Consider The Grand Evolutionary Myth (GEM). According to this story, organic life somehow arose from nonliving matter by way of purely natural means and by virtue of the workings of the fundamental regularities of physics and chemistry. Once life began, all the vast profusion of contemporary flora and fauna arose from those early ancestors by way of common descent. The enormous contemporary variety of life arose through such processes as natural selection operating on such sources of genetic variability as random genetic mutation, genetic drift and the like. I call this story a myth not because I do not believe it (although I do not believe it) but because it plays a certain kind of quasi-religious role in contemporary culture: it is a shared way of understanding ourselves at the deep level of religion, a deep interpretation of ourselves to ourselves, a way of telling us why we are here, where we come from, and where we are going.
Now it is certainly possible—epistemically possible, anyway, —that GEM is true; God could have done things in this way. Certain parts of this story, however, are to say the least epistemically shaky. For example, we hardly have so much as decent hints as to how life could have arisen from inorganic matter just by way of the regularities known to physics and chemistry. (Darwin found this question deeply troubling; at present the problem is vastly more difficult than it was in Darwin’s day, now that some of the stunning complexity of even the simplest forms of life has been revealed.) No doubt God could have done things that way if he had chosen to; but at present it looks as if he didn’t choose to.
So suppose we separate off this thesis about the origin of life. Suppose we use the term ‘evolution’ to denote the much weaker claim that all contemporary forms of life are genealogically related. According to this claim, you and the flowers in your garden share common ancestors, though we may have to go back quite a ways to find them. (So perhaps herbicide is a sort of fratricide.) Many contemporary experts and spokespersons—Francisco Ayala, Richard Dawkins, Stephen Gould, William Provine, and Philip Spieth, for example—unite in declaring that evolution is no mere theory, but established fact. According to them, this story is not just a virtual certainty, but a real certainty. This is as solid and firmly established, they say, as that the earth is round and revolves around the sun. (All of those I mentioned explicitly make the comparison with that astronomical fact.) Not only is it declared to be wholly certain; if you venture to suggest that it isn’t absolutely certain, if you raise doubts or call it into question, or are less than certain about it, you are likely to be howled down; you will probably be declared an ignorant fundamentalist obscurantist or worse. In fact, this isn’t merely probable ; you have already been so-called: in a recent review in the New York Times , Richard Dawkins, an Oxford biologist of impeccable credentials, claims that “It is absolutely safe to say that if you meet someone who claims nor to believe in evolution, that person is ignorant, stupid or insane (or wicked, but I’d rather not consider that).” (Dawkins indulgently adds that “You are probably not stupid, insane or wicked, and ignorance is not a crime . . .”)
Now what is the source of these strident declarations of certainty, these animadversions on the character or sanity of those who think otherwise? Given the spotty character of the evidence—a fossil record displaying sudden appearance and subsequent stasis and few if any genuine examples of macroevolution—these claims of certainty seem at best wildly excessive. From a Christian perspective, evolution isn’t remotely as certain as all that. Take as evidence what the Christian knows as a Christian together with the scientific evidence—the fossil evidence, the experimental evidence, and the like: it is at best absurd exaggeration to say that, relative to that evidence, evolution is as certain as that the earth is round. The theist knows that God created the heavens and the earth and all that they contain; she knows, therefore, that in one way or another God has created all the vast diversity of contemporary plant and animal life. But of course she isn’t thereby committed to any particular way in which God did this. He could have done it by broadly evolutionary means; but on the other hand he could have done it in some totally different way. For example, he could have done it by directly creating certain kinds of creatures—human beings, or bacteria, or for that matter sparrows and houseflies—as many Christians over the centuries have thought. Alternatively, he could have done it the way Augustine suggests: by implanting, seeds, potentialities of various kinds in the world, so that the various kinds of creatures would later arise, although not by way of genealogical interrelatedness. Both of these suggestions are incompatible with the evolutionary story. And given theism and the evidence it is absurd to say that evolution (understood as above) is a rockribbed certainty, so that only a fool or a knave could reject it.
So why that insistence on certainty and the refusal to tolerate any dissent? The answer can be seen, I think, when we realize that what you properly think about these claims of certainty depends in part on how you think about theism. If you reject theism in favor of naturalism, this evolutionary story is the only visible answer to the question, “Where did all this enormous variety of flora and fauna come from? How did it get here?” Even if the fossil record is at best spotty and at worst disconfirming, even if there are anomalies of other sorts, this story is the only answer on offer (from a naturalistic perspective) to these questions; so objections will not be brooked.
A Christian, therefore, has a certain freedom denied her naturalist counterpart: she can follow the evidence where it leads.
On Christian Scholarship, Alvin Plantinga