In the famous debate between Bill Nye and Ken Ham (see here for my opinion on this debate), Ken Ham used as his most basic argument the difference between what he called “historical science” and “observational science.” This sort of argument is not new. The more fundamentalist Creationists have maintained the party line that what they call “historical science” is inherently unreliable, that we can’t know anything about the past, and so on.
Recognizing that everyone has presuppositions that shape the way they interpret the evidence is an important step in realizing that historical science is not equal to operational science. Because no one was there to witness the past (except God), we must interpret it based on a set of starting assumptions. Creationists and evolutionists have the same evidence; they just interpret it within a different framework. Evolution denies the role of God in the universe, and creation accepts His eyewitness account—the Bible—as the foundation for arriving at a correct understanding of the universe.
You may notice that this is similar to another dichotomous reframing which has been propagated by Creationist organizations: the one between “microevolution” and “macroevolution,” where “microevolution” happens and “macroevolution” cannot happen and is a false “interpretation” of the data.
This “historical science” business is another minor distinction made by scientists that got blown up into a whole system of thought by Creationists. Yes, there is such a thing as “historical science,” but it designates a difference in the type of evidence used, nothing more (incidentally, evolution does not qualify as “historical science” because we do have direct experimental data about it). It does not imply that “historical science” is bogus because “no one was there to witness the past.”
This is expressed even more simply by Ken Ham by telling children to scream to their teachers “were you there?” if they ever bring up evolution. I assume this is supposed to accomplish something, although I have no idea what. Perhaps it is supposed to instill some doubt in the stupider science teachers.
We can also see some connection with presuppositionalist argumentation, in that both try to reduce secular reasoning to the status of assumptions and presuppositions, and then propose God as the ultimate answer.
As in presuppositionalism, the fundamental premise of the false dichotomy is correct: it is true that we interpret the past “based on a set of starting assumptions.” But what they don’t (want to) understand is that everything is interpreted “based on a set of starting assumptions,” not just the past, and Christian fundamentalists have no problem at all reframing the “observational”/ “operational” in terms of their theological assumptions. So the distinction is a dishonest one on the Christians’ part.
On the topic of evolution specifically, Creationists have no problem twisting observational results about evolution to suit their own beliefs (for a specific recent example, see the Lenski experiment; for a more general overview, see the Eye on the ICR blog). During the debate, Ken Ham had no problem arguing against direct observations such as tree rings, fossils, and so on and so forth.
He claimed that his basis for doing so was because we have no evidence that the laws of nature remained the same in past centuries. Bill Nye rightly pointed out that this an extraordinary claim and that it has the burden of proof. But more importantly, it flies in the face of the presuppositionalist boast that the uniformity of natural law can only be explained by the existence of God.
Either science is effective because God ordains the unchanging laws of nature, or science is ineffective at “historical science” because the laws of nature change all the time. Both of these claims cannot be true, and Christians evade the issue by equivocating between “historical science” and “observation science.” They use the success of physics and chemistry to “prove” that God backs the scientific endeavor, and then they use the supposed failures of evolution to “prove” that we should believe God instead of science.
The further issue with the reasoning presented to us by the Creationists talk as if believing in God is some kind of axiom which their opponents simply reject for no good reason.
One problem is that there are plenty of Christians who accept God’s “eyewitness account” (a rather odd term for something that doesn’t have eyes) and yet also believe in evolution. This fact alone destroys the Creationist argument I’ve quoted above.
But the most important problem is that rejection of God’s “eyewitness account” is not an unjustified assumption. The Creationist wants you to first believe that “accepting God’s eyewitness account” and “denying the role of God in the universe” are the same kind of proposition, and then to believe that “accepting God’s eyewitness account” is better than “denying the role of God in the universe.”
But this surely can’t be right: “accepting God’s eyewitness account” is far less parsimonious than the alternative, and therefore requires evidence of God’s existence at the very least. “Denying the role of God in the universe” should be the default assertion, and all others should be rejected. They are therefore not of the same kind at all.
Therefore the statement that “Creationists and evolutionists have the same evidence” is in fact an admission of defeat. To hold a valid belief in Creationist would require additional evidence than holding the default. Absence of such additional evidence means that Creationism cannot in any way be a valid belief.