In a recent online discussion about whether intelligent design creationism should be taught as part of science, one of the participants took exception to a statement by someone else that the theory of evolution is so well established that it was of no use to allow for the inclusion of intelligent design creationism. The challenger asked, quite reasonably: “On what things is there no room for debate? Of what things are we so certain that we’re willing to close the door to possibilities? If academics allow themselves to appear dogmatic about their theories, we legitimize dogmatism. We should be careful that scientists themselves do not become the new proselytizers to claim they hold absolute truth.”

This puzzlement is not uncommon and not unjustified. Seen from the outside, scientists must seem as if we either cannot make up our minds as to what we know for certain and what we are unsure of, or we are accused of cynically shifting our position for polemical advantage, sometimes arguing that evolution is a fact beyond dispute (in order to exclude intelligent design creationism as a viable competitor) while also asserting that intelligent design creationism is not scientific because it is not falsifiable. On the surface, those two positions seem inconsistent, applying different criteria to the two theories.
It is true that scientists assert that “evolution is a fact,” just as they assert that “gravity is a fact.” They also acknowledge the “theory” of evolution and the “theory” of gravity. And they also assert that ALL knowledge is provisional and subject to change.

How can all these things be simultaneously true? How can something be at the same time a fact and a theory, certain and yet subject to change? These are deep questions and ones that can lead to heated discussions since they affect deeply held core beliefs about science and religion.

These also happen to be questions that form the core of the seminar course I teach to sophomores. We discuss all kinds of things in my course including science and religion, intelligent design etc. and it is remarkable that in the four years that I have taught it, there have been absolutely no blowups or confrontations or unpleasantness, although colleagues have told me that these very same questions have caused problems in their classes. The relative harmony of my class exists despite the fact that I know that many of my students are quite religious, from a variety of traditions, and they know that I am an atheist. These personal beliefs are not things that we keep secret because they shed important perspectives on the discussions.

Perhaps the reason for the lack of friction is that my course starts with looking closely at what science’s knowledge structure is. We read Pierre Duhem, Karl Popper, Thomas Kuhn, Imre Lakatos, Larry Laudan and other historians and philosophers of science and see how it is that science, unlike other areas of knowledge, progresses rapidly because of the commitment of its practitioners to a paradigm in which the framework in which problems are posed and solved are well defined. The paradigm consists of a scientific consensus about which theory (or a set of closely related theories) should be used for analyzing a problem, rules for determining what kinds of research problems are appropriate, the kinds of evidence, arguments, and reasoning that are valid, and the conditions that solutions to these research problems must satisfy if they are deemed to be satisfactory. That complex paradigmatic framework is sometimes loosely and collectively referred to as a “theory” and students quickly realize that the popular meaning of the word “theory” as some sort of simple hypothesis or guess does not apply in the scientific realm.

As long as that paradigmatic framework (or “theory”) is fruitful and brings forth new problems and successes, it remains inviolate from challenges, and practitioners strenuously resist attempts at overthrowing it. The “theory” is thus treated and defended as if it were a “fact” and it is this that is perceived by some outside of science as dogmatism and an unwillingness to change.

But as Kuhn so persuasively argues, it is this very commitment to a paradigm that is the reason for science’s amazing success, because the scientist working on a problem defined within a paradigm can be assured a priori that it is legitimate and important, and that only skill and ingenuity stands between her and the solution. Solving such problems within a paradigm is a sign of superior skill and brings rewards to the scientist who achieves it. Such conditions ensure that scientists will persevere in the face of challenges and adversity, and it is this kind of dogged determination that has resulted in the scientific breakthroughs from which we now benefit.

Kuhn likens this commitment of scientists to a paradigm to that of an industrialist to the manufacturing process that exists to make a particular product. As long as the product is made well, the manufacturer is not going to retool the factory because of the enormous effort and costs involved. Similarly, learning how to successfully exploit a scientific paradigm involves a long period of scientific apprenticeship in a discipline and scientists are unlikely to replace a working paradigm with another one without a very good reason. Learning to work well within a new paradigm is as costly as retooling a factory, and one does not do so cavalierly but only if one is forced into it. The dogmatism of science is thus pragmatic and not ideological.

But we do know that scientific revolutions, both major and minor, occur periodically. Very few of our current paradigms have a long history. So how and why do scientific paradigms change? They occur when the dominant paradigm shows signs of losing its fruitfulness, when it fails to generate interesting new problems or runs out of gas in providing solutions. It is almost never the case that one (or even a few) unsolved problems result in its overthrow because all scientific paradigms at all times have had many unsolved problems. A few counterexamples by themselves are never sufficient to overthrow a paradigm, though they can be a contributing factor. This is the fundamental error that advocates of intelligent design creationism (IDC) make when they argue that just because evolution by natural selection has not as yet explained some phenomena, Darwin’s theory must be rejected.

To be taken seriously, a new paradigm must also promise to be more fruitful than its predecessor, open up new areas of research, and promise new and interesting problems for scientists to work on. It does that by postulating naturalistic mechanisms that make predictions that can be tested. If it can do so and the predictions turn out to be successful, the commitment to the existing paradigm can be undermined, and the process begins by which the paradigm may be eventually overthrown. IDC has never come even close to meeting this requirement.

Some people have challenged the idea that scientific theories have to have as necessary conditions that they be naturalistic and predictive, arguing that insisting they be so is to impose dogmatic methodological rules. But the requirement that scientific theories be naturalistic and predictive are not ad-hoc rules imposed from outside. They follow as a consequence of needing the paradigm to be able to generate new research programs. How could it be otherwise?

This is why IDC, by pointing to a few supposedly unsolved problems in evolutionary theory, has not been able to convince the biology community of the need to change the way they look at things. Intelligent design creationism does not provide mechanisms and it does not make predictions and has not been able to produce new research.

When we discuss things in the light of the history of science, the students in my class understand why science does things the way it does, why it determinedly holds on to some theories while being willing to abandon others, and that this process has nothing to do with dogma in the traditional religious sense. Religious dogma consists of a commitment to an unchanging core set of beliefs. Scientific “dogma” (i.e. strong commitment to a paradigm and resistance to change) is always provisional and can under the right conditions be replaced by an equally strong commitment to a new “dogma.”

Almost all my students are religious in various ways, and while some find the idea of IDC appealing, they seem to have little difficulty understanding that its inability to enter the world of science is not a question of it being right or wrong, but is because of the nature of science and the nature of IDC. IDC simply does not fit into the kind of framework required to be a fruitful scientific theory.