Glossary: Minimal risk of a remote possibility

I TRY NOT to get pedantic too often in these columns. This is partly because I'm terrified of being proved wrong (of which more later), but it's also because my attitude to language is more that of a virologist than a hygienist1 , that of someone intrigued by new mutations, irrespective of how poisonous they might be. Sometimes, though, a usage will get under the skin and start to itch; and the rather wayward use of 'minimal' is a current case in point.

It's been a very good week for 'minimal'. Both the plague in India and the loss of the Estonia have provided the sort of conditions in which this particular verbal organism thrives - uncertainty, fear, the human desire for predictable security.

So we have had reassuring statements about the 'minimal possibility' of the plague bacillus arriving in Britain on an international flight. The risk is minimal, says a government spokesman (Dr Mawhinney, I think, on this occasion); all those of us who have been prodding ourselves for incipient buboes give a little sigh through our suspiciously sore throats.

Strictly speaking, though, the government spokesman is talking nonsense. If the risk was genuinely minimal it would mean that there was absolutely no risk at all. After all, that's what minimal means - 'the least possible'. So the minimal risk is zero, no chance whatever of plague2 arriving in this country. Naturally, no politician would offer such a hostage to fortune - because 'strictly speaking' is often the last thing they want to do; it might backfire in the future.

Instead, politicians use 'minimal' as a synonym for 'negligible' or 'too remote for me to be blamed if something later goes wrong'. Had he been pressed a month ago Michael Howard might well have insisted that the risk of the IRA smuggling Semtex into a mainland jail was 'minimal' (Actually, I think he might have risked an 'impossible' in those circumstances, but you get the general point).

There is another confusion involved here - that between probability and possibility, two entirely different concepts that are often confused, a confusion which leads to an associated solecism - the 'remote possibility'.

'Remote' is useful to politicians, too, because its spatial connotations, of something far distant from the centre, provide a geographical equivalent to the false exactitude of 'minimal'. Don't worry, says 'remote', the danger is miles away. The important thing is that it doesn't ever require its user to say how many miles exactly.

But a possibility cannot be quantified in that way. It either is a possibility or it isn't and proximity hasn't got anything to do with it. It's possible that every roll-on roll-off ferry3 that leaves port in the next week will sink due to design flaws - but the probability of that happening is vanishingly small (not minimal, but very close). It isn't possible that every roll-on roll-off ferry that leaves port in the next week will be sucked into the air by Venusian spacecraft, so calculations of probability don't even enter into it.

Whatever happens to the ferries, we are in deep water here. Bertrand Russell once announced to his students that 'probability is the most important concept in modern science, especially as nobody has the slightest notion of what it means'. The concepts and calculation of probability are at the heart of quantum physics - and if you trace the history of the word in the Oxford English Dictionary you find that it disappears into a thicket of algebraic figures soon after arriving in the 20th century.

What politicians are doing in using reassurances such as 'minimal' and 'remote' - apart from refusing to be pinned down to hard figures - is blurring the distinction between risk assessment (which is a proper field for mathematical analysis) and risk perception, which is an altogether more illogical field.

Risk assessment could tell us, without fudging, that we have a greater chance of being injured in a road traffic accident than being drowned on a ferry; risk perception is what allows us to spend the entire drive to Dover worrying about the locking pins on the bow doors rather than the maniac in the Cavalier behind us.

Politicians, for all sorts of reasons, operate in the realm of perception, an area where emotional calibrations4 are more important than hard figures. This may even bring us back to quantum mechanics. What you are looking at when a spokesman hedges his bets with 'minimal risks' and 'remote possibility' is the political application of Heisenberg's Uncertainty Principle: if you can tell what a politician's position is, you won't know how fast he's shifting in the other direction, and if you can tell how fast he's shifting, he'll make sure you can't identify his original position.

1 From the Greek hugienos, healthful.

2 From the Latin plaga, a stroke or wound, an infection.

3 From the Old Norse ferja, ferry. A ferjukarl is a ferryman.

4 Possibly from the Arabic kalib, a mould. The Greek kalapous means a shoemaker's last.