Arguments are, of course, made out of language, and language is always ambiguous to some extent. If you apply the embodied meaning understanding of the meaning of language, there can never be any precise equivalence between the meaning of a word, sentence or other symbol for any two people. Each understands that meaning in relation to their own body. We do manage to communicate, but only on a more-or-less basis. If your language means something similar enough to you and to your audience, you will communicate to an extent. The same problem applies between you and your past or future self. The words you wrote in your diary ten years ago may not mean the same now.
However, issues of ambiguity are more striking in some cases than others, and where they arise more strongly in argument they are more likely to create misunderstandings and conflicts. There are two types of problematic ambiguity: ambiguity proper, which is multiple meanings for the same word or term, and vagueness, which is the lack of clear boundaries on the application of a term.
Very often, but not always, ambiguities and vagueness are just resolved by contextual judgement. For example, if I say “I’m going to the bank” and I’m carrying a chequebook, you don’t think I’m going to sit by the side of a river; and if I’m carrying a picnic basket, you don’t tend to think I’m going to have a relaxed picnic inside my local branch of HBOS. Vagueness also often does not matter: if I tell you I’m going for “a short walk”, you don’t need to know exactly how many metres I will be walking – and indeed, nor do I.
Ambiguity that affects the justification of an argument is known as equivocation. If you use the same term in a reason and a conclusion, but don’t realise that they have an importantly different meaning in each case, the justification of your conclusion is likely to be seriously undermined. Abstract words are most prone to this: for example, life, civilised, natural, beautiful, meaning, good, art, and (oddly enough) logical. Equivocal arguments often have a baggy abstract term in the middle of them that is in need of a bit of clarification, and if it’s not clarified needless disputes can ensue. Here’s an example of a dispute between Ken and Thelma:
Ken: Wind turbines are a natural way of generating energy without burning fossil fuel, so the government should be investing in them much faster.
Thelma: Natural! You’ve got to be joking! They’re the most artificial monstrosities you ever saw! A blot on the landscape!
Here Ken is using the idea of the “naturalness” of wind turbines as the basis of his argument for them, but “natural” obviously means something quite different to Thelma. They will not be able to make progress in resolving their disagreement until they have resolved what they mean by this deeply ambiguous word. They can do this by defining what each means by the term. Let’s imagine that the conversation continues in a helpful direction.
Ken: So what do you mean by “natural”, there, Josh? Is it to do with what wind turbines look like?
Thelma: Of course! It can’t be natural if it’s a big noisy metal contraption sticking up on a green hill, can it?
Ken: So “natural” means not noisy and metal? What does it mean more positively?
Thelma: In harmony with the landscape. Trees and pastures are natural, but wind turbines aren’t.
Ken: What about buildings? Are they natural?
Thelma: Most of them aren’t, but the more traditional buildings like stone barns are more natural-looking than modern buildings.
Ken: So, by “natural” you mean that it has an appearance that you feel blends harmoniously with the landscape?
Thelma: That’s right.
Ken: Well, that’s not what I meant when I said that wind turbines are a natural way of generating energy. I meant that they are sustainable and don’t cause pollution. They cause much less disruption to the eco-system as a whole when you compare them to a coal-fired power station, for example.
Whether or not Ken and Thelma can now resolve their disagreement about wind turbines, at least now they have clarified what they are arguing about.
1. Jake (looking at object pictured on right in an art gallery): How can that be art? This guy has just bought a urinal and stuck it in an art gallery!
Sandip: That’s precisely it. He’s stuck it in an art gallery. That makes it art.
2. Mother: I thought you were going to go to bed early tonight! It’s 11.30 already!
Teenaged son: But I went to bed at 12.30 last night.
3. Unionist: The management’s pay offer is only a 0.8% increase on last year’s pay, when the inflation rate is 2.3%. Some other workers in the same group are getting 2.7% rises. That makes the offer both unfair and unreasonable.
Manager: The pay offer is in line with the going market rate in the industry. That makes it perfectly fair. It is all that the company can afford without threatening its competitiveness. It would not be reasonable to expect the company to go out of business to meet an excessive pay settlement.
4. Camilla: The Quakers are not really Christians. They don’t believe in the Trinity, or that the Bible is the Word of God.
Billy: But they have an idea of God, and they come from the Christian tradition. They rely on personal experience of God rather than on the Bible or doctrines, that’s all.
5. Rosie: Your directions were rubbish! You said to go straight ahead by the Dog and Duck Inn, but there isn’t any road straight ahead at the Dog and Duck Inn, just left and right. I didn’t know which way to go! I was wandering around for ages!
Lee: The directions were perfectly clear. You just have to interpret them with common sense, that’s all! There’s a staggered junction by the Dog and Duck Inn, which means you go left and then right, but that’s practically the same as straight ahead. It should have been obvious!