Friday – visit Mum and Dad in Suffolk. I take the train from Liverpool Street to Colchester. The trains are now run by National Express, as in the coach company. Seems odd getting on a National Express train, but the previous owners were worse, going by the snooty and slightly pretentious name of ‘One Railways’.

Wonder if that Divine Comedy song, ‘National Express’ is thus rendered anachronistic. Taking a National Express now means getting a train too, at least in East Anglia.

I always choose the designated Quiet Zone on trains. This is one of those recent developments that hints at a whole side of 2008 UK mores, desires and lifestyles. It’s a chapter in the history of personal space in public places, and the changes in what people expect.

Firstly there’s the idea that a default train carriage is one that’s brimming with noise and cacophony. That noise is the norm, while quietness is unusual. Just as there were once areas where it would be assumed you would either smoke, or not mind people smoking next to you, whether in trains, buses, cinemas and so on.

Then comes in the designated ‘Non’ area, the single non-smoking carriage, the rule that smokers on buses have to go upstairs. Then the Non-area becomes the norm, from all of trains to all of pubs.

Two Beatles images leap into my mind at this point. One is from 1968, where the mustachioed band are sitting in cinema seats, watching Yellow Submarine at its premiere. What’s most noticeable is that they are all smoking. Smoking in a cinema. The other is the lyric from ‘A Day In The Life’, where the narrator catches a bus, then says ‘found my way upstairs and had a smoke.’ Both ideas seem unthinkable now.

Well, except on a few occasions when I’ve been witness to people on buses and trains taking their chances and lighting up, and I’ve been the only other passenger. These bold offenders tend to be groups of giggling young men who assume – rightly – that I’m not likely to come over and ask them to desist. In these recent examples, the smoke in question is always spliff smoke.

Hypocrite that I am, although I’ve smoked (both types of leaf) and have indeed been loud in public, I think I do slightly resent being at the mercy of nearby strangers, when they’re indulging in the things I’m going without, when their smoke – and their noise – carries over into my space. I suppose what one really wants is private booths on all forms of public transport: little sci-fi bubbles. Different sizes, for the times one is travelling in company, and the times one is alone.

I do wonder who started the idea of the Quiet Carriage, whether there was a series of complaints, a campaign, or dedicated lobbying (perhaps by the Noise Abatement Society), or if it was a consensus decision reached by the relevant committee at the top of the company, which is usually the way change happens.

When I talk about Quiet Carriages to Mum later that day, she says that it’s always worked fine for her. In her experience, the QCs have indeed been silent to an extreme level, where things like someone rustling a newspaper are curiously amplified by comparison.

I’ve had no such luck. Every time I’ve been in a Quiet Carriage, there’s been as much noise as I’ve been used to in normal carriages. If anything, they’ve been noisier. I’m starting to think it’s a conspiracy.

On the train to Colchester: two groups of small girls being perfectly normal, but in the wrong carriage for it. They are running about, whining, crying, playing beeping handheld computer games. Their mothers are frequently telling them off, even one saying ‘this is the Quiet Carriage – shh!’. So, one wonders, why doesn’t she take them to a non-Quiet carriage? It’s not as if it’s a packed train – there are plenty of empty seats in the other carriages.

Coming back to London: again, plenty of seats in all carriages. I go for the Quiet Zone once more. A man comes in, sits directly under one of the many window signs depicting a mobile phone with a ‘Non’ slash through it, and proceeds to make a loud series of calls throughout the journey. I should add that he is drinking from a can of lager. It’s one thing to tell off someone for transgressing a rule based on consideration for one’s fellow man, it’s another when the possibility of them reacting drunkenly – and maybe violently – has been introduced to the mix.

Again, lager or no, it is not going to be me who goes over and tells him off.

Getting into a Quiet Carriage a few months ago – three other passengers there. They are ALL talking away on mobile phones. And once again, there’s plenty of seats in the Noisy Carriages. I start to wonder if there’s a kind of reverse psychology in action: an ‘I dare you’ aspect to the signs. Or if they all think they’re being perfectly quiet on their mobiles: speaking a lot lower than usual, at least according to their own Index Of Noise. It’s other people who are noisy, not them. Their idea of noise is different to mine. And so I’m forced to wonder if my idea of noise is the unacceptable thing here. That – as ever – it’s me that’s the odd one out.

In fact, on both journeys this week, when the ticket collector passes through, he doesn’t do anything about the noisy passengers himself. And on that Norwich journey with the cannabis-smoking boys, the collector passed directly through the cloud of their pungent smoke. Maybe he was their friend. I’m in no position to start playing the role of the Everyman.

What if on these occasions I’m the only one who minds? It would be wrong to expect others to fit in with my world. I have to fit in with theirs. I keep quiet, I promise not to start fights, and the world agrees not to kill me. That’s the whole Dickon Edwards deal.

So the etiquette of the Quiet Zone is based not on the wishes of the conductor, but on the wishes of the least tolerant passenger: one who is also capable of challenging an offender. And I would never like to be thought of as the least tolerant / most telling-off-capable person in the room.

I envisage the challenged person retorting ‘But I’m not being noisy! This isn’t noisy! This is consideration!’

And then they ask everyone else in the carriage:

‘Hey! Do YOU think I’m being noisy? Do YOU? What about you?’

And whether through sincere agreement, or just English embarrassment, they all take the side of the noisy phone user rather than mine. After all, I’m the weird one. I hardly use phones at all, in fact. I’m a creature of email.

Then – as my nightmare spirals – a conductor comes in, asks about the commotion, and I am pointed to. ‘That’s the troublemaker!’ Then all the passengers rise as one, form a mob, grab me, lift me above their heads, carry me to the door, and hurl me from the moving train, cheering.

It is me that is the strange one. So it is me that must never speak up.

So I sit and simmer and sigh while Mr Lager brays away on his i-Git Phone beneath the No Mobiles sign, hoping someone else in the carriage will play the part of the Outraged Common Sense Everyman for me. Because I cannot.

(I’m also secretly hoping there will be a bit of a conflict if he is challenged. Maybe even a fight. In which case I’ll get a ringside seat…)

But no one challenges him, and he natters away till the train pulls in at Liverpool Street. In fact, he continues chattering loudly on the platform – he seems to be in more of a monologue than a conversation. I find myself lengthening my stride to the point of running, desperate to get away from him. As I scramble to put my ticket into the barrier and make for the Tube, I can still hear him, behind me, walking and talking. I wonder if he ever stopped?

I suppose all I am saying is Give Intolerance A Chance.

It’s an update of the old joke – ‘I can’t stand intolerant people… Except when I want there to be one.’