Education Icon Education
Free Speech Icon Free Speech
Intelligent Design Icon Intelligent Design

Response to Barbara Forrest’s Kitzmiller Account Part VII: Exposing the “Correlation = Causation” Fallacy

[Editor’s Note: A single article combining all ten installments of this response to Barbara Forrest can be found here, at “Response to Barbara Forrest’s Kitzmiller Account.” The individual installments may be seen here: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9, Part 10.]

According to Wikipedia, a classic example of the “Correlation implies causation” logical fallacy might assert, “Sleeping with one’s shoes on is strongly correlated with waking up with a headache. Therefore, sleeping with one’s shoes on causes headache.” The way to refute this argument is to point out that it is based upon a logical fallacy which proves causation via correlation, and explain how a third explanation better accounts for the observed data than the mere “correlation.” As Wikipedia suggests, “A more plausible explanation is that both are caused by a third factor, in this case alcohol intoxication, which thereby gives rise to a correlation.” If the person arguing this logical fallacy still is not convinced, one can simply find people who slept with their shoes on and didn’t wake up with headaches. This is the same correction I provide to analyze Barbara Forrest’s rhetoric and expose the logical fallacy of her “correlation equals causation” arguments in her Kitzmiller account.

Philosopher Barbara Forrest uses “correlation = causation” arguments prolifically. In her Kitzmiller response she argued that because (1) five years ago, William Dembski apparently used the phrase “Internet stalkers” in reference to Wesley Elsberry and Richard Wein, and (2) Discovery Institute (DI) apparently called Dr. Forrest a “conspiracy theorist” in a response to her book, that when (3) Thomas More Legal Center (TMLC) wrote a brief using the words “stalker” and “conspiracy theorist,” this proved DI helped TMLC write the brief. She therefore asserts a “correlation = causation” argument regarding a motion made by TMLC before the trial to exclude her as an expert witness:

DI and TMLC had apparently overcome their differences long enough to collaborate on the accompanying brief because it contained clear evidence of DI’s input. Although I was not called as a scientific expert, the defense argued that I should be excluded because I had no scientific expertise and because I am, in their words, “little more than a conspiracy theorist and a web-surfing, ‘cyber-stalker’ of the Discovery Institute . . . and its supporters and allies.”

People who overuse “correlation = causation” arguments are sometimes called conspiracy theorists. Dr. Forrest should therefore realize that (1) different groups might independently observe that she overuses “correlation = causation” arguments in conspiracy theorist fashion, and (2) the fact is that Discovery Institute gave absolutely zero input on this brief from TMLC.

This episode illustrates the bankruptcy of Barbara Forrest’s “correlation = causation” arguments. Her arguments that the religious affiliations of ID-proponents make ID religious are similarly fallacious and bankrupt. According to Dr. Forrest, if there’s a correlation between ID proponents and religion, then religion must be the only thing causing ID. Her arguments have already been logically refuted in earlier parts of this ten-part response-series, showing that religious beliefs of ID-proponents don’t matter when assessing whether ID is science (Part II and Part III) and that motives of ID-proponents don’t matter (Part IV) when assessing whether ID is science.

When assessing whether a given claim is scientific, all that matters is that an empirically-based scientific methodology of knowing is given to back the claim. Alleging that a claim is religious and unscientific because of (a) the larger philosophical implications of the claim, (b) the religious beliefs of the claimant, (c) the motives of the claimant, or (d) some historical relationship between certain types of religious persons and that claim uses an irrelevant argument. Evolutionists should consider this carefully because intelligent design and evolution are methodologically equivalent: Any argument invoking (a) through (d) to disqualify intelligent design from being science would similarly disqualify evolution from being science, if the facts and the argument were applied fairly.

But if Barbara Forrest still isn’t convinced, a clearer way to refute her argument may be to ask, “What religious reason did the atheist Antony Flew have to say, ‘[i]t now seems to me that the findings of more than fifty years of DNA research have provided materials for a new and enormously powerful argument to design’?” The answer is none, because intelligent design is an empirical argument that anyone can take seriously regardless of their religious beliefs. This demonstrates adherence to intelligent design without any correlation to religion, unambiguously refuting her argument. The actual cause for support of intelligent design must therefore be something other than mere religion: the cause is the scientific data of biological complexity.

Sadly, Dr. Forrest’s “correlation = causation” arguments were foundational to the plaintiffs’ case in Kitzmiller. Not only did they use her arguments about the religious beliefs of ID-proponents, but in one egregious instance, plaintiffs attacked Scott Minnich during cross-examination because a diagram from a creationist publication had long ago made arguments about the unevolvability of the bacterial flagellum, and also contained a flagellum diagram similar to the one Minnich used in court. Minnich simply replied that he’d never seen the creationist publication, and explained where he got his diagram: “Right, and again this [my diagram] is, this picture is out of a biochemistry textbook, Voet and Voet.” Thus, I reported:

Voet and Voet of course is a widely used secular textbook in biochemistry. So, if the plaintiffs’ insinuations have any constitutional meaning then the implication that if a creationist document says something, and then you say the same thing, then what you have said is therefore religious and unconstitutional. Teachers who use Voet and Voet should watch out for the ACLU — you might be next!

These fallacious “correlation = causation” arguments need to be put to rest, so that the teaching of evolution and other science, like Voet and Voet, does not come under threat.

Casey Luskin

Associate Director and Senior Fellow, Center for Science and Culture
Casey Luskin is a geologist and an attorney with graduate degrees in science and law, giving him expertise in both the scientific and legal dimensions of the debate over evolution. He earned his PhD in Geology from the University of Johannesburg, and BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at both the graduate and undergraduate levels. His law degree is from the University of San Diego, where he focused his studies on First Amendment law, education law, and environmental law.



__editedBarbara ForrestKitzmiller v. Dover Area School District