Does the History of Science Provide Evidence for Atheism?

An assessment of Jeffrey Jay Lowder’s evidential argument for naturalism

Photo by Kevin Woblick on Unsplash

For many atheists, naturalism and science are synonymous. So is the success of science evidence for naturalism?

This article outlines an argument made by Secular Outpost’s Jeffrey Jay Lowder. We will then assess whether the history of science supports this argument. In particular, we will focus on the work of Peter Harrison — a specialist on medieval and early modern science.

Lowder’s assumptions

Below is a summary of Jeffrey Jaw Lowder’s argument for naturalism.

Background assumption (B): the universe is intelligible

Evidence 1 (E1): many phenomena can be explained naturalistically (Lowder I think uses this term synonymously with ‘the use of scientific methods’) — without appeal to supernatural agency

Evidence 2 (E2): the history of science provides numerous examples of supernatural explanations being replaced by naturalistic explanations [i.e. conclusions based on the use scientific methods]

Rival explanations:

• theism (T): omnipotent, omniscient, morally perfect person who created the universe
• metaphysical naturalism (N): the universe is a closed system, so nothing outside of this universe can affect it.

Lowder’s argument

1. E1 and E2 are known to be true
2. Probability of the evidence (E1 and E2) is much more likely given the background information (B) and metaphysical naturalism (Pr(E | B & N) >! Pr(E | B & T)
3. Prior probability of T not much more than N
4. Other evidence held equal, T is probably false

Methodological naturalism and science

Lowder, similar to other atheist philosophers like Paul Draper, argues science depends on a commitment to methodological naturalism:

“Scientists should not appeal to supernatural entities when they explain natural phenomena” (Draper, God, Naturalism and Science)

It’s important to distinguish methodological naturalism from metaphysical naturalism (“the complete denial of the supernatural”, Michael Ruse, Oxford Handbook of Atheism). Draper, and most atheist philosophers, are careful to clarify that metaphysical naturalism has not been conclusively demonstrated.

Their argument is more subtle. Science’s commitment to methodological naturalism, means there are metaphysical implications to the success of science:

And this means investigating the world as though ontological or metaphysical naturalism — the belief that there are no supernatural causes — were true. It follows that their naturalism is not “merely” methodological: it adopts, at least for the purposes of explanation, a working ontology, a set of assumptions about what kinds of entities are likely to exist.

(Dawes, In defense of naturalism. International Journal for Philosophy of Religion (2011))

Draper and others assume the ‘natural’ world is governed by laws untouched by God. Divine activity, which cannot be investigated using the scientific method, is a supernatural intrusion on the natural world:

Thus, it is this sort of direct divine activity that involves the violation of laws of nature and so brings theistic religions into conflict with a scientific understanding of the world. (Draper, God, Naturalism and Science)

Therefore, the success of science provides evidence against the plausibility of belief in God. If Lowder and Draper’s argument is successful, we would expect the history of science to demonstrate the triumph of naturalistic over supernatural explanations.

Questioning E2: supernaturalistic and naturalistic explanations in competition?

Lowder’s argument requires us to assume:

• ‘naturalistic’ and ‘supernaturalistic’ explanations are competing, rather than complementary, perspectives on reality(E1). The success of science is inevitably the failure of supernaturalism and vice versa.
• the history of science provides numerous examples of the defeat of supernaturalistic explanations by naturalistic (scientific) ones (E2).

Metaphysical naturalism posits these explanations are in competition. However, Peter Harrison, a historian of science, questions these assumptions:

…an appeal to the history of science in support of the putative failures of supernaturalistic explanation implies that an unproblematic distinction can be drawn between ‘natural’ and ‘supernatural’, and that this distinction was routinely operative in the history of science. This turns out to be mistaken.(Harrison, Naturalism and the success of science. Religious Studies 2020; 56: 274–291, p275)

Triumph of naturalism over supernaturalism?

Lowder, following Draper, argues that belief in God is inconsistent with a foundational assumption of science — the regularities of the universe (‘the laws of nature’):

Thus, because the natural sciences have established that the nomic regularities we call the laws of nature operate, not just here and now, but everywhere and always, it follows that the claim that God acts in the world, though not absolutely ruled out by science since it is possible that violations of laws of nature occur undetected by science, is nevertheless strongly disconfirmed. (Draper, God, Naturalism and Science)

However, the distinctions between natural and supernatural made by modern day naturalist were of limited interest to medieval scientists. Harrison argues it is problematic to read back these interpretations onto a very different historical period:

One of the implications of this approach is that there is no genuine difference between natural and supernatural events. Clarke, the most philosophically acute defender of the Newtonian system in the early eighteenth century, thus announced that,

‘the course of nature, truly and properly speaking, is nothing else but the will of God producing certain effects in a continued, regular, constant, and uniform manner’ (Harrison, Laws of God or Laws of Nature: Natural Order in the Early Modern Period, p68)

Divine intervention and the regularity of the universe

Lowder’s argument for the incompatibility between science and theism can be summarised below:

1. naturalism entails no divine intervention in the universe

2. theism predicts there will be divine intervention in the universe

3. all things being equal, naturalism is more likely to be consistent with the regularity of the universe.

Of course, if naturalism is true, by definition there is no divine intervention. Similarly, if theism is true, we would expect some divine intervention. So all things being equal, this favours naturalism. But only a little.

However, all things are not equal, as I’ve argued in an earlier article considering broader evidence on the intelligibility of the universe favours theism. The next article in the series will factor in this wider evidence in a Bayesian network.