Science and Religion are Not Compatible

Jerry Coyne, an evolutionary biologist at the University of Chicago, has recently published a book called Why Evolution is True, and started up a blog of the same name. He’s come out swinging in the science/religion debates, taking a hard line against “accomodationism” — the rhetorical strategy on the part of some pro-science people and organizations to paper over conflicts between science and religion so that religious believers can be more comfortable accepting the truth of evolution and other scientific ideas. Chris Mooney and others have taken up the other side, while Russell Blackford and others have supported Coyne, and since electrons are free there have been an awful lot of blog posts.

At some point I’d like to weigh in on the actual topic of accomodationism, and in particular on what to do about the Templeton Foundation. But there is a prior question, which some of the discussion has touched on: are science and religion actually compatible? Clearly one’s stance on that issue will affect one’s feelings about accomodationism. So I’d like to put my own feelings down in one place.

Science and religion are not compatible. But, before explaining what that means, we should first say what it doesn’t mean.

It doesn’t mean, first, that there is any necessary or logical or a priori incompatibility between science and religion. We shouldn’t declare them to be incompatible purely on the basis of what they are, which some people are tempted to do. Certainly, science works on the basis of reason and evidence, while religion often appeals to faith (although reason and evidence are by no means absent). But that just means they are different, not that they are incompatible. (Here I am deviating somewhat from Coyne’s take, as I understand it.) An airplane is different from a car, and indeed if you want to get from Los Angeles to San Francisco you would take either an airplane or a car, not both at once. But if you take a car and your friend takes a plane, as long as you both end up in San Francisco your journeys were perfectly compatible. Likewise, it’s not hard to imagine an alternative universe in which science and religion were compatible — one in which religious claims about the functioning of the world were regularly verified by scientific practice. We can easily conceive of a world in which the best scientific techniques of evidence-gathering and hypothesis-testing left us with an understanding of the workings of Nature which included the existence of God and/or other supernatural phenomena. (St. Thomas Aquinas, were he alive today, would undoubtedly agree, as would many religious people who actually are alive.) It’s just not the world we live in. (That’s where they would disagree.)

The incompatibility between science and religion also doesn’t mean that a person can’t be religious and be a good scientist. That would be a silly claim to make, and if someone pretends that it must be what is meant by “science and religion are incompatible” you can be sure they are setting up straw men. There is no problem at all with individual scientists holding all sorts of incorrect beliefs, including about science. There are scientists who believe in the Steady State model of cosmology, or that HIV doesn’t cause AIDS, or that sunspots are the primary agent of climate change. The mere fact that such positions are held by some scientists doesn’t make them good scientific positions. We should be interested in what is correct and incorrect, and the arguments for either side, not the particular beliefs of certain individuals. (Likewise, if science and religion were compatible, the existence of thousands of irreligious scientists wouldn’t matter either.)

The reason why science and religion are actually incompatible is that, in the real world, they reach incompatible conclusions. It’s worth noting that this incompatibility is perfectly evident to any fair-minded person who cares to look. Different religions make very different claims, but they typically end up saying things like “God made the universe in six days” or “Jesus died and was resurrected” or “Moses parted the red sea” or “dead souls are reincarnated in accordance with their karmic burden.” And science says: none of that is true. So there you go, incompatibility.

But the superficial reasonableness of a claim isn’t enough to be confident that it is true. Science certainly teaches us that reality can be very surprising once we look at it more carefully, and it’s quite conceivable that a more nuanced understanding of the question could explain away what seems to be obviously laid out right in front of us. We should therefore be a little more careful about understanding how exactly a compatibilist would try to reconcile science and religion.

The problem is, unlike the non-intuitive claims of relativity or quantum mechanics or evolution, which are forced on us by a careful confrontation with data, the purported compatibility of “science” and “religion” is simply a claim about the meaning of those two words. The favored method of those who would claim that science and religion are compatible — really, the only method available — is to twist the definition of either “science” or “religion” well out of the form in which most people would recognize it. Often both.

Of course, it’s very difficult to agree on a single definition of “religion” (and not that much easier for “science”), so deciding when a particular definition has been twisted beyond usefulness is a tricky business. But these are human endeavors, and it makes sense to look at the actual practices and beliefs of people who define themselves as religious. And when we do, we find religion making all sorts of claims about the natural world, including those mentioned above — Jesus died and was resurrected, etc. Seriously, there are billions of people who actually believe things like this; I’m not making it up. Religions have always made claims about the natural world, from how it was created to the importance of supernatural interventions in it. And these claims are often very important to the religions who make them; ask Galileo or Giordano Bruno if you don’t believe me.

But the progress of science over the last few centuries has increasingly shown these claims to be straightforwardly incorrect. We know more about the natural world now than we did two millennia ago, and we know enough to say that people don’t come back from the dead. In response, one strategy to assert the compatibility between science and religion has been to take a carving knife to the conventional understanding of “religion,” attempting to remove from its purview all of its claims about the natural world.

That would be the strategy adopted, for example, by Stephen Jay Gould with his principle of Non-Overlapping Magisteria, the subject of yesterday’s allegory. It’s not until page 55 of his (short) book that Gould gets around to explaining what he means by the “magisterium of religion”:

These questions address moral issues about the value and meaning of life, both in human form and more widely construed. Their fruitful discussion must proceed under a different magisterium, far older than science (at least as a formalized inquiry) and dedicated to a quest for consensus, or at least a clarification of assumptions and criteria, about ethical “ought,” rather than a search for any factual “is” about the material construction of the natural world. This magisterium of ethical discussion and search for meaning includes several disciplines traditionally grouped under the humanities–much of philosophy, and part of literature and history, for example. But human societies have usually centered the discourse of this magisterium upon an institution called “religion”…

In other words, when Gould says “religion,” what he means is — ethics, or perhaps moral philosophy. And that is, indeed, non-overlapping with the understanding of the natural world bequeathed to us by science. But it’s utterly at variance with the meaning of the word “religion” as used throughout history, or as understood by the vast majority of religious believers today. Those people believe in a supernatural being called “God” who created the universe, is intensely interested in the behavior of human beings, and occasionally intervenes miraculously in the natural world. Again: I am not making this up.

Of course, nothing is to stop you, when you say the word “religion,” from having in mind something like “moral philosophy,” or perhaps “all of nature,” or “a sense of wonder at the universe.” You can use words to mean whatever you want; it’s just that you will consistently be misunderstood by the ordinary-language speakers with whom you are conversing. And what is the point? If you really mean “ethics” when you say “religion,” why not just say “ethics”? Why confuse the subject with all of the connotations that most people (quite understandably) attach to the term — God, miracles, the supernatural, etc.? If Stephen Jay Gould and the AAAS or anyone else wants to stake out a bold claim that ethics and moral philosophy are completely compatible with science, nobody would be arguing with them. The only reason to even think that would be an interesting claim to make is if one really did want to include the traditional supernatural baggage — in which case it’s a non-empty claim, but a wrong one.

If you hold some unambiguously non-supernatural position that you are tempted to refer to as “religion” — awe at the majesty of the universe, a conviction that people should be excellent to each other, whatever — resist the temptation! Be honest and clear about what you actually believe, rather than conveying unwanted supernatural overtones. Communication among human beings will be vastly improved, and the world will be a better place.

The other favorite move to make, perhaps not as common, is to mess with the meaning of “science.” Usually it consists of taking some particular religious claim that goes beyond harmless non-supernatural wordmongering — “God exists,” for example, or “Jesus rose from the dead” — and pointing out that science can’t prove it isn’t true. Strictly construed, that’s perfectly correct, but it’s a dramatic misrepresentation of how science works. Science never proves anything. Science doesn’t prove that spacetime is curved, or that species evolved according to natural selection, or that the observable universe is billions of years old. That’s simply not how science works. For some reason, people are willing to pretend that the question “Does God exist?” should be subject to completely different standards of scientific reasoning than any other question.

What science does is put forward hypotheses, and use them to make predictions, and test those predictions against empirical evidence. Then the scientists make judgments about which hypotheses are more likely, given the data. These judgments are notoriously hard to formalize, as Thomas Kuhn argued in great detail, and philosophers of science don’t have anything like a rigorous understanding of how such judgments are made. But that’s only a worry at the most severe levels of rigor; in rough outline, the procedure is pretty clear. Scientists like hypotheses that fit the data, of course, but they also like them to be consistent with other established ideas, to be unambiguous and well-defined, to be wide in scope, and most of all to be simple. The more things an hypothesis can explain on the basis of the fewer pieces of input, the happier scientists are. This kind of procedure never proves anything, but a sufficiently successful hypothesis can be judged so very much better than the alternatives that continued adherence to such an alternative (the Steady State cosmology, Lamarckian evolution, the phlogiston theory of combustion) is scientifically untenable.

Scientifically speaking, the existence of God is an untenable hypothesis. It’s not well-defined, it’s completely unnecessary to fit the data, and it adds unhelpful layers of complexity without any corresponding increase in understanding. Again, this is not an a priori result; the God hypothesis could have fit the data better than the alternatives, and indeed there are still respected religious people who argue that it does. Those people are just wrong, in precisely analogous ways to how people who cling to the Steady State theory are wrong. Fifty years ago, the Steady State model was a reasonable hypothesis; likewise, a couple of millennia ago God was a reasonable hypothesis. But our understanding (and our data) has improved greatly since then, and these are no longer viable models. The same kind of reasoning would hold for belief in miracles, various creation stories, and so on.

I have huge respect for many thoughtful religious people, several of whom I count among the most intelligent people I’ve ever met. I just think they’re incorrect, in precisely the same sense in which I think certain of my thoughtful and intelligent physicist friends are wrong about the arrow of time or the interpretation of quantum mechanics. That doesn’t mean we can’t agree about those issues on which we’re in agreement, or that we can’t go out for drinks after arguing passionately with each other in the context of a civil discussion. But these issues matter; they affect people’s lives, from women who are forced to wear head coverings to gay couples who can’t get married to people in Minnesota who can’t buy cars on Sundays. Religion can never be a purely personal matter; how you think about the fundamental nature of reality necessarily impacts how you behave, and those behaviors are going to affect other people. That’s why it’s important to get it right.