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Tuesday, September 28, 2004
Three more fallacies

The Adam Smith Institute has now made Madsen Pirie's 1985 The Book of the Fallacy available free online, and it's a good read. Rather better than those tendentious, Latin-dominated logical fallacies web sites, the book has lots of humourous examples as well as charmingly cynical advice on how to use the fallacies yourself when necessary.

Whether it is comprehensive or not, I cannot say, not having read it all yet. But if I haven't missed them, I would myself highlight three big fallacies that do not appear in the book, even though they are fairly common in debates. I suspect the reason they aren't there has to do with the fact that in two cases the fallacies are simply quite modern reactions against other, more established fallacies. So here goes with my ideas on three more:

1. The first is the idea that every time someone makes a personal attack on someone else, he is guilty of the ad hominem fallacy (believing that by attacking a person he has refuted his argument). This usually comes up when someone writes a passionate polemic, mixing in reasoned argument with humourous or not so nice jabs at his opponents, and is then accused of committing a logical fallacy, as if a perfectly sound argument becomes illogical if you mix in a few derogatory sentences.

It is true that you fail to recognise that an argument remains untouched after attacking only the person who makes it, then the fallacy can fairly be applied to you. But merely attacking someone is not in itself a logical fallacy. If someone says Tony Blair or George Bush is a warmonger, it doesn't provide an argument against the Iraq War, but nor has the person who says it committed a logical fallacy.

As well as in uninformed internet debates, I've seen this fallacy committed in a leading philosophy magazine. The author was demonstrating that Richard Dawkins' arguments against religion (with which I disagree, I might add) are flawed, and one of the examples he gave was that Dawkins peppered his criticisms with ad hominem attacks on religious believers. Argumentum ad hominem!, the author cried. But there was no suggestion in the examples given that Dawkins' biting and often witty remarks were parts of his argument against religion. In logical terms, they may have been redundant, in the sense that they did not advance his argument. But they did not hinder it either, and it is to fail to understand the ad hominem fallacy to think personal attacks always do.

2. Second would be the idea that arguing from analogy or by comparison is always flawed. Just as an ad hominem attack is not illogical unless it is actually intended as an argument against that person's beliefs, an analogy is not illogical unless there is something actually wrong with the comparison made.

Take a commonly heard analogy: that gradual infringements on liberty are hugely dangerous because, like a frog who sits in gradually heating water until he boils to death, people don't pay attention to the very slow worsening of their circumstances until it's too late. It isn't a counter-argument to find just any way in which people and frogs, or tyranny and boiling water, are different from one another. Nor is it enough to say "But people aren't frogs!". A counter-argument needs to explain what relevant characteristics make the frog in water comparison invalid - such as the argument that people, unlike frogs, have a particular cut-off point and will not accept any transgressions beyond that, while frogs have no particular limit as long as you heat the water slowly enough.

We've all seen lines like "It's politics, not baseball!" or "You cannot compare Native Americans to fish!". But of course you can make baseball analogies when discussing politics, and you can explain some way or other in which Red Indians are comparable to fish. When Juliet says that, because a rose by any other name would still be a rose, Romeo's family name does not change what he is, she hasn't committed a logical fallacy. But a person who says "You can't compare people to flowers!" has.

3. Third would be the idea that naming an argument is the same thing as refuting it. When people argue, they often resort to vituperation and insults. Most people realise that it doesn't advance the case at all if these insults attack the person rather than the argument. But fewer seem to understand that merely saying that an argument is 'mean-spirited' or whatever does not provide a refutation.

Again and again in debate, one hears people describe contrary arguments as 'sexist', 'homophobic', 'unpatriotic' or 'anti-American' as if that proves they can't be true. But truth is no respector of political correctness (on the left) or national greatness (on the right). It's as if in such minds ideology takes precedence over truth - that if someone provides figures showing how much better nurses women make or how much better soldiers men make, one needn't refute the claims on factual grounds, because the mere fact that they contradict one's politics is refutation enough. There's certainly plenty of anti-Americanism about (and I regret that) but it's not an argument against it merely to name it.

This fallacy has a lot to do with wishful thinking and a poor ability to separate facts and values. Nothing could be more sexist than the fact that the average woman in her thirties has the upper-body strength of a male pensioner. Nothing could be more 'Islamophobic' than the almost total absence of basic civil rights and democracy across the Muslim world. If it makes people feel superior to label these facts such, then they can do so. But they shouldn't confuse that with a refutation.

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