A reader writes:

How odd that you would call attention to Michael Shermer's open letter now, given the excellent article in the current Atlantic, "Does the Vaccine Matter?" The logical fallacy of the letter is obvious. Just because evolution is the cornerstone of biological science does not mean that any particular vaccine is effective, safe, or worth the risk. Those are empirical questions to be answered experimentally. Good research often results in medical discoveries that look good in theory but fail in practice. The idea that no one should doubt the worth of the flu vaccine if they believe in evolution is comical. If most scientists felt the same way, the creationists would be right to call science an ideology.
There is irony in Shermer's point about herd immunity. He complains that if enough people forgo vaccination, an otherwise avoidable disease can spread. That's only true if the vaccination works, so it begs the question. But the point that any biologist would understand is that natural selection often rewards free-riders as long as the gene responsible for it remains rare. Someone who reasons like a moral human being wouldn't refuse to share in the risk of immunization, but someone who reasons like a selfish gene might. Bill Maher may understand natural selection perfectly.

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