If the assertion, “Science and religion are incompatible,” simply means, “It is highly unreasonable to accept simultaneously the claims of modern science and the claims of traditional Christianity,” then I agree with it. The trouble is that the word “incompatible” is vague. People often take it to mean something like “logically contradictory,” and I do not agree that science and religion are incompatible in that sense.

For this reason I prefer to avoid the language of compatibility/incompatibility, and talk instead about “tensions” between science and traditional faith. When I am feeling ornery I might say, “severe tensions.” This terminology seems more accurate and descriptive to me. Whether or not the tensions can be relieved in some plausible way is something people have to decide for themselves. My own view is that they cannot be so relieved, but obviously a lot of people disagree.

The only way I can see for there to be an actual contradiction between science and religion is if you specifically build into the religion some factual claim about the natural world. If you regard it as essential to your faith that the world not be more than ten thousand years old, then you really do have a contradiction between science and faith. Short of that, however, religion always seems to have enough wiggle room to avoid the charge of outright contradiction. For example, I think the problem of evil provides a strong reason for rejecting traditional theism, but I cannot absolutely rule out the possibility that God needs to permit evil and suffering to achieve some worthy greater good.

A good example of the confusion that compatibility talk can cause comes from the little book Science and Religion: Are They Compatible. It is an exchange of essays between Daniel Dennett and Alvin Plantinga, three each, apparently based on a debate they had at a conference of the American Philosophical Society. Plantinga opens the debate in a promising way, writing:

Our question: Are science and religion compatible? A useful project would be to try to make the question more precise: What is religion? What is science? What is incompatibility, and what varieties does it come in (explicit contradiction, implicit contradiction, contradiction in the presence of plausible assumptions, improbability of their conjunction)?

Yes, that would have been a useful project. Of the possible meanings of “incompatible” on offer I favor the last, but Plantinga mostly addresses himself to the others. Alas, just a few sentences later Plantinga writes, “These are good topics. but they’ll have to wait for another occasion; here I’ll assume that we have at least a rough grasp of the question.” D’oh!

It quickly becomes clear, however, that Plantinga and Dennett are not using the same notion of incompatibility. A major portion of Plantinga’s defense of compatibility is the idea that God is guiding, in the sense of causing, the mutations on which evolution is based. (We have discussed this argument at length recently, here and here.) Science can’t rule this out! Plantinga seems to think his job is mostly done with this trivial observation. Indeed, in his second essay Plantinga writes:

On further thought, though, it struck me it wasn’t really theism [Dennett] was claiming to be silly, but a different proposition: (1) God guided and orchestrated the course of evolution to produce the kind of creatures he wanted. I was arguing that God and evolution are possible, by pointing to another proposition that is clearly possible, and entails both the existence of God and the truth of evolution. That other proposition is (1); and I said that 1 was possible. I wasn’t arguing that (1) was true, but only using it to show that the existence of God is compatible with the current scientific theory of evolution. And (1) can do its job, even if it isn’t true, even if it isn’t plausible, and even if it is silly. All it has to be is possible.

Dennett, for his part, is plainly using a different notion of compatibility. After quoting a lengthy passage from one of his earlier publications, he writes:

So I agree that contemporary evolutionary theory can’t demonstrate the absence of intelligent design, and any biologist who insists that we can is overstating the case. But Plantinga must deal with the implications of one sentence in the passage above: “Prehistoric fiddling by intergalactic visitors with the DNA of earthly species cannot be ruled out, except on grounds that it is an entirely gratuitous fantasy. Now we might draw the debate to a close right here. I could happily concede that anybody who wishes to entertain the fantasy that intelligent designers from another galaxy (or another dimension) fiddled with our evolutionary prehistory, or salted Earth with life forms, or even arranged for the constants of physics to take on their particular “local” values will find their fantasy consistent with contemporary evolutionary biology.

This disagreement over usqge makes the whole debate highly unsatisfying. Plantinga and Dennett are talking at cross purposes. Plantinga seems inordinately concerned with establishing logical compatibility between God and evolution, while Dennett wants to move on to the far more important question of whether any remotely plausible reason can be offered for believing both. After the first exchange of essays, they both mostly just repeat themselves.

There are some other interesting moments in the debate, but I’ll save those for a future post. It turns out our new blogging platform has a word count feature, and suddenly I can just feel myself starting to ramble…