Genetic red herrings

17 11 2013

Screen shot 2013-03-07 at 4.14.45 PMI am way behind writing up our journal clubs, so here goes, starting with one from (ahem) mid July! Maria and Mike organized several ‘logical thinking’ discussions, and this was their last on red herrings (arguments based on irrelevancies), focusing on a sub-type called ‘genetic fallacies’. The term ‘genetic fallacy’ may be confusing to biologists, but it’s based on the root of the word – genesis. Genetic fallacies appeal to the origins or source of an idea, in a bid either to support or refute it, doing so without considering its actual merits or content. Nigel Warburton’s A-Z book illustrates what’s wrong with this by pointing out that just because chickens come from eggs does not make them good in meringues …(bleuh!)… but some actual examples of genetic fallacies probably make it clearer. One is “appealing to authority” (where the authority is mischosen), or to some well known saying; another is “getting personal”; and a fourth is “poisoning the well”.

Appealing to authority, when done fallaciously, means claiming something is true or right because a questionable authority (e.g. a celebrity) says or does it. It is the opposite of playing the Hitler card. Of course some authorities are well worth heeding, but doing so uncritically is just kow-towing (for example, claiming that something about animal welfare is right just because it’s in David Fraser’s book: I’ve had that thrown at me more than once!). “Truth by adage” involves relying on a familiar saying (e.g. “you can’t teach an old dog new tricks”) as an alternative to thinking — somewhat like the claim undergraduates often use in their essays: “It has long been known that…” (followed by some alleged truth about animals). Getting personal involves an ad hominem attack on someone’s character, rather than attacking the content of their argument. This might involve accusing them of being biased (e.g. having some vested interest), or ignorant, or hypocritical. Pointing out that someone does something themselves that they are arguing against (so implying that they are a hypocrite) is called “tu quoque” (“you also”). Like all the ad hominem fallacies, it can be a devastatingly effective rhetorical device, but it’s actually irrelevant if it sidesteps the content of the argument being disputed. Poisoning the well is similar but less personal; it seeks to discredit a group the arguer is or could be seen to be from (e.g. “Typical of a woman to say that”, “You sound like an animal rights nutso” or “No-one your age could understand”).

Confusingly, the terms “tu quoque” and “ad hominem” can also refer to legitimate moves in an argument, and this is how they were covered in Nigel’s book (which is broader in scope than the Fallacy Files). When used in this acceptable sense, they mean pointing out inconsistencies in someone’s argument (for example, you could use such a move against someone who wants to argue that killing people is wrong but capital punishment is OK); here, they are varieties of the “companions in guilt” move.