Both in my classrooms and in public forums, I have seen most discussions of the relative merits of evolution and creationism falter due to confusion over use of the terms theory and fact. Creationists try to challenge the validity of evolution by asserting that it is merely a theory, while evolutionists counter by asserting that evolution is plainly a fact. This creates an impasse; because the terms are presumed to be mutually exclusive, there is no semantic space in which to reconcile them. No progress is made, either in persuading the persuadable or improving the ability of evolutionists to engage in constructive dialogue with those who discount or dismiss evolution.
I recommend a more productive and, in my view, more accurate expression to describe evolution: namely, evolution is the best explanation for the diversity of life forms on Earth, including humans, and for the deep connections that exist among all terrestrial life.
My principle method in approaching extraordinary claims is rhetorical and operates on two fronts. First, it concerns the ways in which discourse advancing extraordinary claims appeals to various audiences. I have found one of the best ways to promote skepticism is to reveal the rhetorical strategies (and attendant sophistries) that are used in paranormal and pseudoscientific discourse. While people are generally resistant to being “wrong,” they are considerably less defensive about being “fooled” (Marston 2014). Second, it seeks to develop more effective and constructive rhetorical strategies that may be employed by skeptics in their efforts to convert the credulous. My comments here are rooted in this second front.
Facts
Facts are, of course, statements that are true. They are typically beyond dispute and therefore noncontroversial. To establish a disputed statement as a fact in any discussion requires clear evidentiary demonstration. To be productive in dialogue, however, such evidentiary demonstration must secure the adherence of all interlocutors. Indeed, unilaterally asserting a statement as a fact is counterproductive and ends discussion, disqualifying those who dispute the fact as recalcitrant. For this reason alone, it is not rhetorically effective to claim that evolution is a fact when engaging creationists or seeking to persuade those who attend such debates and discussions. This is especially true for young people encountering tension between what is taught in their biology classes and what is preached in their homes.
Asserting evolution as a fact is rhetorically problematic, because while facts are true statements, that is not the only feature of a fact (thus, not all true statements are best characterized as facts). Belgian philosopher Chaïm Perelman (1969) notes that facts are atomistic and immutable. That is, inferences based upon facts may change, and new facts may be discovered, but the facts themselves do not change. So, examples of facts might be statements such as “The Green Bay Packers won the 1967 Super Bowl,” “My father passed away of a heart attack,” “The Bill of Rights was ratified in 1791,” and so on. From this perspective, I find that asserting evolution as a fact exposes an advocate to critique based upon the many advances and refinements in evolutionary theory over the past two hundred years, for evolutionary theory is by no means immutable—it is a remarkably dynamic and robust area of scientific research. Now, advocates of evolution may object that when they assert that evolution is a fact, they are not asserting that evolutionary theory is a fact but rather that the biological phenomenon is a fact. Fair enough, but when discussing evolution, it is virtually impossible to avoid this equivocation between the biological phenomenon and the theories that seek to explain it. It may therefore be best to sidestep the issue by avoiding the F-word.
Theories
Theories are sets of concepts held together by explanatory relationships. It is fair to say that, in a sense, evolution is a theory and, judging by the titles of countless books written by biologists on the subject, this characterization is not hostile to evolutionists. Of course, creationists add the modifier mere, either explicitly or tacitly (by contrasting theories with facts), and this is patently unfair. However, responding to the claim that evolution is not a mere theory by claiming evolution is a plain fact reinforces—even if unintentionally—this specious bifurcation and risks incoherence, if indeed it is sensible to describe evolution as a theory. (Again, we see the rhetorical effects of the nearly intractable equivocation I referenced in the previous paragraph.)
Even if we were successfully able, in discussions with creationists, to tease out the ways in which evolution is a theory and the ways in which it is a fact, we would still have moved the argument into territory that is likely too sophisticated and subtle for lay audiences: namely, the distinction between “mere” theories and established theories. To demonstrate that evolution is the latter and not the former simply does not redress the critique that evolution is still a theory, leaving in the minds of nearly all creationists―and a fair proportion of other lay people―the impression that evolution is somehow less than “true,” at least in the sense that facts are true.
Best Explanations
For these reasons, I suggest that evolutionists simply step away from the whole tangle of the fact-versus-theory debate, by presenting evolution as the best explanation for the development of life on Earth, including the emergence of humans. “Best explanations” need not face the critiques that disputed “facts” typically do and that characteristically render dialogue and debate unproductive. Presenting evolution as our best explanation both diffuses such critiques and relieves advocates of evolution of a burden of proof that is, frankly, of little relevance to the debate. Indeed, evolutionists are best served by directing attention precisely to the central question: Which better accounts for the diversity of life and the development of species—evolution or creationism?
Note that in some areas of skeptical inquiry, this view of facts, theories, and best explanations is well established. Joe Nickell, in his many Skeptical Inquirer columns, is especially disciplined in offering his conclusions as best explanations (e.g., positing bears as the most likely object in Bigfoot sightings or hypnagogia as our best explanation for many ghost “sightings”). But in other areas, the problem I describe here arises in a very similar manner, most notably in the issue of climate change, which is generally characterized by a struggle over “facts” and “theories.” The better armed skeptics are rhetorically, the more effective they will be.
References
Marston, Peter J. 2014. The rhetoric of extraordinary claim. Skeptical Inquirer 38(5): 50–54.
Perelman, Chaïm. 1969. The New Rhetoric. Notre Dame, IN: University of Notre Dame Press.
Related Article
David Morrison, “Only a Theory? Reframing the Evolution/Creation Issue.” Skeptical Inquirer, November/December 2005. Online at skepticalinquirer.org and reprinted in K. Frazier, ed., Science Under Siege, Prometheus Books 2009.