When two groups of experts disagree about a controversial subject that intersects the public school curriculum students should learn about both perspectives. In such cases teachers should not teach as true only one competing view, just the Republican or Democratic view of the New Deal in a history class, for example. Instead, teachers should describe competing views to students and explain the arguments for and against these views as made by their chief proponents. —http://www.discovery.org/a/1134

Doubt is our product since it is the best means of competing with the “body of fact” that exists in the mind of the general public. It is also the means of establishing a controversy. Within the business we recognise that a controversy exists. However, with the general public the consensus is that cigarettes are in some way harmful to the health. If we are successful in establishing a controversy at the public level, then there is an opportunity to put across the real facts about smoking and health. —Brown & Williamson Tobacco Corp., 1969 (source)

“Teaching the controversy” has always been a rhetorical centerpiece of the intelligent-design movement, but it has become a more prominent part of their strategy in the wake of ID’s 2005 court defeat in Dover, Pennsylvania. Seeking to avoid blame for the Dover verdict, creationist groups such as the Discovery Institute pleaded that they had never wanted to teach intelligent design per se, but only the “evidence for and against” evolution.

The most sinister part of this argument is its apparent fairness. Who could object to teaching students all sides in a dispute? Hardly anyone, of course, which is why ID advocates sometimes trumpet polls showing that large majorities say students should be taught the evidence for and against evolution. That shouldn’t be a surprise: if there were legitimate evidence against evolution, even I would certainly want it to be taught, as I think most atheists would. But the problem is that these polls ask a loaded question by assuming that there is such evidence.

If there is a legitimate, scientific controversy over some issue, then by all means, teachers should present all sides in a fair and even-handed manner. However, this is not a description which applies to the teaching of evolution. Creationists and their intelligent-design comrades have steadfastly avoided making their case to the scientific community (where it meets with near-unanimous scorn). Instead, they’re attempting to do an end-run around that scrutiny by forcing their beliefs into public schools before they have won the approval of practicing, qualified scientists in those fields. This is completely backwards from how these controversies are supposed to be resolved.

The problem with “teaching all sides” is that it can give fringe ideas a credibility they have not earned. Excessive concern for “balance” leads to presenting the speculations of cranks and crackpots as if they were on equal footing with the positions defended by vast majorities of qualified experts. (The media has a similar problem.) And this is very useful to advocates of pseudoscience, who often do not need to win the rhetorical battle outright; they can triumph merely by muddying the waters and preventing a consensus from forming around the truth. This is the same strategy employed by tobacco companies, as we can see from the second excerpt above, as well as by oil companies seeking to forestall regulation of greenhouse gas emissions.

But with all that said, the idea of teaching the controversy isn’t an intrinsically bad one. There are plenty of subjects that have legitimate controversies where this commendable call for fairness could be better applied.

For example, how about sex ed? A great many religious conservatives – many of the same ones who call for teaching the controversy on evolution, I don’t doubt – change their tune when it comes to public-school health classes, demanding that students be taught an “abstinence-only” program that omits contraception, or mentions it only to discuss its failure rates. How strange. Whatever happened to fairness? Whatever happened to learning about all sides? Why can students make up their own minds about evolution, but not about how to protect themselves from STDs?

Better yet, how about the public schools that teach about the Bible? (There are plenty that do, using curricula developed by third parties such as the Bible Literacy Project or the National Council on Bible Curriculum in Public Schools.) Here, surely, is a topic that’s ripe for teaching the controversy! Let’s have students read selections from The God Delusion or Losing Faith in Faith. Let’s have students hear criticisms of the Bible, like Richard Dawkins’ famous statement that the god of the Old Testament is “arguably the most unpleasant character in all fiction… a misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously malevolent bully” – and then let’s show them the verses that he uses to back up that criticism! To borrow some terminology from ID advocates, shouldn’t the “strengths and weaknesses” of the Bible be “critically analyzed”?