Hundreds of thousands of children travel on the London Underground. When they do, they see hundreds of posters and notices. Many of the children I see, try to read these posters and notices. Many of the notices and posters do not obey the so-called 'rules' that have to be taught in school, many of them show varieties of written English that reveal interesting and inventive forms of English.
Today, I was thinking about 'commands'. In real life, we have a range of means of commanding and requesting and inviting people to do things. This is a 'social' way of viewing language according to meaning and function. We might add in there, the factor of 'effect' and whether this or that form of language does or does not tend to produce or not produce its intended effect. The kind of grammar that children in primary schools have to learn is not very interested in any of this. It starts out from being interested in meaning and then categorizes language according to its structures. It is not interested in social function (which I would argue is its true meaning) nor its effect.
So, though we use the word 'command' in every day life to mean any structure of language which commands or demands or orders you to do something, primary school grammar takes that word 'command' and uses it for one very specific structure. Really, it's not 'command' but 'what we say is a "command"'. And 'what we say is a "command"' is the 'imperative form of the verb. We all know what this is, without necessarily knowing its name. You can hear two year olds bossing their toys around using it: 'Sit down!', 'Get up!'. In English - ignore other languages for the moment - the form of the verb used for this 'imperative' is nearly always the same one as the name of the verb, which we know with the 'to-' phrase: 'to sit down', 'to get up'. You can try it. Ask yourself, what is the imperative of the verb 'to eat'? It's 'Eat!'. What's the imperative of the verb 'to grow'? 'Grow!' Then you can have some fun thinking up some verbs where it would be ludicrous to have an imperative, though theoretically in some weird land inhabited by poets and novelists they could exist, like, say, 'to internalise' 'Internalise!' Then again, some verbs are what are called 'defective' because they can only be used in some structures and not in others. So there is no 'to must' or 'to would' and no imperative 'Must!' or 'Would!' though someone like Douglas Adams could have found a way to invent one, I'm sure. And hurrah for that.
Back with the social functioning of commands: in the London Underground there is a sign which Transport for London put up at the beginning of the escalator. This is what it says:
on the right
of the edges
(Note first that there are no full stops or exclamation marks here. If you don't note it, rest assured that some children will. This tells us that when we say to children, sentences have full stops, we're not telling the truth.)
Next, note that four out of these 6 commands (every day use of that word) use the imperative: 'stand', 'hold', 'keep clear', 'take...care'. One of these imperatives has the word 'please' with it. (Never ask 2 grammarians what 'please' is in grammar. They will debate it for hours and in the end,you'll think it's either better to die or just say it's...er...'please'.) However, in terms of social function, 'please' is incredibly important. It alters the whole tone of what's going on. In terms of those who can only see the imperative, it doesn't make a blind bit of difference.
Now, we come to 'Dogs must be carried'. Terry Eagleton's gag in relation to that one, of course, is to ask, 'Does this mean that when I travel on the escalator, I must have a dog?' His point was that we only know what it really means from the context. Yes, it's a command but not of the imperative kind. It tells us that if we have a dog we must carry it. Or two dogs. Or three dogs. They've all got to be carried (!) It is a command of equal weight as the others. But not with an imperative.
And now 'No smoking'. Again, a command but not an imperative command. Again, very interesting. The phrase 'No + an -ing word' is one of the ways people who write notices command us. It has its own mini-grammar. People interested in this sort of thing happily go off into speculating about 'what's left out' of phrases like this. I'm particularly not interested in that, because I am a firm believer in only looking at what's there, and not what's not there. 'No smoking' is using a standard command form in English, end of. It doesn't say, 'There will be no smoking' or indeed any other phrase which includes 'no smoking'. We just get it from those two words. It is a command.
So, children looking at that notice will, as like or not, 'get' what's being asked of them or their parents. They are demands and commands and orders each with a slightly different tone. You could indeed do a check on 'effect' by standing next to an escalator all day and seeing if people are standing on the right, holding the handrail, keeping clear of the edges, taking extra care of their children, carrying their dogs and not smoking. Whether there is a one-to-one cause and effect relationship between people reading the sign and obeying the instructions would be a fruitful area of exploration. After all, some of these signs appear elsewhere, the reason for not smoking might not be because this particular sign was read!
Anyway, the long and the short of it is that there is tons more fun (when you're 6,7,8,9,10 or 11 years old) looking at a real notice like this, and thinking about 'please' and whether to carry your dog or not, then sitting in a classroom filling in a sheet that 'demands' that you spot the special 'command' required of the test, and reject the others - in other words where the examiner has stripped this piece of education of its social function and meaning.