Technical manuals are clear, direct and precise, right? The content is factual. There’s going to be none of the pussy footing around and ambiguity that we’d associate with the ‘polite’ stuff that folks (like me) usually write about, right?
There’s a great research paper here on ‘simple English’ that illustrates just how wrong these assumptions are.
Operating manuals contain a large number modals verbs
You must do an inspection of all the tubes
The handle should be folded inside the stabilizer trim
‘Should’ differs from ‘must’ in terms of the expectation of compliance – how confident we feel that it’s going to happen.
You must inspect it (and I think you will because I have told you to)
You should inspect it (It’s the right thing to do but perhaps you won’t)
And then there are some more ‘fuzzy’ modals like ‘may’ and ‘can’.
Use of long range cruise may be appropriate
Mercury vapors can be toxic
Something interesting about ‘may’: if I say you may do something, it also implies you may not. It suggests that I am not fully committed to the instruction, so if it turns out that it wasn’t appropriate to use long range cruise, I can’t be held responsible. And there’s a similar lack of commitment if I say ‘can’. In some way, I’m less responsible for the outcome.
The language of technical manuals aspires to be plain, straightforward English, so we might expect that all manuals would be similar in their use of these modals – irrespective of their audience.
They’re not. The study shows that operations manuals written for high status pilots, have fewer uses of ‘must’ and many more uses of ‘should’, ‘may’ and ‘can’. In repair manuals written for lower status technicians, there are more uses of ‘must’.
Like the authors of this study, I reckon that it’s about status. I can’t see another sensible explanation for the disparity. We might like to imagine that technical language is socially neutral and free of fuzziness, but in practice, that’s not the case. Writers of manuals attend to politeness issues – like the rest of the human race – and if they are writing in Anglo-English, they will attend to a social requirement to pretend like the other person has a choice.
And I’m not suggesting that this is good practice or bad practice. I’m just saying it exists. And I think that if these politeness issues are there, we need to address them and teach them – to everyone, including (and maybe especially) our techie students. All thoughts welcome, so please chip in if you have ideas on this.
Other postings related to this that you might be interested in: