Truth vs fairness
The Guardian has a good essay by Richard Dawkins of Oxford and Jerry Coyne of the University of Chicago on the debate over teaching Intelligent Design in schools:
The call for balance, by the way, was always tempered by the maxim, "When two opposite points of view are expressed with equal intensity, the truth does not necessarily lie exactly half way between. It is possible for one side simply to be wrong."Dawkins and Coyne may be writing about the Intelligent Design controversy, but the general point they make is a good one: just because two opposite points of view exist does not mean the truth must necessarily lie in between, even if in many cases it does, and to think so is fallacious.
Why, then, would two lifelong educators and passionate advocates of the "both sides" style of teaching join with essentially all biologists in making an exception of the alleged controversy between creation and evolution? What is wrong with the apparently sweet reasonableness of "it is only fair to teach both sides"? The answer is simple. This is not a scientific controversy at all.