"Sorry ..." "Sorry." "Whoops, sorry." "Sorry..." Okay, so that's the script (so to speak) - but what about the setting?

Well, actually, that doesn't matter too much. You see it's not a specific incident I'm describing.

The setting could be any stretch of pavement more or less congested with people variously doing their thing: some with children to marshal and/or buggies to steer, others standing bunched in private chat, as well as shop displays, bus shelters, ice-cream signs (at least, that's what I think they are), scaffolding, rubbish, among other possible obstacles or hazards, when:

"Sorry" - here comes me. That's right, the little blind fella.

"Sorry" - my white stick tapping from side to side in front of me.

"Whoops, sorry" - cautiously negotiating my way through.

"Sorry ..."

Got the picture?

But wait! Isn't there still something missing? Who's apologising to whom? Me to everyone I happen to touch with my stick or brush against or bump into? Or them to me?

Mostly, the contact I or my white stick make with my fellow pedestrians is only slight and the ensuing apologies are, you might say, droplets of social "oil" to ease our ways - both mine and theirs - through the throng. We'd all soon be emotional wrecks if every "sorry" came from the bottom of our hearts.

So an exchange of apologies generally sees us amicably on our ways. Which just about answers my question above.

But I'm totally blind. So I need to call on the services of that little five-letter word considerably more than most people would.

And, to be honest, it can get rather tiresome when, as it sometimes feels, practically every step brings some bump or blockage that I'd better get my apology in quick for - just in case. And I do occasionally give up in situations like this.

But I was taught well when I received my mobility training all those years ago; taught that, because I can't immediately assess the detail of my predicament, it's best to defuse any possible "difficulty" before it can arise.

Indeed, the "sorries" I've uttered to detect a moment of tension are often followed by the sudden realisation that I'm blind and finally a reciprocal apology.

It does work. To such an extent did my mobility trainer believe in this sort of approach, however, that one of his little sayings was "If it's soft, apologise to it." There have been shopping bags, rolls of carpet and who knows what else I've apologised to in my time - just in case.

Not that I can always get my apology in first. I can sometimes be left standing in amazement at some ferocious response to what I'd thought of as only an ordinary sort of bump.

On the other hand, there are also those who appear to believe that blind people deserve a much higher order of apology simply because we are blind. So I have to reassure them that it was just an innocuous little incident at worst; no harm done and nobody's fault, really - until I'm overdoing it, too.

I may even be totally in the dark as to what is supposed to have happened. But above all I do recognise these people are essentially well-meaning.

Most embarrassing of all, however, are those (mercifully) few times when damage is actually done - but not to me.

I may have caused someone to fall, for example. Or, to put it another way, when they wouldn't have fallen but for the presence of me and my white stick.

Because I can never be sure how much at fault I might have been. Did I turn too sharply? Was I paying sufficient attention? Could I have anticipated they'd stop just like that? Was I going too fast?

Nevertheless, that's when I do say "SORRY" from the bottom of my heart!