Five sayings we should stop saying

1 There's no smoke without fire.

This suggests that there is no such thing as a completely unfounded rumour or accusation. While most people would reject that suggestion if put in those terms, this well-known and frequently used saying still has the power to persuade. It shouldn't. Too often, when an accusation is made, we assume for no good reason that "there must be something in it". This readiness to believe something negative without evidence is probably an over-reaction to not wanting to be naive.

2 If it ain't broke, don't fix it.

Trivially true about machinery, perhaps, but few aspects of human life are simple enough to be described as either broken or not broken. Most may not be perfect but are probably not in need of a complete overhaul either; they need improvement. The "If it ain't broke" approach is just an excuse for apathy. We don't need to think in terms of "fixing" things, but we can aim to make them better. Conservatives love this saying because it has homespun charm, unlike its more honest translation: "Let's not change anything unless we really have to."

3 A leopard can't change its spots.

Or to put it another way, "Once a criminal (adulterer, liar, etc) , always a criminal (adulterer, liar, etc)". But why exclude the possibility of reform or rehabilitation? An equally valid saying which expresses the opposite view might be "a snake sheds its skin", implying that radical change is part of normal development. Unfortunately, the ultra-conservative and pessimistic saying is the one which actually entered the language.

4 Old enough to do the crime, old enough to do the time.

People have a tendency to believe without question anything that rhymes. This no doubt has its roots in childhood and should really play no role in the adult psyche, but it's evidently hard to shake off. There are many examples, but the one about doing a crime and doing time is a favourite among politicians wishing to sound strong on law and order. The rhyme functions are a kind of surrogate logic and seduces us into thinking an argument has been clinched. In reality, it's just a bald assertion that if children commit crimes we should lock them up - although it doesn't sound so good put in those terms.

5 An Englishman's home is his castle.

More often than not, this is trotted out as an excuse to shoot intruders. Harking back to an era when law enforcement was a private affair, it implies that the right to defend your own property is sacrosanct and the state should basically butt out. But times have changed. While your home should certainly be a haven of safety and security, calling it a castle does not give you licence to pour boiling oil on would-be trespassers.

Follow @ELTAuthor

Five bogus arguments you hear every day

1 Thin end of the wedge

People often argue against a particular measure on the grounds that a more extreme version of that measure would be unacceptable. For example, they say it’s unacceptable for patients to pay for NHS sight tests because it may lead to charges for GP appointments. This is false reasoning. Alarm bells should ring when people ask “Where do you draw the line?”.  Deciding where to draw the line is part of everyday life and discussion; there is no reason to adopt an extreme position simply because more moderate positions involve line-drawing. This is particularly true for difficult and complex issues like embryo research, where the whole debate is about where to draw the line and 'thin end of the wedge' arguments are effectively a failure to engage.

2  False dichotomy

Complex issues rarely form neat choices, but people often try to persuade you that they do. Here, the phrase which should set off alarm bells is “If we do nothing …”. More often than not, doing nothing is not a choice favoured by anyone in the debate, but is introduced purely to serve as a false dichotomy. For example: “The police need greater surveillance powers to tackle drugs crime. If we do nothing, the war against drugs will be lost.” This deliberately elides the possibility of other effective measures. Or the classic example: “You’re either with us or against us.”

3 Misuse of analogy

Illustrating a point with an analogy is legitimate and often helpful, but it can be taken too far. So while it’s fine to liken a well-run company to a well-oiled engine, it isn’t necessarily fine to say that, like an engine, the oil needs changing regularly. Analogies are only for decoration, they have no logical force. You can’t deduce anything meaningful about the target of the analogy (how to run a company) by looking purely at the source of the analogy (how to maintain an engine).

4 Misuse of metaphor

This is similar to misuse of analogy but more subtle because metaphor is like an analogy with the scaffolding removed (to slightly misquote James Geary, who has written an excellent book on metaphor: I Is An Other). The same point applies, which is that you cannot prove anything about the target by drawing inferences about the source. Saying there has been a ‘flood of immigration’ is a metaphorical way of describing an influx of migrants. It is not a neutral metaphor – it strongly implies disapproval, because floods are invariably bad news. It doesn’t tell us anything factual about whether the influx of migrants has had a negative effect; it simply reveals the speaker’s attitude. If the speaker goes on to say that it’s time to ‘stem the flood’, the same caveat applies. Yes, we always want to stem real floods because they are always damaging but no, you can’t transfer that logic to a different scenario just through choice of metaphor. You need to argue the case for reducing immigration on its own terms.

5 Caricaturing

This one is a staple of political debate and can be entertaining and effective, but from a rational perspective, it’s bogus. Usually, it involves deliberately side-stepping a specific point and responding instead with an exaggerated caricature of your opponent's opinions. So if speaker A argues that prisoners should be allowed to vote in general elections, speaker B may decide not to argue the pros of cons of the specific proposal but instead to mock a series of exaggeratedly liberal views on prison reform in general: that prisoners should have holidays in Disneyland, hot tubs in their cells, gourmet meals, and so on. This is a particularly insidious trick because it can make the person who sticks to the point appear po-faced.

Follow @ELTAuthor