Science has failed to prove evolution. I hear this all the time from creationists. And they are absolutely right. But not for the reasons they claim. The fact that science has not proved the truth of evolution has nothing to do with the quality of scientific inquiry. Rather it has to do with the nature and objectives of that inquiry.
Put simply, the goal of science is not to prove the truth of theories or propositions. Proof is the province of mathematics and formal logic, not science. We have proved, for example, that the square of the length of the hypotenuse of a right triangle is equal to the sum of the squares of the lengths of the two other sides (Pythagorean theorem). Moreover, we can say with logical certainty that if all men are mortal and if Socrates is a man, then Socrates is mortal. But we cannot say that we have proved the truth of any scientific proposition about the nature of the world, whether it concerns physics, chemistry, cosmology, geology, or evolution.
So what is the point of science if it is not about proving things? In short, science is about creating models, or explanations, to describe the world and to devise ways to test those models. If a model is a good one, it will fit the available evidence and, importantly, will suggest hypotheses that can be objectively tested to further support or to refute the model. If the latter, then scientists will strive either to modify or refine the model or to discard it in favor of a new model that is consistent with all of the evidence. And that model, in turn, is to be tested through further observations and research. And so it goes.
And what is the point of creating, testing, and refining models? Such models, to the extent they are successful, represent our best approximation of the nature of the world and how it works. The better the model, the more explanatory and predictive power it has and the closer we can say we have come to a true understanding of the world. More importantly, the better the model’s predictive power, the more power we have for dealing with the world.
So when someone argues that science has not proved evolution, you can agree but then reply that that is because the scientific community doesn’t claim to have proved evolution. Rather, evolutionary scientists are simply saying that their model is the best fit for the observational and experimental evidence. And because of that the evolutionary model is more likely to be closer to the truth than previous or competing models, such as the creationist one, which, frankly, doesn’t remotely fit the evidence.
After all, there was a time when the flat earth model and the geocentric solar system model were “cutting edge” descriptions of our understanding of the world. But of course no one (except perhaps a few crazies) argues for those models any longer. It’s time to do the same with the creationist model.
© 2014 John M. Phillips