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10 Weasel words and phrases

Thank you for joining me for blog 31, highlighting decision-making and the brain. This is my public exploration of what drives decision-making and how we can use that information to make better decisions, resulting in better outcomes.

We have now moved on from the series on brain hormones to group dynamics. Why is it that groups can produce both 'the wisdom of the crowds' as well as 'the madness of crowds'? Something clearly happens when people get together that is more complicated than an individual decision.

Over the coming weeks we will take individual elements of group dynamics and try and build up a picture. Some of the topics that come to mind are i) incentives, ii) when do crowds seem to make good decisions on average and iii) the problems with poorly formed groups.


Debates within groups are not always won by the dry facts. Often, the way people present their arguments is an important part of convincing others to back an idea. 'Weasel words' are words and phrases that sound logical but are littered with vague, ambiguous or outright wrong conclusions. We see all too frequently that shaky logic is confidently employed to get people out of a weak argument and, our dearest politicians use these frequently.

Here is a compilation of my 10 favourite weasel ways that people try and mislead you with. I hope this sharpens your wits for dealing with evasive people!

1) False dilemma

A false dilemma (or false choice/dichotomy) is when someone tries to boil down a very complicated topic into two possible outcomes. A very famous example of this is George W. Bush's quote 'Either you are with us, or you are with the terrorists'. This of course eliminates the idea that you are with neither, which is a very possible position. Often, opposing views are reconciled with some sort of middle position, but false dilemmas do not open this possibility for discussion.

2) Absence of evidence = evidence of absence

It would not surprise me if vaping causes long-term harm we are unaware of today. If you were to enquire if there is any evidence of harm being caused by vaping, you would likely not find much. That is the absence of evidence. However, that logic can erroneously be extended. Let's say someone took this and then stated 'we should not have a problem with anyone vaping, as there is no evidence of harm' that does not follow. It is suggesting that just because we do not have any evidence of harm that there is none. It is similar when politicians say 'there is no evidence that Brexit has impacted the UK'.

This weasel tactic, discounts the possibilities like i) something has not or cannot be proven, ii) it is too early to say or iii) that is has been proven but they have not found the evidence.

3) Straw man

Straw man arguments often arise in public debates such as a debate on clean energy

  • A: Should we encourage clean energy?

  • B: No, the technology is not ready yet and it will result in rolling blackouts

What A is asking is twisted by B. B is answering the question 'should we only have green energy', which is not the question asked. This is an absolute favorite by politicians who have an agenda and stifle the other side of the debate.

4) Slippery slope

I once saw a debate about lowering the age of voting from 18 to 16 for a particular election. The British Youth Council was proposing the motion that it should be lowered and a group of journalists were arguing the opposite. The side opposing the motion used a slippery slope argument - if you lower the age from 18 to 16, then soon you will be asking for it to go even lower and before we know it babies will be voting. Slippery slope arguments are very common. They are often used against any loosening of barriers and they have been successfully used to fend off those who are in favour of euthanasia (if you allow terminally ill people access to euthanasia, soon it will be more widely available).

The fallacy is that a move from A --> B (a sensible move) will inevitably lead from B --> C (an unacceptable move).

5) Obviously, never, always.....

It is obviously not obvious in most cases! These words are used to strengthen an argument e.g. our company is obviously the best known in its field. However, often they are flat wrong and are trying to paper over the cracks of a weak argument. Populists win over people with the idea that there is no alternative or it cannot go wrong and these words (obviously, never, always etc) are too willingly accepted by audiences that should sense-check the claims.

6) Avoid the claim, rubbish the source

  • A: Should we travelling on fewer flights to decrease our carbon footprint?

  • B: How can you talk about carbon footprint whilst drinking from a disposable plastic cup?

This is bread and butter for evasive people. Rather than answering the question they have deflected the question by trying to bring down the questioner. This is called an ad hominem attack which attacks the person rather than addressing their question or argument.

7) Appeal to authority

A book argues that global warming is not actually happening, and cites the research of one environmental scientist who has been studying climate change for several years. This is a classic appeal to authority. Often the person cited is not even an expert in that field, for example, Michael Jordan endorsing a meditation app. By drawing upon recommendations we might be committing the opposite of 'Avoid the claim, rubbish the source' as we are ignoring the arguments and letting the authority of the claimant be the deciding factor.

8) Sunk cost fallacy

This is a very well trodden path and is used to justify all sorts of things. A good example is a team that overspent on a defender. He is not playing well but since the team spent all that money, he has to start every game. Instead of doing what is best for the team and benching him, the past costs are considered and he starts every game. We see this all the time, justifying continuing wars by referencing those that have already died, staying in a toxic relationship because you have already been together 6 months or continuing a clearly spiralling out of control rail project.

9) Association

Guilt by association fallacy occurs when someone discredits an opponent because of their association to a demonized group of people or to a bad person, in order to discredit his or her argument.

'How can you listen to someone who supports West Ham'.

The idea is that the person is “guilty” by simply being similar to this “bad” group and, therefore, should not be listened to about anything. This is clearly shaky ground as you cannot read-across that far from someone's associate.

10) Appeal to fear

'There was a solitary case of a fox mauling a child in her garden. Parents used the excuse that their children might be attacked by wild animals and decided to keep them indoors.'

An appeal to fear is either intentionally or unintentionally overblowing the risks of a situation by presenting a very unlikely worst case scenario as a reason not to do a very sensible thing.

This is often used to suppress dialogue about a nuanced subject. It is unpopular to ever expose people to risks, but lots of the argument is missed e.g. what about the risks of not allowing children outside and the impact it might have to a child's mental and physical health.

So what?

How is this all relevant to decision-making? Here are three take-aways I want to leave you with before we pick it up next week:

1) We can sometimes be convinced by confidently said/written but incorrect arguments

2) Understanding weasel words i.e. words that aim to mislead you is a good way to defend your process to get to the best decision

3) We should try and notice when we try and bulldoze others with incorrect arguments - we might 'win' the debate but could end up making a bad decision.

Thank you for joining. Next week - 'the wisdom of the crowds'.

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