Science and Logic

Michael Shermer notes, in his essay for Scientific American entitled "Folk Science," that our intuition of causes is often wrong. "To discriminate true causal inferences from false," he writes, "real science trumps folk science." As an example, he mentions intercessory prayer, and how many attribute their convalescence to it. He claims that the following experiment refutes this. 1802 patients were having coronary bypass surgery and two thirds of them were being prayed for by some churches. Half of those being prayed for were told so, and the other half were told that they might be prayed for. In the end, there was no significant difference in recovery. Prayer had no effect: "case closed," pronounces the Sherminator: the god of the christians is impotent.

That's it? Hold on a second, Mr. Shermer. Let's lay it out. The experiment is set up thus: if there is a statistical increase in the recuperation of prayed for patients, then intercessory prayer works. Straight up conditional. But the statistics were the same. Therefore...the statistics were the same. That's it. That's what we get. The falsity of the antecedant doesn't affect the truth of the consequent. If A, then B: not A: therefore, not A. This argument, which seemed to speak so loudly and which he thought strong enough to close the case, doesn't actually say anything. Teach your kids logic, folks. It'll serve them well in the fight.