Science, as I have been insisting in this series of blog posts, is a consensus enterprise. Generally accepted scientific ideas are those that have achieved a wide currency by successfully persuading everyone that they are very likely true. Such persuasion takes several forms:
Peer review assures that the most knowledgeable experts will have had a look at the ideas before they were published.
Repeatability assures that other researchers, with slightly—or even significantly—different setups can duplicate the ideas. If your magical, new, I-could-win-a-Nobel-Prize, particle doesn’t show up when the physicists in Moscow duplicate your experiment, then too bad for your new particle and your Nobel Prize.
The vast network of interlocking ideas already in place provides a powerful collective intuition about what sorts of new ideas are most unusual and in need of careful inspection.
Ideas championed by small bands of isolated outsiders should be viewed with suspicion and challenged with a very reasonable question: If these ideas are so compelling, how come so few really knowledgeable scientists accept them? And why are their champions outside the scientific community?
The response to these questions takes one of two forms: If you agree with the ideas being proposed by the outsiders, then you accuse the scientific community of willful ignorance and irrational stubbornness. You cherry-pick history for few examples where scientists were too dismissive of new ideas, or too confident in current ones, or too gullible in the acceptance of things they wished were true. You then present those examples—Piltdown Man, peppered moths, the Miller-Urey experiment—as if they were typical examples of how unreliable the “assured results of modern science” really are. If you disagree with the ideas being posed by the outsiders then you simply note that these ideas come from outside the scientific community and assume that, if they had any merit, they would be inside the community already. After all, science has a wonderful track record of success. Every time you power up your computer, almost all of the physics of the 20th century is stunningly confirmed.
A common strategy employed by outsiders who don’t understand how science works is to highlight how many times the scientific community has had to abandon “assured results of modern science,” as Al Mohler so dismissively labeled scientific consensus in his infamous address on why we need to believe the earth is 10,000 years old. The implication is that, if you wait long enough, the “assured results” of today will also collapse like the “assured results” of yesterday, making room for the ideas that you like better.
If we are perfectly honest, we have to admit that there is truth to this. During every major, and even minor, transition in science there are people who hold to traditional views; there are egregious examples of tenacious, seemingly irrational, loyalty to the status quo. The most famous example would be Albert Einstein, who went to his grave insisting that “God does not play dice with the universe,” when, as we now know, almost every physicist on the planet had been dragged unwillingly by the evidence for quantum mechanics to the unsavory conclusion that God does play dice with the universe. And there are countless other examples. Lord Kelvin wouldn’t accept the emerging evidence for an ancient earth at the end of the 19th century. Galileo wouldn’t accept Kepler’s calculations that showed that the planetary orbits were elliptical, rather than circular. Fred Hoyle wouldn’t accept the evidence for the Big Bang and developed a whole other theory to oppose it, one that seemed less “supernatural.”
There is no simple way, of course, to know when an idea is past its prime and in need of discarding. Such ideas do not start to get mold around the edges like cheese past its prime. We have been told for decades by anti-evolutionists from William Jennings Bryan, to Henry Morris and Ken Ham, to the senior fellows at the Discovery Institute, that evolution is past its prime and needs to be discarded. William Dembski, in his review of Saving Darwin, scolded me for being “loathe to admit that Darwin is passé.” I was wasting my time trying to save poor Darwin, whose coffin was finally ready to be lowered into the ground.
Ideas do have to be discarded from time to time. So how can we tell if evolution is such an idea, now past its prime, and living only on the tenacious life-support it receives from die-hard true believers? Here are some general indications that evolution has been misdiagnosed as terminal by the anti-evolutionists:
The “disagreements” within evolutionary biology are signs of health, not illness. They occur between people who share a significant conviction that evolution is true in general and they are arguing about the particulars. Probably the most famous such debate of the past half-century was Stephen Jay Gould’s endorsement of “punctuated equilibrium” over the more traditional “gradualism” of most other theorists, like Richard Dawkins. This debate was offered as evidence that there was serious dissent with the scientific community about evolution—a preposterous conclusion. This debate was not about evolution at all; it was about the rate at which evolution occurs. Gould thought that evolution sped up and slowed down to a much greater degree than many of his peers. This is no more a debate about evolution than Mohler’s disagreement with BioLogos about how to read Genesis is part of a debate about the existence of God. The lesson here is to be careful to distinguish between a minor debate over a detail, and a major debate over a theory.
If the explanatory territory of a theory is growing, the theory is in great shape. And we know from the explosive mapping of genomes, and other developments that more and more territory is coming under the explanatory umbrella of evolution. This evidence mounts daily.
When theories get shaky, senior scientists with established reputations will step forward and articulate the concerns. This is a “statesmanlike” role that leaders in the scientific community take seriously. In the late 1980s there were some unresolved issues with the Big Bang theory and a leading cosmologist wrote an editorial in Scientific American calling attention to the issue and warning that if new data did not rescue the theory, it could collapse. Fortunately, the new data showed up on cue and the Big Bang survived. If there were wholesale problems with evolution, there would be senior evolutionists stepping forward and highlighting the problem. And they are not.
In the final analysis, there is no simple way, at a moment in time, to evaluate the exact strength and staying power of a theory. But there are ways to evaluate the claims that a theory is collapsing and none of the claims that evolution is collapsing can withstand that scrutiny.