Have science and religion been fundamentally at war throughout history? Are they incompatible? Has religion always held back scientific progress? These views may seem intuitive but few historians would defend them. Professor Peter Harrison looks at the complexity of science-religion interactions, including the cases of Galileo and Darwin, and considers how we frame the debate.

Can you introduce the sorts of issues and questions that arise in the study of science and religion?

I think it really depends on the disciplinary orientation of the people engaged in the conversation. It’s very much a multi-disciplinary field. Historians—and I count myself among them—are interested in the long history of relations between science and religion. Philosophers take a different stance. They are more interested in, for example, epistemological questions: the methods of science, to some extent the content of the sciences, and the possible tensions between scientific claims and religious claims. Sociologists are interested in the empirical issues of what people actually believe about these things. Sociologists are also interested in the specifics of how these respective communities—scientific communities and religious communities—actually go about the business of knowledge generation. And, of course, there are people in the sciences themselves who have a lot to say about these things as well. Those are a few examples.

As a historian, which aspects are you most interested in?

I’m most interested in how science and religion came to be essentialised such that we can talk about there being a relationship between them. The standard view is to think that today we’ve got science and religion, and that these things, or something analogous to them, are perennial features of human cultures. On this view, we look at history to see what essential relationship there is between them. I think that’s totally mistaken.

What we see happening in the West is the emergence of quite specific conceptions of religion during roughly the 17th century. The very idea of “religion”, then, is a distinctively modern, Western notion. “Science” too, to some extent. Our present understanding of what science is is also something we see developing over time. It’s really only in the 19th century that we get our current conception of the natural sciences as constituting a coherent body of disciplines that share some essential features.

So, “science” and “religion” as we understand them today haven’t been constant categories throughout history, and the idea of them as independent things that can relate to one another is a recent development?

If you look at the frequency of the word “religion”, no one talks about it much until the 17th century—this is true for English, originally Latin, and also the European vernacular languages, too. So, “religion” as a category is not really important to anyone until the modern period. With science, the practices that we regard as science went under a range of different labels. “Natural philosophy” is one, as is “natural history”, and “mathematical sciences” is other. These things are different in really important ways to what we regard as science.

Natural philosophy, as the name suggests, was part of the philosophical enterprise and as part of that enterprise was concerned to some degree with moral formation. Its theoretical scope extended to things like God, so natural philosophy would often include discussions of God and the soul. These topics were a clear part of its agenda. I don’t think anyone today would say that God falls within the agenda of the natural sciences. So, we have to be very careful not to project back our present conception of the subject matter and goals of science onto these activities in the past. They were actually quite different from modern science.

One way of grasping this is to think about the way that geographical territories change over time. If a historian were to claim that there was a war between Israel and Egypt at some time during the Middle Ages, we’d just know a priori that that was completely wrong. And it’s wrong because Israel is a modern state founded after World War II. Neither did Egypt exist as a nation state in the Middle Ages. To speak about a conflict in those terms is completely anachronistic.

Now, it doesn’t follow that the geographical territories that now comprise Egypt and Israel weren’t there. When I say there was no religion before the 17th century, I don’t mean there weren’t people worshiping God and praying and having certain beliefs and practices. But those beliefs and practices were not a part of this coherent idea that we call “religion”. There weren’t “religions” plural either. In much the same way, there were things that looked like scientific practices, but they weren’t gathered together under the same umbrella that we could recognise as “science”.

What considerations have shaped your book choices?

In a way, I’ve been less interested in recommending books that are introductions to the field—although the first book is useful for that. I’ve really been looking at books that have influenced my way of understanding. Although I don’t agree with everything in them, these books offer more creative and interesting ways of looking at this question than much of the standard literature, and certainly the popular literature, that focuses on conflicts between science and religion.

In different ways, these books contest the idea that there’s inevitable or intrinsic conflict between science and religion. Among historians, the idea that science and religion have always been at odds is a view held by virtually no one. But culturally, the idea is deeply entrenched. So, there’s a real disconnect between academia and the popular consciousness. Why is this? Why is the disconnect so strong?

This is a really interesting point. Science and religion haven’t been at loggerheads throughout all of history. For historians, there is no question about this. The crucial issue to think about is precisely the one that you just framed. Given that, why does this narrative have such a strong and powerful purchase in contemporary society? It appears to be a fairly default position. We see it in popular media, we see it in popular science writers, and we see it even in science and social science textbooks.

“Science and religion haven’t been at loggerheads throughout all of history. For historians, there is no question about this”

I think the answer to the question is that it’s part of a larger and deeply ingrained narrative about Western modernity. This narrative wants to see us as progressive, rational, scientific, and as a consequence of that we buy into a story that sees history moving away from mythological, magical, religious primitive understandings and towards scientific understandings. Part of that is constructing science and religion as competing ways of looking at the world, where science has got it right and is the progressive force. A key element of the historiography is that all societies are moving progressively away from religion to science and that conflict narrative is really a part of that. It’s what we believe about ourselves about modern human beings that links to this discredited notion.

A core element of the conflict thesis is that science and religion are competing for the same territory—that it’s somehow a zero-sum game.

That’s exactly right. In fact, the New Atheist writer Sam Harris puts it in exactly those terms—of it being a “zero-sum game”. The normative aspect of this, for him, is that it’s necessary that science must win the battle because science represents reason and religion represents prejudice and superstition.

But there are some religious approaches that do hold that science and religion compete for the same intellectual territory. Young earth creationism is the go-to example. Here, religious beliefs conflict directly with scientific theories. For creationists, a literal interpretation of Genesis is taken to defeat modern evolutionary theory as an explanation for the variety of life and the age of the earth.

We should be clear that when historians deny that there is perennial conflict between science and religion, they do not deny that there are episodes of conflict. With young earth creationism, there is clearly a competition to attempt to explain the same thing: the complexity and diversity of life and where it came from. Young earth creationism sees these essentially scientific questions and attempts to give an answer based on the Bible. Of course, you’re going to get conflict there. There’s no doubt about that. It’s interesting to recognise that young earth creationism is not a modern vestige of a longstanding thing. It’s a very new phenomenon—a literal reading of Genesis and the idea that Genesis teaches us something about science is a 20th-century thing.

Read 1 The Warfare Between Science and Religion: The Idea That Wouldn't Die Edited by Jeff Hardin, Ronald L Numbers, and Ronald A Binzley Read

Let’s take a look at the books. Your first book is The Warfare Between Science and Religion: The Idea That Wouldn’t Die. Can you tell us about this one?

Historians of science have been attempting to destroy this myth—that science and religion have been perennially at war—for the past 40 years or so. Nonetheless, as the subtitle of the book conveys, this is the idea that wouldn’t die. This book brings together a group of historian myth-busters who have been thinking about this question. It rehearses the scholarship that shows why this story is bad history, but it also goes further to look at some of the reasons for its persistence.

You mentioned earlier that we can talk about “episodes of conflict” in history. The ones that are perhaps most well-known are Galileo’s trial before the Inquisition (1632–3) and responses to Darwin in the 19th century, both covered in this book. But historians have also put pressure on the idea that these episodes are unambiguously conflicts between science and religion. Could you tell us about that?

These episodes are paradigmatic in the sense that we encounter them time and time again in the conflict narrative. They are taken to be exemplary instances, and this really goes back to the Enlightenment. The Enlightenment philosophes in France used Galileo as an example as a perennial battle between the church and knowledge. The Galileo case is quite complicated, but what’s going on there is that Galileo is arguing for a Copernican view. There’s some telescopic evidence for it, but it’s not conclusive.

There are very powerful scientific arguments against it—such as the lack of observable stellar parallax. This is the key scientific objection which wasn’t solved for some time. Crucially, there’s also a hypothesis that Galileo leaves out of his consideration: the Tychonic view of the solar system. This actually satisfied much of the observational data that Galileo had, without getting into the physical problems of putting the earth into motion which was really impossible given the contemporary physics. So, there was a science versus science element involved.

The other aspect is that Galileo also got into trouble because he attempted to do some biblical interpretation to support his view. As soon as he did that, he stepped into the camp of the theologians and that was the point at which he was regarded as having gone too far. It wasn’t just Catholicism moving into the territory of science—which they certainly did by forbidding Galileo to defend the Copernican view. Galileo had also moved into the territory of biblical interpretation. To Catholics, he took a Protestant position because Protestants claimed that they could interpret Scripture for themselves. In the context of most Reformation controversies, Galileo looked dangerous in a way that Copernicus—who actually authored the hypothesis—didn’t. The Copernican hypothesis had been around for 50 years or so before it started to appear to be problematic.

“Galileo also got into trouble because he attempted to do some biblical interpretation to support his view”

It is slightly different with Darwin. With evolution, there are religious issues at stake. This is part of what motivates young earth creationism: fundamental questions about the nature of human beings, the origins of morality, and the literal truth of the Bible. Darwin’s theory puts question marks against these in a way that the Galileo case doesn’t. It wasn’t evolution that generated difficulties but the method of natural selection, because it made evolution look like a random directionless process. Again, that appears to be inconsistent with Christian notions of a providential direction to history and the special place given to human beings.

But, as we say, history is complicated. Darwin has very powerful highly religious supporters and he has some scientific critics as well. And until we arrived at “the modern synthesis”, with its better understandings of genetics, there wasn’t a plausible mechanism for natural selection.

One of the virtues of this book is that it also looks at science and religion interactions in Islam and Judaism as well as Christianity. Traditionally, science and religion discussions have centred on Christianity in the West. Is this just Western bias or are there important historical reasons for the particular focus?

I think there are important historical reasons for the focus. In my view, because science emerges from a Western Christian context, science and religion questions have always been central to Western reflections about itself and western Christianity’s reflection about itself. If you look at the Eastern religions, the issues are far less acute. Whereas Islam and Judaism have parallel considerations.

Read 2 Science and Religion: Some Historical Perspectives by John Hedley Brooke Read

Your next book is Science and Religion: Some Historical Perspectives by John Hedley Brooke. This argues against trying to form one unifying narrative that they’re either intrinsically incompatible or always complementary.

This book is a classic. In a way, this was the work that articulated what’s often referred to as ‘the complexity thesis’. It opposes simplistic conflict narratives and indeed simplistic harmony narratives that say that everything was always sweetness and light between religion and science. By looking very carefully at specific historical episodes, Brooke shows that the story is really complicated. We have some instances of conflict, but we also have episodes where it’s clear that religious factors were important for getting certain scientific views up and running, by motivating scientists, by providing essential presuppositions, and so on. And for at least some of time, science and religion just don’t have that much to do with each other. I think much of the story in the last couple of centuries has been that they go their own paths independently with only a few points of tension.

“We have some instances of conflict, but we also have episodes where it’s clear that religious factors were important for getting certain scientific views up and running”

John Brooke was not the only person to make this sort of argument. At the University of Wisconsin, two historians—David Lindberg and Ronald Numbers—had a 1986 collection of essays called God and Nature that also ran a similar thesis. So, a number of historians had been coming up with this notion of the complexity of science-religion relations, but John’s book is the authoritative statement of this notion of historical complexity.

I think this is a point that Brooke recognises, but this book has become more well-known for deflating the conflict myth than for putting pressure on the harmony myth. And yet it does both. Do you think that there’s a revisionist counter-current that exaggerates harmony between science and religion?

I think so. My own view is that there is more to the harmony story than to the conflict story. If we ask why science emerged in the West when it did, religion gives us much of the answer to that question. If you want to know what the key cultural ingredients are needed to get something like a scientific culture up and running and, crucially, give it social legitimacy, religion provides an important element of that. But there are crude versions of the harmony story that I think are problematic as the conflict narratives.

I also think you’re correct to point out that John’s work—and the complexity thesis in general—have sometimes been read as an advocating of harmony by those who want to keep arguing for the conflict story. But they are not. An example of this would be Yves Gingras’ recent book Science and Religion: An Impossible Dialogue, where he accuses historians of being religious apologists. That’s complete nonsense, but it’s indicative of the fact that simply challenging the conflict myth often leads to the perception of necessarily advocating some sort of harmony.

As well as conflict, harmony, and complexity, there are also people who argue for an “independence” thesis. This is the idea that science and religion are completely independent, with separate, non-overlapping domains. It seems more of a normative claim—that religion and science should keep to themselves and not interact—than a descriptive one. But let’s suppose there was a skeleton found in Jerusalem forensically proved to be Jesus of Nazareth (in other words, that a bodily resurrection didn’t happen). That seems to be a case where scientific research would have immensely significant religious implications.

It’s partly a descriptive claim because very often science and religion go their own way. But you can’t avoid the fact that if the propositional claims of the various religions are true, then empirically they must make some difference to how the world is. There will necessarily be some touchpoints in that case because science deals with the empirical facts. Unless a religion is restricted purely to the realm of the moral, it will make at least some substantive claims about empirical reality.

The independence view seems quite attractive, but it’s not quite right. And in someone like Stephen Jay Gould’s view, science takes what it wants and whatever is left over is dealt with by religion. So it’s not without its problems, not least because there are points of contact that can’t be avoided.

And we can’t assume that those points of contact will be inherently compatible.

That’s right. Part of the reason for that is that the contingencies of history and the fact that scientific theories change over time. Taking the long view, you can’t predict in advance that science and religion will always be independent and there’s never any possibility of contact. Historically, it depends on what scientists might be claiming at a particular time.

Read 3 Science, Technology & Society in Seventeenth Century England by Robert K Merton Read

Your next book is Science, Technology and Society in Seventeenth-Century England by Robert K. Merton. This is a classic work of sociology, but what does it have to tell us about science and religion?

As you say, it’s a classic sociological work. What I like about it is that Merton looks at a relatively constrained case of a specific time period in a specific place. He’s trying to explain why we get this efflorescence of scientific activity in England in the middle decades of the 17th century. This is when the Royal Society was founded, and considerable progress was made towards establishing the foundations of early modern science. Merton offers us a middle-range theory, as he would call it. It’s not a grand theory, but he’s not giving up on offering a proper explanation for what’s going on.

What’s particularly interesting is that he treats science itself as a kind of ‘black box’ and focuses on external factors and, crucially, values. He argues that Puritan values were important to setting up science and justifying scientific practice. That’s the key thing about this book. He understands that more generally, social values are crucial to the legitimation of science. That means it’s not just to do with the inherent internal logic of science as something that is somehow self-evidently true. That’s not how you make science successful—it’s something external to the sciences that leads us to value them, that makes scientific advance possible, and that makes science an important and central feature of society.

Why this question is so vital to this very day is that science is undergoing challenges to its legitimacy. It’s simply not enough for a scientist to rehearse the chorus ‘well, we’re scientists and this is what the science tells us’; they have to understand the role played by values in giving legitimacy to what they’re doing. I should add that there’s a number of difficulties with Merton’s book around some of the specifics. He wanted to argue that it was a puritan ethos that was distinctive for the rise of modern science. I think there are difficulties with who gets to be identified as ‘puritan’ and so on, but the general approach is very fruitful.

You said that the focus is on a very specific time in a very specific culture, but does the case generalise?

That’s a good question. I think it does generalise. Stephen Gaukroger is a historian and philosopher of science at the University of Sydney who is writing a long series of books on the emergence of the scientific culture in the West. What Gaukroger argues—rightly, in my view—is that part of the explanation for why we have science in the West is to do to with these issues of religious legitimation.

The contrast cases are the boom-bust patterns where scientific activity gets started in China, medieval Arabic cultures, and ancient Greece, but does not consolidate into a central and ensuring part of the culture. So, the question is not just about the origins of science, but also about its consolidation. That then leads to the question of social legitimacy, which then takes us to the question of which cultural values underpin science. For me in the West, it is religious values that helped give science a boost and consolidate its position as a legitimate and important activity. That’s another reason I like this book—Merton put his finger on something that is more generalisable than the specific case he dealt with.

Is it a problem for this argument that many of the titans of the scientific revolution like Copernicus and Galileo were Catholics?

It’s not a problem for Merton, but it is a problem for the more general story that I’ve just told. He would be completely unembarrassed by that because he was focussing on a very particular time and place. But moving from the specific case to the more general argument takes a lot of work. I don’t think you can say that it is just Protestantism alone that’s responsible for modern science. We have key Catholic thinkers like Galileo and Descartes (whose contributions are often underrated).

“The question is not just about the origins of science, but also about its consolidation”

But interestingly both Galileo and Descartes ran into difficulties with the Catholic Church. Things were more difficult for them. Protestantism in one sense was more open to new ideas than Catholicism and it was easier for Protestants to attack authorities like Aristotle than it was for Catholics. And that made a difference.

The extent to which religion contributed to the development of modern science is controversial. Christianity had been dominant in the West for centuries and centuries before the scientific revolution. This raises the question of why it didn’t happen sooner. I suppose that if we’re looking for an adjacent revolution in religious thought then it would be the Reformation. But we’ve resisted the claim that Protestantism alone is responsible for modern science.

We need to remember that the Reformation is a Catholic movement. It originates within Catholicism. And then Catholicism has its own Reformation, or as it’s sometimes called the ‘Counter-Reformation’. The other thing we need to understand is that the Protestant Reformation has unintended consequences that change the whole face of Europe. When we talk about the role of Protestantism and the rise of science, we’re not simply speaking about specific Protestant doctrines or practices. We’re talking about what happens to the West as a consequence of the Reformation. To return to the general question about Christianity and why the scientific revolution wasn’t earlier, then, the Protestant Reformation is part of that story. But there are other factors, in including material ones.

Nothing much is happening after the fall of Rome until we get the rise of the universities in the 13th century. But this hiatus owes more to material factors than ideological ones. Then, when the universities do get up and running, the intellectual environment is dominated by Aristotelian natural philosophy. Here again, the Reformation plays some role, because it gives people the scope to reject that synthesis of Aristotle and Christian theology so powerfully articulated by thinkers like Thomas Aquinas. Protestant Reformers attacked Aristotle as a pagan influence on Christianity, which needed to be purged from the tradition. That then gave legitimacy to a rejection of Aristotelian natural philosophy, which made space for other ways of understanding the natural world, including the theories of the new sciences.

What would you highlight as the most significant non-religious contribution to the emergence of scientific culture?

It’s a good question. As an intellectual historian, I deal in the realm of ideas, but there are material practices that are really important, along with the development of specific technologies. The invention of the telescope is one good example. Without the telescope, would these things have happened? What about the printing press? We get networks of communication, we get new technologies, and we have the capacity to make new instruments, like the air pump that individuals like Robert Boyle put to good use. So, there’s a range of material factors that are really quite important. While these are not part of my purview, I’m quite happy to acknowledge them as key.

Read 4 Theology and the Scientific Imagination by Amos Funkenstein Read

Let’s move on to Theology and the Scientific Imagination by Amos Funkenstein.

This book came out in the 1980s, even before John Brooke’s complexity thesis. It’s a powerful statement of continuities in medieval thinking about divine omnipotence—the all-powerfulness of God—and how this idea played out in very interesting ways in the formation of modern science. At a time when no one was really talking much about how specific theological ideas may have had an impact on the emergence of modern science, Funkenstein’s book is a milestone. We can go back to Merton for the sociological stuff, but in terms of the specific theological ideas, we can go to Funkenstein. It is a real masterpiece. His knowledge of the sources is really impressive, in showing how these ideas and debates of the operations of God’s power in the world had a direct impact on scientific thinking.

Can you give an example of how ideas about God’s omnipotence or omnipresence could be linked to scientific thinking?

Let me start with omnipotence, because that’s a slightly simpler case. The concept of laws of nature is a modern concept that we see most explicitly articulated first by Descartes. Descartes talks about laws of nature as God directly impinging on natural order, immediately moving objects around in lawful fashion according to his choice of a particular set of laws. So, the idea of a law of nature is that God chooses to instantiate regularities in the world and we need to go out and discover what they are.

This is very different from Aristotle’s idea that the order of the world is a function of the inherent properties that things have. To overgeneralise somewhat, with the new views of Descartes and Newton, the powers of things are stripped away—they become inert—and God has to do the work of moving things around. He does according to his own laws. The notion of divine omnipotence—that God can make any kind of world he wants and is not constrained by any other considerations—then leads to the necessity of empirically investigating the world. That’s one example: the idea of laws of nature and mathematical laws of nature which are foundational to modern science come out of the idea of divine omnipotence. Descartes is explicit about this, and so too are English thinkers like Robert Boyle, Isaac Newton, and Samuel Clark. They are very explicit that laws of nature are divine edicts.

“The idea of laws of nature and mathematical laws of nature, which are foundational to modern science, come out of the idea of divine omnipotence”

The omnipresence link is really quite complicated. It’s interesting because the debates that we see between Leibniz and Newton about whether space is absolute or relative actually hinge on theological questions to do with divine omnipresence. The Newtonian position is that if God is omnipotent, he must be present where he is active. His omnipresence, then, is what makes possible his acting everywhere. For Leibniz, this looks suspiciously like a form of pantheism—God has a body and that body is space. Newton comes very close to this in one edition of the Optiks where he talks about space as God’s ‘divine sensorium’ or sense organ.

One of the claims that Funkenstein makes towards the end of the book is that while one “can draw many meaningful connections between medieval theology and early modern science”, the stronger claim that “without the former, the latter would never have emerged” is “neither demonstrable nor plausible.” Do you disagree?

I think I would. I’d be inclined to say that the medieval theological background is necessary but not sufficient. That would be my view, which is a bit stronger than Funkenstein’s claim.

You’ve mentioned that this book is partly a continuity thesis, but I also want to ask about discontinuity. A classical view of the Enlightenment is that we see a disentangling of religious concepts from scientific concepts. By the 19th century, scientific literature had been completely purged of theological language. What are the key reasons for this division between the two? And is this disentangling a liberation?

I think the timing of the separation between the two is often got completely wrong, and Funkenstein is a good example of why that’s the case. It’s often thought that the scientific revolution takes place when science and religion are separated out. But what Funkenstein shows—and I think he’s exactly right—is that they actually come closer together in the 17th century. He talks in this context about “secular theologians”, meaning that for the first time, natural philosophers start to make theological claims and that would have been very unusual in the Middle Ages.

The whole structure of the medieval university was set up so that the faculty of arts where natural philosophy was taught was separate from the theological faculties. That was done quite deliberately. Natural philosophers (scientists, we would call them) typically did not make theological claims. But in the 17th century, we find that people like Descartes, Kepler, and Newton are all making theological statements. Part of the reason for this is that theological considerations are central to the way they’re thinking about the world. So, what actually happens is that science and religion come together in the 17th century in a way that would have been very unusual in the Middle Ages.

“Science and religion come together in the 17th century in a way that would have been very unusual in the Middle Ages”

The question is: when do they come apart? That happens definitively in the 19th century. Why they came apart is another complicated story, but in England one of the reasons was because scientists wanted to assert their independence from ecclesiastical strictures. There was a professional component. People like Thomas Henry Huxley had an explicit mission to use science, e.g. evolutionary thinking, to liberate science and scientific institutions from theological constraint. For Huxley and his fellow travellers, the union of theology and science was a problem. And at some level I think it was.

Your second question—whether it’s a good thing that they’re separate—is a hard one to answer. If those like Merton, Funkenstein and me are correct in thinking that theology was really crucial to the efflorescence of science in the 17th century, counterfactually we might ask if there is something lacking in science today that might limit its prospects. The question for me is: what makes science fruitful? Clearly, the advocacy of something like intelligent design or scientific creationism in present circumstances is absolute heresy. And I want to be clear that I am not advocating that. But I do think it’s very interesting to consider whether religious conceptions might lead to unconceived possibilities in terms of contexts of discovery. This is precisely Funkenstein’s point—that thinking about divine omnipotence and what God could possibly instantiate led to new ways of thinking about the world. This was also argued even more strongly by the French historian and philosopher of science Pierre Duhem.

The agnostic or atheist response to that would be that once science is removed from a religious metaphysics, then the presuppositions that limit the investigation are widened because it doesn’t have to operate within the boundaries of religious belief.

But we can also look at that the other way around. I wonder whether the very strong naturalism which either explicitly or implicitly shapes virtually all modern thought is in some way restrictive. Your point is that specific religious dogmas are potentially restrictive, and I think that’s absolutely right. But there’s a difference between specific religious dogmas and thinking in more elaborate theological terms about something like divine omnipotence (which is the historical case I’m thinking of). To put it this way, I don’t buy the idea that scientific naturalism is some neutral position and that the religious position is the one invested in a set of restrictive assumptions. I think naturalism is potentially just as dogmatic and restrictive.

Read 5 The Empirical Stance by Bas van Fraassen Read

I think that leads perfectly to your final book choice. This is The Empirical Stance by Bas Van Fraassen, one of the leading philosophers of science. This involves reflections on empiricism, the nature of scientific inquiry, and its relation to secularism. Can you tell me why you’ve picked this one?

This book was van Fraassens’s Terry Lectures that he gave at Yale in 1999. These lectures are often devoted to topics of science and religion. What I like about this book is that very few philosophers of science have been that interested in the science-religion questions, and here we have one of the leading analytic philosophers of science attempting to grapple with those questions in a very sophisticated way.

One of his targets is this strong version of naturalism or physicalism or materialism which is associated with Australian analytic philosophy—with Jack Smart and David Armstrong. He sees these guys and others as trying to mould philosophy into the image of science, as attempting to hold beliefs that lead to an implicit metaphysics. As the title of the book suggests, what he thinks philosophers of science should have is not a set of beliefs and metaphysical commitments, but rather a “stance”. For him, a stance is less dogmatic and restrictive. Take empiricism, for example: instead of focusing on the content and metaphysics of science, you look at its procedures and how it generates knowledge. I think that is a much more fruitful way for philosophers to think about science, rather than postulating normative claims about what its commitments or procedures ought to be. They should observe what’s going and see how science is constructed.

This is why, interestingly, he’s somewhat sympathetic to philosophers like Paul Feyerabend who are usually seen as quite radical and relativist. Feyerabend’s famous claim is that there’s no scientific method and that ‘anything goes’. What he means by that is that if you actually look at scientific practices, you see that scientists will do whatever it takes to get the outcomes. What you won’t find is a set of tightly defined and prescriptive methods that they operate with. As a historian, I’m very sympathetic to that view, because that’s essentially what historians do. They want to look at how it is that people come to generate knowledge in real life, without dictating what the process should be.

Part of what van Fraassen is exploring in this book is what he calls “objectifying inquiry” which he sees as characteristic of science. He’s looking at the principles governing science: how it proceeds in an impersonal way, how we take our own interests “out of the picture”, but how it also has pre-defined ideas of what counts as relevant for scientific explanation. But he rejects that it’s the only reasonable stance one can take towards the world. He thinks there can be “an abiding astonishment not allayed by the fruits of scientific inquiry.”

I think van Fraassen’s worry is that naturalism is a commitment that we don’t have to make. It’s not required for the success of science. The question is what the minimal things are that we need for a successful science. We understand science to be an empirical activity—scientists work in the realm of appearances. By way of contrast, claiming to know what lies behind the appearances can lead to a problematic and dogmatic metaphysics. For van Fraassen, the dominant naturalist metaphysics is one that leaves no room for human beings in our picture of the world. What will follow from that is a position that leaves religious and moral considerations out of the picture. He wants to have an understanding of the operation of science but in a way that we still have a view of the world that can still accommodate us, and along with that, ultimately, a religious dimension.

From the outset, the way that science is calibrated means that supernatural concerns are just not on its radar. This is a commitment known as ‘methodological naturalism’ and is a core part of the scientific method. Science gives naturalistic explanations of the natural world. But a common view sees science itself as committed to the positive claim that only natural things exist (‘metaphysical naturalism’). In other words, there are no supernatural entities such as God. That’s a strong metaphysical claim that is not entailed by the scientific method.

The question goes to what the connection is between methodological naturalism—the stance we adopt when we do science and that excludes supernatural explanations—and the more powerful claim that naturalistic explanations are the only ones that there are, or should be. In my view, it’s illegitimate to claim that methodological naturalism entails metaphysical naturalism. There are some interesting arguments that attempt to link those together, but I don’t find them persuasive. But neither should we deny the great power of the naturalistic stance.

And this is relevant when we consider the distinguished scientists today who are religious and thus believe in the supernatural. As van Fraassen notes, “If science is an enterprise with clearly discernible criteria of success, it has no need of a secular or any other loyalty oath”. A good scientist is measured by what they do in the laboratory, not in church.

As you say, the existence of Christian scientists who are not obviously subject to cognitive dissonance is an embarrassment for some who would claim the incompatibility of science and religion (as, for example, the New Atheists did). The fact is that there are now eminent scientists who have religious commitments, as there have always been throughout history. This is an awkward fact for advocates of the incompatibility of science and religion

Finally, I want to ask: when we’ve discussed positive contributions from religion to science, especially the scientific revolution, these have come from within a strong religious culture. But now, in western Europe, it’s a lot more secular. With this shift in mind, what are the lessons we can learn from the historical dynamics of science-religion interactions for the present day?

That’s interesting. One thing that the Galileo Affair has taught the Catholic Church is that it’s not wise to meddle in the scientific realm—that there shouldn’t be religious interference in scientific activity. I think that lesson has been learned. For me, there is the nagging question of the legitimacy of modern science and whether it needs external sets of values to support it. Although it may now seem to be largely self-sustaining in terms of the technology it generates and the knowledge it gives us, there’s a question of whether science is sustainable without a set of cultural values that support its mission. If you think about climate change scepticism, anti-vaxxers, and to some extent young-earth creationism, there are forces arrayed against it.

“One thing that the Galileo Affair has taught the Catholic Church is that it’s not wise to meddle in the scientific realm”

Also, government instrumentalities seem to be increasingly less willing to fund blue skies research—curiosity-driven science—and they are far more interested in specific applications. I think that’s a long-term danger to a science that sees itself exploring questions of genuine interest as opposed to just being involved in busy work to produce widgets for people who want better iPhones and so on. A better example would be improvements in health. This is not a particularly happy note to end on, but I think that if we’re too utilitarian in our approach to science—and this goes to questions of intrinsic value as opposed to utility—this could kill off genuine scientific inquiry in the long term.