prior probability

The hyper-productive Tyler Cowen recently formulated his “first law” of logical argumentation as follows: “There is something wrong with everything (by which I mean there are few decisive or knockdown … arguments, and furthermore until you have found the major flaws in an argument, you do not understand it).” Although we agree with the spirit of this statement, it suffers a serious flaw. The problem is that Cowen’s First Law is self-refuting, for if “there is something wrong with everything,” then there must also be something wrong with the argument there is something wrong with everything. For his part, Kevin Drum has fixed this fatal flaw by restating Cowen’s First Law as follows: “For any any problem complex enough to be interesting, there is evidence pointing in multiple directions. You will never find a case where literally every research result supports either liberal or conservative orthodoxy.” By the way, Drum’s restatement of Cowen’s First Law helps explain why the study of law (especially the compulsive study of appellate cases in law school) is not a science …