In the case of Newton's theory, the orbit of the moon provided solid evidence for the theory and the orbit of Saturn provided evidence against it. But, as the astronomers at the time saw clearly, the evidence from the moon deserved to be weighted more heavily—it deserved, in some sense, more votes. If 17th-century "antigravitationists"—the French astronomers desperately hoping René Descartes would win the international competition for most brilliant scientist—had demanded that people either explain the Saturnian anomaly or reject Newton's theory, they would be much like the anti-evolutionists of today. This is why I think history of science is so important in these discussions; we have seen all these arguments before and should be cautious when long dead arguments arise from their crypts and sneak back into the discussion.

To evaluate the significance of anomalies requires subtle judgments by experts. Only someone who can actually perform gravitational calculations can adequately appreciate the significance of how Newton's theory predicts that the planets travel in elliptical orbits. It is breathtakingly beautiful to see how this works. It is equally easy to understand why people who appreciate this are unlikely to abandon such a theory because of small discrepancies in the orbit of Saturn. Their intuition tells them that there must be some other explanation for the anomaly, even though they have no idea what that might be.

Scientists' unwillingness to be persuaded by anomalies may look like pigheadedness. A lawyer could make such apparently blind allegiance to a theory in the face of counterevidence seem irrational and suggestive of a conspiracy to protect a failing theory. But there is a collective wisdom in the scientific community that I don't think Bill appreciates. The experience of the scientific community when it comes to evolution is that countless anomalies from the time of Darwin down to the present have been happily resolved, just as the irregularity in the orbit of Saturn was resolved with the discovery of Uranus. I trust this collective judgment. Bill does not: "Giberson and Collins' constant drumming of mainstream and consensus science is beside the point—science progresses by diverging from the mainstream and by breaking with consensus."

The collective wisdom of "mainstream and consensus science" is most certainly not "beside the point." It is precisely the point. I think Bill is just wrong when he says that science progresses by "breaking with consensus." This widespread misperception comes from conflating "revolutionary" science with "normal" science, to use Thomas Kuhn's terms. Revolutionary science is exciting and makes the history books; it is easy to remember. Famous scientists—Newton, Darwin, Einstein—are "revolutionaries" to be sure, but most scientific progress occurs by steadily expanding our knowledge, not blowing it all up and starting over. We need think only of the rapid progress in cosmology in the 20th century to see this clearly. Einstein inaugurated a revolution with his theory of General Relativity in the first couple of decades but, after the dust settled on that, there was steady progress for eighty years.

Anti-evolutionists need to undermine the concept of "scientific orthodoxy." And they have succeeded in convincing many evangelicals that it represents nothing more than the unsupported collective opinion of scientists who are basically just "voting" on things. Going against this orthodoxy, as the anti-evolutionists have to do needs to appear courageous and revolutionary, not eccentric and uninformed.