the constraint-view of the laws of nature may offer Koperski a potential escape from occasionalism, his reliance on divine sustenance ultimately negates natural causality. This leaves God as the direct cause of all events, making Koperski’s model functionally indistinguishable from occasionalism.

In conclusion, despite Koperski’s best efforts to avoid occasionalism, his insistence on God’s continuous sustenance of creation and his rejection of causal powers in natural entities leads to a model where God is still the ultimate cause of all events, reducing his framework to a form of occasionalism in practice, if not in name.

Conclusion

In this article, we have raised three central objections to Jeffrey Koperski’s model of decretalism, focusing on its internal coherence, simplicity, and alignment with scientific realism. We have argued that Koperski’s attempt to differentiate his model from occasionalism ultimately collapses, as his reliance on continuous divine sustenance undermines the independence of natural causality. Though Koperski seeks to preserve a role for natural causality within the boundaries of divine decrees, his model effectively reduces all causality to divine action, making it indistinguishable from occasionalism. While Koperski’s model offers an innovative interpretation of divine action, we have demonstrated that it faces significant philosophical challenges and fails to fully resolve the tensions it aims to address. Rather than offering a truly distinct alternative, Koperski’s decretalism reintroduces the very occasionalist framework it seeks to avoid.