While the stated topic of the book is divine action, the subtitle does a lot of work: Contemporary Science & Thomas Aquinas. Dodds believes that modern views of causality are impoverished, and that Aristotelian-Thomist metaphysics provides the remedy. While this is doubtful in my opinion, the mapping of medieval concepts to contemporary science should be helpful to Thomists and those in the conceptual neighborhood. If you’re not? Then the book is somewhat less valuable.

The Catholic University of America Press, 2012

Readers without some background in the history of philosophy will likely struggle with the unfamiliar metaphysics more than with the science. The key is to understand the many types of causality employed. Consider a traditional way to understand Aristotle’s four causes. Start with a marble statue of a gazelle. The sculptor is the efficient cause, bringing the potential statue from a block of marble into visible reality. The material cause is the marble itself, what the statue is made of. The artist’s purpose for creating the statue is its final cause, perhaps as a means of supporting his or her family. Finally, the shape of the statue that began with an idea in the artist’s mind is its formal cause. If it were instead a real gazelle, this cause would be the substantial form of “gazelleness,” as it were: the abstract nature of whatever it is to be a gazelle. Every natural entity is a combination of substantial form captured within (prime) matter.

Dodds laments the fact that Aristotle’s rich typology of causes has been reduced to just one (ch. 1). It is widely believed that the scientific revolution discarded all but efficient causes, which are still found in Newtonian forces (especially what physicists now call “contact forces”:  pushings and pullings of various types). On the bright side, Dodds argues that this narrow, reductionist view of causality has recently broadened out once more (ch. 2). “The new kinds of causality that contemporary science is discovering are strikingly reminiscent of the sorts of causality found in the philosophy of Aristotle and Aquinas” (p. 96).

Does Science Need Four Causes?

As a philosopher of science, I would say instead that Aristotle’s other three “causes” are not causes at all, and that science has all the resources it needs without the antiquated metaphysics. Let’s go through them again. Material cause? It’s not as if science ever stopped exploring matters of composition. Chemistry has always been about the underlying nature of observable materials, but chemists do not need the language of material causes to guide that research. Final cause? While early modern natural philosophers—the word ‘scientist’ wasn’t coined until the nineteenth century—denied that final causes were ubiquitous in nature, other teleological ideas remained. The goal-directed actions of people and animals play a role in the social sciences and in biology. Function is still a common idea in anatomy. In other words, if science needs teleology, it has the conceptual resources. Formal cause? Insofar as form is understood as Aristotelian substantial forms, then yes, it has been replaced by the notion of laws of nature. If, on the other hand, one is simply talking about structure or shapes (p. 13), then once again science already has the resources it needs.

In short, one might grant that there are examples in modern science that are somehow reminiscent of Aristotelian causality, but why should we care? Science has all the explanatory resources it needs without the four “causes.” There are good reasons if one is a Thomist:  Thomistic metaphysics is largely Aristotelian. As Dodds notes, if science is discovering new reasons to believe in substantial forms, then theologians should pay attention (p. 184). But I would question whether science is doing any such thing. It isn’t clear whether the connections between modern science and Thomism are any stronger than those claimed between science and Eastern philosophy (see the Tao of Physics).

Divine Action and Causality

There are still more types of causality needed for a Thomistic account of divine action. Every event in creation is said to involve both primary and secondary causes (pp. 190–193). God is the sole primary cause. All other causes bringing about some effect are secondary, which depend on the primary cause for their ability to act. In other words, no natural entity has the power to bring about any effect on its own.God is therefore thoroughly engaged in every aspect of creation, not just those events that we think of as miracles. The capacity to be active in the world is due to each being’s substantial form, which was created and is continually sustained by God. As such, God is the primary source for all creaturely activity. Properly speaking, every event involves a primary cause that enables a secondary cause. The effect is due to both (p. 191). Instead of distinguishing natural from supernatural events, Thomists argue that both continually work in conjunction.

Dodds’s final distinction is between principal and instrumental causality (p. 193). Principal causes are mediated by way of instrumental ones. When I use a screwdriver to turn a screw, I am the principal cause; the screwdriver is merely instrumental. From a broader metaphysical perspective, God is the principal cause “in every creaturely action” in the sense that God is the cause of being itself. All secondary causes, which are the only kinds that science can detect, are also instrumental.

The upshot for divine action is that God does not intervene to act in nature. For each entity in existence, God is its principal cause and for any given natural event, what we observe is merely a secondary cause, which is dependent on the primary. God is therefore thoroughly engaged in every aspect of creation, not just those events that we think of as miracles.

Thomas, Aristotle, and Dodds’s Audience

As an account of divine action, Dodds’s work is of special interest to two audiences. First are those Catholic scholars who favor Thomistic metaphysics. How the various types of causality map to modern science is not obvious, given that scientists do not explicitly employ them, and so some guidance is useful.Dodds needs to show why science needs Thomism and explain away the many advances that science made by rejecting it. Second are philosophers whose ontology has its roots in Aristotle’s substantial forms. Today, they would instead speak in terms of “causal powers” or “dispositions” to explain natural regularities, but they are all neighbors in the metaphysical landscape.

For those lacking a theological motivation for Thomism and who are not inclined toward causal powers, the value of the project is less clear. One concern in particular becomes far less worrisome. Dodds is critical of other models of divine action insofar as “they all tend to treat God as a univocal cause alongside of natural causes” (p. 153). For example, if God were to directly and immediately intervene to make an axe head float (2 Kings 6), that would be treating God as the same sort of cause as gravity. Many Thomists agree with Dodds that this is theologically improper as it denies God’s transcendence. I find this puzzling. As philosopher William Alston argued,William P. Alston, “Divine Action: Shadow or Substance?” in The God Who Acts: Philosophical and Theological Explorations, ed. Thomas F. Tracy (University Park: Pennsylvania State University Press, 1994), 53–54. to say that God brings about some effect in the world is simply to treat God as an agent. Why is that a problem? If there are no descriptions that rightly apply to both human beings and God, then it is hard to make sense of having been created in God’s image. Given the way that God and his acts are portrayed in the Bible, describing God as an agent or person is both apt and apparently acceptable to the One who inspired it.

Finally, there are tensions between medieval Thomism and modern science that Dodds does not explore. What we now think of as the scientific revolution involved the explicit repudiation of Aristotelian metaphysics.I take up these arguments in chapter 4 of Jeffrey Koperski, Divine Action, Determinism, and the Laws of Nature (London: Routledge, 2020). Formal causes and substantial forms were displaced by a rival idea: laws of nature. This was no minor change, but my experience is that only Aristotelian-Thomists like Dodds fully appreciate how radical a shift this was. They know better than most that their preferred metaphysical scheme was rejected by the likes of Descartes, Newton, and Boyle. Moreover, the new law-centered approach was wildly successful, which is why the language of laws is familiar and the many types of causality mentioned above are not. If the Thomistic scheme is true, isn’t it odd that it had to be set aside for the scientific revolution to proceed? It is possible, of course, that it was right all along, but scientists and philosophers of science tend to believe that success follows truth. In other words, if a theory turns out to be useful, that’s generally an indicator that it is at least approximately true. The idea of laws has been so successful that even naturalists have a difficult time doing without it, even though they do not like its theistic roots. If someone were to argue that we should return to Newtonian physics, he would both have to explain why such a move is necessary and account for the many successes of relativity and quantum mechanics. To complete the analogy, Dodds needs to show why science needs Thomism and explain away the many advances that science made by rejecting it.